Well, I'd like to welcome everyone to the NeuroU, the official online educational resource for AANS and the Front Row series featuring today's skull base surgery. Again, this is a unique series featuring renowned experts from around the world on a variety of topics. There is CME offered with this educational resource and participants can have access both to live events as well as the archived events retroactively for CME. And something that is new and very exciting is that participants can actually submit cases for expert discussion that can be either cases that were completed already and we know the entire story or it can be cases that we don't know the entire story and some surgeons are looking for some expert input or another perspective. Some of the logistics, we'll go over some presentations and there will be a Q&A in the chat. Please feel free to put your questions in the chat. We'll go over some of the submitted cases and some other cases that we have and discuss with the experts and then we'll do some more Q&A at the end. I'm George Zidanos. I'm joined today by my co-host, Dr. Setri, Dr. Varun Setri. And our guests really need no introduction. We have Dr. Juan Fernandez Miranda. Dr. Fernandez has been my mentor and my teacher. Most of what I know, I know because of him. He is the professor of neurosurgery and ENT as well as the surgical director of brain tumor scabies at Stanford University. He is internationally known for his surgical anatomy innovations and he's really spearheaded a lot of the more modern and cutting edge surgical nuances of endoscopic surgery and today he will be discussing some of them as they relate to pituitary surgery. We also have Dr. James Evans. Again, no introduction needed here. Dr. Evans has been the past president of the North American Scalp Society. He's a professor of neurological surgery and ENT as well as the division chief for brain tumor and SRS, the director of cranial-based and pituitary surgery as well as the director of the fellowship program at Thomas Jefferson University. He's really also a giant in the field of scalp-based surgery and minimally invasive scalp-based surgery and today he's going to give us a tour de force of the modern reconstructive techniques in pituitary surgery and beyond and talk to us a little bit about his experience. So without further ado, I will ask Dr. Fernandez to share his screen and I'm really looking forward to it. Thank you, George, for your kind introduction. I must say I'm very proud of all you are doing. Keep doing this great work and great to see you all, Jim and Paris. So George asked me to talk about cutting-edge anatomical counseling in pituitary surgery. So these are my conflict of interest. So first I want to lay down some principles that I think are important about modern pituitary surgery. The first, of course, is about the use of this privileged visualization tool we all use these days or most of us, which is the endoscope and it really makes a difference because when you use an endoscope, as you all know, you have a wide-angle view that allows you to do many more things that you cannot do with a microscope. So that is a major difference. Second principle that is important is that pituitary surgery is actually a skull-based surgery. And I think the time where surgeons were exclusively pituitary surgeons, I think those belong to the past, in my opinion, and now modern pituitary surgeons have to be, they should be, skull-based surgeons because many of these cases require skull-based expertise. And it's not about doing small, minimally invasive approaches, it's about doing a skull-based approach where we maximize the removal of bone to minimize neurovascular manipulation. In that sense, like Dr. Sekar said, there is no place for occasional skull-based surgery. Similarly, I don't think there is place for occasional pituitary surgery. And I think this is extremely important, especially in the academic environment we all practice. Another very important principle is that what we do is this actually is microsurgery, or we use microsurgery-like techniques. And that means it's not all about using a cred, it's about using gentle suction and contraction, special design dissections, micro-scissors, all these tools, just like microsurgery, so we can really remove tumors that were not possible before. Another important principle is that this is also teamwork. We are both neurosurgery and ENT working together. And this, in my opinion, makes a big difference for many aspects of the operation, both for the approach, for the harvesting of flaps, for example. But also you have a superior operability, because you can use your two hands for operating while the ENTs are driving the endoscope in a dynamic way. And I think this is superior than using holders or by doing all on your own, or with someone that is not actually an ENT expert. So I think teamwork concept is very important, and the whole, in this case, will be greater than the sum of its parts. And the final principle I want to really put out is, we need to respect the learning curve, and it's so important to undergo both laboratory and clinical fellowship training, become specialized in this field of pituitary and skull base surgery. This is not something, in my opinion, you learn in residency, but you establish some knowledge in residency, but you really need to grow through fellowship training to really become specialized. Therefore, and after this, you really can grow and become an expert in the field. So some of the key concepts I want to start sharing with you today is the concept of the dural layers in the pituitary region and the walls of the cavernous sinus. So as you all know, we have two layers, periosteal or outer layer, and meningeal or inner layer. These two layers, they bifurcate in the cavernous sinus, or laterally, in a way that the outer layer becomes the anterior wall of the cavernous sinus, you see right here, a single layer, and the medial wall, or sorry, the deeper layer becomes the medial wall of the cavernous sinus. It's a layer of dura that completely embraces the pituitary gland. And this knowledge is the key to understand why the medial wall is so important. The medial wall importance was first illustrated very well by Professor Oldfield in his tremendous studies of Cushing's disease. So in some cases, are actually invading or even growing within the wall of the cavernous sinus. And he described his technique of medial wall removal, which you see illustrated here. There were other groups like this Japanese group that they showed some cases invading the medial wall, in this case, in growth hormone adenomas, and how moving this wall improved the remission rates in their case to 85%, much better than reported in previous series. So with this in mind, we had a great interest over the last, you know, years on studying the medial wall of the cavernous sinus. And we went to the lab and as we were studying this, we found all these ligaments that many of you I'm sure have seen when you work into the cavernous sinus. We call these ligaments the paracellar ligaments. And among them, the most important is this carotidoclinal ligament, which is this superior extension of the medial wall of the cavernous sinus that actually forms the proximal dural ring, the ventral aspect of the proximal dural ring. This membrane, which is very robust in many cases, separates what we call the clinodal segment of the carotid above from the cavernous segment of the carotid below. And in other words, it separates the clinodal space above from the cavernous sinus space below. This ligament, again, is important to recognize because it is what is anchoring the medial wall. So if you want to remove this medial wall, you have to transect this ligament. You can see this ligament in a horizontal view in this picture right here in this illustration. It comes from the medial clinoid and then fans out from the medial wall of the cavernous sinus to go behind the carotid and goes towards the anteroclinal process. And again, it forms this sort of roof of the cavernous sinus. As we said, it separates the cavernous sinus from the clinodal space. You see in this illustration of both open and endonasal anatomy, you can see the CCL, the carotid carotid ligament, separates this cavernous sinus from the clinodal space above. There is another important ligament, which is the inferior parasital ligament. And it's very important because it is very constant. We see it in most patients. And this is the first ligament you're going to encounter as you open the anteroval of the cavernous sinus. You can see it in this illustration. As you come from below, it's the first one you find. And also it's a good landmark because behind, you're going to have the inferior hypovasial artery. You know, anytime I work inside the cavernous sinus, I'm always worried about avulsing the inferior hypovasial artery or any of the branches of the carotid artery. So for me, it's important to identify the artery. And then if I see it, I need to mobilize it, just coagulate it and cut it so I can really move the carotid without risking an avulsion. In this illustration, you can see in great detail all this anatomy together. You see from the middle clinic here, the CCL sits just below the middle clinic, right? And here is the outer layer of dura that is preserved. But here we've opened the outer layer. So we can see the inner layer with these ligaments, the CCL and the inferior parasital ligament. Behind the inferior parasital ligament, the inferior hypovasial artery. And behind the CCL, all the way in the back, we have the tip of the posterior clinoid and the interclinoidal ligament that runs just parallel to the CCL but posterior. These are so important to have a picture like this in your mind when you're doing surgery in the cavernous sinus. There are other ligaments that are less relevant that we try to classify, but again, not so constant. With this knowledge, we describe this sequential, stepwise technique for removal of the middle wall of the cavernous sinus when it's invaded by tumors. And basically, in these illustrations, you can see, you know, often remove this tumor, but then there is some remnant. And as I'm going to show you, this is particularly relevant for growth of monadenomas. But sometimes you can have remnant in the wall of the cavernous sinus that you cannot easily remove. And then the best way to address this is to open the anterior wall of the cavernous sinus. So separate, actually, middle from anterior first with a dissector. Then with this knife, I like to then open widely. And this widely or wide open on the cavernous sinus, of course, you get venous bleeding that you can control with some gentle packing, but allows you to see the carotid right on directly. And for me, it's very important to feel comfortable working the cavernous sinus. I need to identify the carotid artery because that's the structure I want to preserve. Of course, I'm not damaged, so I need to see it. Once I see it, I'm going to feel better. And then I have this inferior paracetal ligament. Then as we described, then once you cut it, you can really mobilize the medial wall more. You can find the inferior hypovasial artery, you can coagulate it. Then you start peeling the dura that covers the posterior clinoid. And I'm going to go all the way up to the interclonal ligament, which is my other reference. Then it can transect the carotid clonal ligament. It has, you know, fibers from superficial to deep that you need to transect. And at the end, you can remove and block this medial wall. And at the end, it looks like this. You have the posterior clinoid, naked here, and then the ICL, interclonal ligament, and the carotid all exposed. This way, you complete your resection of the medial wall of the cavernous sinus. So I'm going to show you a couple of examples here. And this was a surprise. You know, a tumor like this, who would say that this is a small tumor is embedded in the medial wall of the cavernous sinus. But I saw this case, which is not a difficult one, just to illustrate that this is a NOSP 0 or 1, depending on how you, 0 or 1, let's say that way. And then, you know, we have done this wide exposure and exposing the anterior wall of the cavernous sinus as well, so we can really see. And then this is the portion of the operation that is very standard. We just open, we're going to find our plane of separation between the pituitary gland and the pituitary tumor. This is again, growth melanoma with the classic white disappearance. And then you look at the medial wall. We see a nice medial wall here, and you see these implants. And they don't come with a dissector. So they are really attached to the medial wall of the cavernous sinus. So what I'm going to do is I'm going to open the anterior wall, separate medial from anterior with a knife, right angle knife, I can open it. You get venous bleeding. But again, this is easy to control with, you know, this hemostatic material. And then I start separating the medial wall from the anterior and from the carotid itself. I'm in the search now of the inferior ligament. And also in search or thinking about the inferior hypophysial artery. So here you have the two layers, medial wall, anterior wall. I just coagulated there, the artery and the ligament, so I can transect them. And then this is the base of the posterior clinus. So I just cut along the body of the posterior clinus, all the way to the tip. And then as I keep dissecting this medial wall from the carotid, then you can see here the tumor that is growing through the wall of the cavernous sinus. And then my upper attachment is the CCL that I'm just going to cut, as you see here, and then I can remove the medial wall and block. In this case, it's easy because there are no attachments to the carotid. Okay, this can become quite challenging when the tumor is really stuck to the carotid artery. But in this case, it's relatively simple. And what I've been doing for the last years is I'm collecting these samples and I send them to the pathologist to find out if histologically we can identify tumor invasion. And I'll share with you our important findings in this. So these are the cases I've done here at Stanford, you know, in the last 120 pituitary cases I've done. In 63, I removed the medial wall or I entered through the medial wall into the cavernous sinus. So more than 50% required cavernous sinus work. And then in all of these, I was fortunate not to have any injuries. There is an incidence of less than 5% of transient double vision from a 6 nerve palsy that in all patients recovers within weeks or up to three months. Therefore there is no permanent morbidity. And then you see the recurrent adenomas I do very often require invasion of the medial section of the medial wall of the cavernous sinus, just by definition. So I'm going to show you another example of a patient with severe Cushing's disease. And if you look at this, you can see the disease right in the medial wall or it's stuck to the carotid artery. So now I know this is going to be in the medial wall of the cavernous sinus, this patient with Cushing's disease. So it's the same thing, wide opening. And then I'm working the cell first to see if there is any tumor. And then I'm disconnecting the door along the floor of the cell, along the posterior clinoid, opening the ring to the cavernous sinus. And then now I want to see directly the carotid artery, as you see right here. And in this case, it's a little bit more difficult because it's a redo case that the medial wall is a bit more stuck to the carotid artery. But still I can find a good plane of dissection. Now I'm dissecting above the CCL into the clinoidal space. And in this case, interestingly, the CCL actually was embedded by a tumor. So I'm dissecting the CCL and I'm disconnecting it. You see the correlation between the anatomy here and the intraoperative view. And then I'm transecting all the way again to the posterior clinoid. And then this is peeling off the medial wall and the CCL. And you see the tumor, the soft tissue that is growing within the medial wall of the cavernous sinus. As we said, always I worry about the attachments on the carotid artery. So I'm going to be finding my inferior hypovasial artery so I can coagulate and transect. And something that I've been fascinated by is how these tumors actually are totally embedded in the wall of the cavernous sinus. They don't spread into the cavernous sinus, they are within the wall. And when you're able to remove this wall and block, you can remove all the tumor. You see, this is the last bit of the tumor and that is the inferior hypovasial artery. And I can finally coagulate, actually this is the inferior hypovasial artery right here. And then I can coagulate and remove this entirety. So this is not an easy operation because you are working so close to the carotid artery, you need to dissect it very carefully. So I would advise the younger audience to, you know, I think this is the way to go, but you need to become experienced, comfortable doing this, because there are some risks to doing this if you don't do it, you know, the proper way. So respect the learning curve, please. So what we found, we're preparing our paper here, these are tables for publication hopefully soon. We found that somatotrophic adenomas, they have a significant, statistically significant higher incidence of invasion of the Middle World when you compare with any other of the series. Of course, the most important relevant factor is the NOS grade, but that's well known. But being a somatotrophic adenoma is a significant higher risk of invasion of the Middle World than any other tumor type. In fact, if we looked at NOS correlation of SNOP of NOS grades with invasion of the Middle World, we find out that NOS grade, it actually is not that helpful in growth of adenomas because we see that in grade one, up to 57% in our series were invading the Middle World of cavernous sinus. And grade two, all of them were invading the Middle World of cavernous sinus. And this is very different than when you compare with the other adenoma types. We also look at our growth hormone levels immediately post-op within 24-48 hours, and we saw that our levels are below one as an average, 0.9. And this is significantly better than groups that are very experienced. And I think this translates that this technique being more aggressive makes a difference in the outcome. And our primary results here with acomegaly patients in our first consecutive 30 patients, we are seeing that the normalization of IgM1 levels at three to six months happens in 93% of all patients just with SUGIT. And the other three are in remission with medication, one of them with additional radiotherapy. So, these results are significantly better than my own series from before, and from series reported. And I think this is because of, you know, this Middle World resection and recognition that growth hormone adenomas invade the Middle World so often. Now, in addition to the knowledge of the Middle World, it becomes very important to understand also the cavernous, inside the cavernous sinus. And as we said before, Middle World, tumors in the Middle World often expand the Middle World, but they also can extend into different compartments. And you know, we published years ago about this concept of the compartments of the cavernous sinus. Professor Roton actually was the first describing these venous spaces within the cavernous sinus and categorizing them. So we based our classification on his and we modified them into a superior, into a posterior and an inferior compartment, and then a lateral one. So I'm going to quickly review the anatomy of each compartment. Superior compartment is the one that is above the horizontal cavernous carotid. And there are three things we need to identify here. One is clinoidal ICA. Second is interclinoidal ligament, as you see right here. And the third is the duraldeoclomal triangle with the prominence of the third nerve. I'm going to show you this example. This is a tumor that is a prolactinoma that is resistant with high-dose medication. And you can see the tumor here. I'm going to show you that this is growing in the superior compartment of the cavernous sinus. So again, this is that case. Medication-resistant prolactinoma. So we do a very wide exposure. The whole anterior wall of the cavernous sinus is exposed. The whole carotid is skeletonized. And I'm going to open the anterior wall of the cavernous sinus very widely. And you see, I start seeing this membrane. This membrane is middle wall. So the tumor is pushing the middle wall and invading the middle wall. And you're going to see how then it goes into the superior compartment. So first I'm doing the same operation by disconnecting the anterior wall flora of the cella along the posterior clinoid. And then this membrane is really stuck to the carotid. And then this that I'm pulling here carefully with my pituitary forceps is the CCL, the carotid-clonal ligament that is again invaded by tumor. So what I'm doing is following the tumor superior into the superior compartment. And actually this oculomotor triangle is partially invaded. So I'm removing part of that. And then you're going to see on the other side what you see is the PCA or PCOM better said. And then the third nerve, because I know the anatomy is going to be right here, more lateral. So this white thing you're seeing here is not the third nerve. That is the interclinoidal ligament. The third nerve is going to be more lateral. But this way I can see the clinoidal carotid as we said before, and this is our PCOM and the third nerve will be more lateral. So this is working in that superior compartment. Now, and this is here quickly, the post-op of this patient, you can see tumor going to that superior compartment removed. The other compartments that we care about are the inferior one. This is a very important compartment to identify. This inferior compartment is below the horizontal carotid as you see here in this illustration. And then our limit is the sixth nerve laterally. So we have all this space to work here. So if you really expose the anterior wall and you open the wall, you can access this inferior compartment. Here, the sixth nerve is at risk, but it's lateral. So you can work carefully until you get laterally into the sixth nerve. So when you look at MRIs, I like to look at a cell and see there is tumor in this view, below the horizontal carotid right here. For example, like this acromegaly patient, there is tumor in this inferior compartment. So I'm going to show you this quickly, this case. This is a very invasive acromegaly. You know, it's an Osp3B category would be. And what I want to illustrate with this case is even in this case, it's all about the middle wall. The tumor has really grown within the middle wall as in this illustration, and really extended to the cavernous end, but it still is contained within this middle wall. Now it becomes very challenging because there is a lot of tumor that is very stuck to the carotid artery. But if you are able to work your way in, you can see that it's tumor poking through the wall, but I can dissect it. This is the carotid artery. You saw the dura of the oculomotor triangle up there, as I was resecting tumor. And I'm literally peeling this tumor off all the attachments from the horizontal carotid here. And now we're going to go into the inferior compartment in this area. Those are the posterior attachments. And that's cutting along the posterior clinoid. I'm always using this Doppler ultrasound in surgery to assist with the resection. And now we are into this inferior compartment. I'm going below the carotid. I'm finding these attachments. I know the six nerve, this is the stimulator I use in surgery. The six nerve is located just lateral, so I'm protected now. But look how this tumor is really contained in this membrane. And then I'm covering the dura at the floor of the inferior compartment, and then I can just transect all this tumor not as a single piece, but the medial wall portion as a single piece. And I achieve a complete tumor resection in this patient with actually remission in a tumor that this large. You see all that was the tumor embedded in that medial wall and the carotid here is all nicely exclutinized and exposed. And this patient, again, as we said, crashed, not crashed, but got into remission two months later with a very good post day one growth hormone level. Now we have the posterior compartment. And this is one that is easily forgotten. This compartment is behind the short vertical carotid as it enters the cavernous sinus. It is on top of the durellus canal. As you see, this is the six nerve entering the cavernous sinus and durellus canal is above the six nerve in durellus canal. In this area, that is difficult to work in. First, because you need to do a very good exposure, mobilize the carotid. And second, because you are so close to the six nerve, so you also have to be very careful. So basically, it's tumor located in this area behind the carotid, just above the durellus canal right here. So I'm going to show you this example of this case. This is a non-functional adenoma, superior compartment, inferior and posterior. The three of them are partially embedded. Now, this is a young patient, and I often get asked, do I do the same type of operation for a non-functional adenoma? And we're always more aggressive with functional adenomas for obvious reasons, but I am also relatively aggressive with non-functional adenomas, especially in young patients, because some of these can recur if you don't remove them well. And if I think I can do this with low risk, I will go for a complete tumor resection, even if I have to go into the cavernous sinus. So here you see the anatomy. This is clinical carotid. This is interclinical ligament. This is the middle wall of the cavernous sinus that is embedded in this case. So then I find the carotid. And in this case, there is tumor that goes into the inferior compartment. And again, I'm thinking about the 6NRF, and that is the 6NRF right there. I use my stimulator, which mostly helps me to determine whether the 6NRF is going to be intact right after surgery or not. It doesn't really help me that much finding it. I think the anatomy is what helped me find the 6NRF, but it's an assistant that is valuable. And then we are peeling this embedded wall that is stuck to the carotid. And then we just coagulate any remains of the tumor. If they are very stuck to the carotid, I just don't try to do this too much. I just coagulate any remains of the wall or the tumor by the wall of the carotid. But this patient has, this way, young patient, a complete tumor resection with no residual. Now, lateral compartment is the one where I am most concerned about it, because I know that this is tumor that is between the carotid artery and the lateral wall. So the nerves, specifically 6NRF, are running in this area. And I tend to be a bit more conservative now. There are cases where they are either functional or the tumor is relatively soft, where you can actually do a very good job cleaning all this lateral compartment, but the risk of 6NRF palsy is the highest, in my experience, working in this compartment. So just to wrap it up, I'm going to show you this case and a couple more nuances in between the surgery. So this patient, young patient with severe Cousin's disease, previous operation, you see how large this tumor is. That's why I said, this is not pituitary, this is skull base urea. This tumor is a panclival tumor, cavernous sinus invasion, supracellular invasion, going actually here through the oculomotor triangle. It goes all the way down to the clivus and invades the pituitary apex bilaterally in the area of the foramen lacerum. And we recently described an atom with the foramen lacerum and how to expose it. And I think this is another very important nuance for these transclival approaches. We talk about this triangle where, if you follow the stereosphenidal fissure and the median nerve, you really can expose the foramen lacerum and that gives you the bottom of the carotid. So you can expose carotid from all the way down, all the way to the cavernous sinus. And also allows us to mobilize the carotid gently and then identify this very important anatomy here, landmark, which is what we call the petrosal process of the sphenid bone. This is important because the sixth nerve is just above this petrosal process. And with your dissect, you can find the slope of the bone. And when I find the slope of the bone, I know the sixth nerve is gonna be just lateral and behind the carotid artery. So this is a very effective way of finding the sixth nerve in the direllis canal, the petrosal process of the sphenid bone. And last ones, this, you know, in this MRI, for this tumor, you see this line right here. This is the oculomotor triangle. The tumor has pierced through the oculomotor triangle. This is the intercanular ligament. So it has broken through the oculomotor triangle into the interdirectional space. And this also we describe in another paper, you know, describing how these tumors actually break through the posterior part of the oculomotor triangle here. And then they're gonna displace the third nerve up and medial and not lateral based on what we found. So with this case, we'll put all this anatomy together and all these different important nuances. And we're gonna start at the bottom of this tumor by exposing the foramen lacerum bilaterally. And that allows the initial opening. So first thing I did, all the way down, I found the foramen lacerum. I found the pterygostenoidal fissure, which is so useful. I find my choroid artery at the foramen lacerum and then I can just follow it into the cavernous sinus. So I go from the bottom up as opposed to from up down. And then I'm now removing the middle wall of the cavernous sinus that is widely invaded. You can see it's the CCL also that is embedded by tumor and coagulating it. So I'm gonna enter into the superior compartment of the cavernous sinus. I identify the intercranial ligament, kind of the space above, oculomotor triangle behind. I know the oculomotor triangle is behind, so the tumor piercing through is gonna be there. You can see the arachnoid there. And now I'm working the posterior compartment of the cavernous sinus. Now working supracellar, wide neural opening to get access. And then you see the optic apparatus, very widely invasive tumor. And then this is the PCOM right here and the third nerve. And you see still tumor going to the dura. And I'm going to find this tumor. I'm gonna cut the dura towards the oculomotor triangle so I can completely remove this tumor. And in spite of the third nerve looking that way, this patient did not have a thernopalsy post-op, not even ptosis. The third nerve is sometimes so resistant while she had a six nerve palsy after the operation that took a while to recover. But you can see here our complete resection. That's the pituitary stalk and the pituitary gland. And sometimes pituitary surgery is like this, you know, a very aggressive operation. This is the sixth nerve here in the Reynolds canal. But this patient had severe ptosis disease. And the only way to really get the disease in remission or under control is with an aggressive operation like this. And this patient actually had a cortisol level of two. So she crashed two days post-op with, you know, surprisingly good outcome from an endoclinical point of view. So just to finish, you know, endoscopic Indonesian cavernous neurosurgery requires deep knowledge of the anatomy, in particular of all the different segments of the coronary artery. You need to have the 3D anatomy of the coronary in your mind when you're operating. Segment by segment, ligament by ligament, compartment by compartment. And to summarize, you know, just remember the principle of pituitary surgery, how important it is. Identification of clonal space and CCL, middle orbit section and the different patterns of invasion compartments. When we talk about the cavernous neurosurgery, the pretossal process for amyloid serum. And finally, remember how going from the lab to the OR has allowed us to get into improved remission rates and outcomes for pituitary patients. Thank you very much. Juan, fantastic presentation. I think Dr. Rodden would be really proud if he was still alive with you really exemplifying the three principles he lived by. So we'll hold on to questions for now and we'll move on to Dr. Evans with reconstructive techniques. Thanks so much for inviting me to participate. I also want to congratulate Juan. You just impress me all the time, Juan. I've known you for many, many years, I think, since you were with Al Rodden. And I know you stand on your own two feet, but I also want to congratulate you on carrying on his legacy. So I so much appreciate all your work, Juan. It's always a pleasure to watch. Thank you. Thank you. I'm going to share my screen. Yeah, so thanks again so much for inviting me to participate. I'm Jim Evans from Thomas Jefferson University. And I was asked to address reconstructive techniques in pituitary surgery and beyond. And in a short time, I'll try to show you a little bit about that. This is our university in Philadelphia and this is our center. And my disclosures, but more importantly, my disclosures number two, which is that there are just so many techniques to perform endonasal repair of the cranial base of these defects. And there's way too many to adequately address in a short time in a presentation like this. But this presentation will present sort of my personal perspective and experience looking at these repairs and sort of our philosophies with how we do it at our place. And these are some of the pathologies. I took to heart this concept of repair of the cella and beyond. And I really want to take a chance to address this. No matter where you come from and all the neat surgery we see and aggressive operations and everybody wants the next coolest operation, this is really still, as you saw with Juan so elegantly, the mainstay of a lot of what we do endoscopically. And even for the expanded and extended approaches, really a lot of it begins at the cella, at the sphenoid as you've seen. And so I think it's really important to look at this and we can approach it from a maximally invasive or minimally invasive way. And I try to minimize a lot of the approaches in a way and minimize destruction and try to even keep the repairs somewhat simple. So this might be a little bit different from what you might be used to seeing with repairs. And then we'll go on and talk a little bit about some of the more expanded approaches. So microadenoma, this is just my illustrator's rendition of this kind of an operation, this idyllic little old field type dissection with an extra capsular dissection and eventually on-block removal of this little ideal microadenoma. And this is how it might look in surgery with this dissection, just kind of extra capsular respecting the planes of this tumor and eventually achieving an on-block removal of the mass and trying to get the best chance for remission of that little tumor. And then this is sort of my rendition of a repair for something that simple. And I'm not sure if you do this at your centers but I just use a piece of surgery cell for that type of thing. When this gets a little bloody, it sticks quite well. We know it creates a little bit of an acidic environment but actually I find the mucosa grows rather rapidly across this and I'll show you some post-op videos for a lot of these kinds of cases. And I think this is simple. It prevents the need for other incisions with fasciolata or fat, prevents the need for packing or expensive grafts and glues and maybe nasal septal flaps as well with the inherent potential morbidity. And this has worked very well for me. And this is the kind of thing where just the same kind of case with just a simple piece of surgery cell. And again, nothing really fancy or expensive but it heals quite well and it works well for me. And let me see if I can show, this is what that might look like just post-op. Look inside, I'm gonna see if I can jump ahead to the end. You look here, again, this is early, it's just a week post-op. But if you look up inside this cavity, you'll see things are kind of healing a little bit hyperemic, et cetera. And you'll see this thing is kind of still pulsing a bit. It doesn't look so great. But if you look at it just, here's this, I just switched ahead. This is now three weeks post-op. Same exact case looking up inside. Again, things are still healing. It's only three weeks. But look what the cell looks like at this point. It's pretty well healed. It's mucosalized and this is early yet. There's still a little bit of debris and things that has to be cleaned up. They still need to irrigate a little longer. But just at three weeks with a simple thing like that, that heals pretty nicely. And that's worked well for me for many years. We've published this in 2019 and looked at a huge number of cases and our leak rate was 1.1%. The caveat, the important thing here is you need to recognize an interoperative CSF leak. If, you know, this is not intended to stop a CSF leak. So if you don't, or you can't recognize the interoperative leak, then you need to do something more robust. But if you've got a very clean removal and diaphragm's intact and things are pretty straightforward, this repair is very, very effective to heal, as I've shown you, and it's very cost-effective. So macrodinomas, we'll just switch gears. You know, some of these are very soft. They've got some poorly developed pseudocapsule and we've all need to have some kind of mechanism for removing them, some methodical way. We use our binaural approach, as you know. We won't belabor that, but some way to get to this point of having a gross total removal. As you've seen, maybe that involves a cavernous sinus. It's on our, in Juan's presentation. But anyway, to achieve a gross total removal, you see our diaphragm kind of coming down like that. And this kind of thing, it might look like at the end of surgery. Some may have a firm and very well-developed pseudocapsule. And we want to take advantage of that, whether that's an entirely circumferential pseudocapsule or whether it's just in some areas, whether up against the diaphragm or elsewhere. And whenever you can take advantage of a pseudocapsule, do so, as long as you can separate it well from the gland and not perform a hypothesectomy and still mobilize it and remove it from the diaphragm, et cetera, try to do so. This is just a brief example of that kind of thing. I showed this once in an endocrinology meeting and everyone said, hey, we want to do pituitary surgery and just pull these things out. But then it all go this way, but this is decompressed centrally and now just kind of mobilizing this capsule away from the gland, which is sitting right on the side and the diaphragm up above. And it's really not, this isn't meant to be a resection kind of case, but mainly to show that when that's removed, you can have this diaphragm all decompressed like that. And this is the same case where you see the gland is preserved, the diaphragm here, and there's no leak or problem, but we need to know how to repair it. And that's sort of the point of this presentation. So even for many macrodenomas, if there's no CSF leak, and if it's not a giant decompressed or patchless diaphragm, one of these diaphragms might, you know, herniate out and have some potential morbidity. I'll often repair, you know, small dural opening, et cetera. I may just repair with a piece of Surgison. I think it works quite well. If you've got a leak, that's not going to do it. So we need to advance our repair a little bit or a very patchless diaphragm. And you've seen these from these huge macrodenomas where this diaphragm is just coming out, looks like the throat of a frog sometimes, just kind of herniating out and they can actually rupture and get snagged on little bits of bone, et cetera. And CPAP, we'll talk about in just a little while. But when we get into this kind of thing and postoperative CPAP use for OSA, then I want to get a little bit more robust repair. That's where I may go to a dural substitute and some biological glue. And this kind of thing, where you see this little picture here, this MRI with this diaphragm be all kind of herniated out, we'll put an inlay graft like this, something a little more robust. I'm not sure for CME purposes we can name the grafts, but nonetheless. And then some biological glue over the top, kind of like that. It's a pretty simple kind of repair. It doesn't need a buttress or anything packed inside and that sort of thing. And that's what this would look like at the end. And the sphenoid should be well-preserved. This is an older picture. I really try to preserve all the mucosa as well, as much as possible, without stripping the whole sinus, et cetera. And this kind of thing, you can use this for these big tumors. You know, it's a pretty large obelisk kind of tumor. And here's the post-op. You can see nice resection, one of the cavernous sinus. But a nice repair of the dura will be fine. And you can keep this very, very simplistic without needing to be overly aggressive with flaps and everything else. And so I just want to impress that upon the people that are watching, especially if there's any younger surgeons that are going to view this, that you can do this in a very simple way and still get good outcomes. Oh, let me skip back. And so that's this thing is just putting that repair, it's kind of an older video, but just showing that kind of grafts being placed. And if this is not a leak kind of case, all this is meant to be is just a buttress so that the diaphragm doesn't herniate down. If it's a leak kind of case, you really need to get this well approximated, but the synthetic graft like that kind of sits in place pretty easily. And then some biological glue on top, which I think helps. I think the glue is probably the least amount of the whole repair, but I think it probably does help a little bit. Probably a little bit of blood on these edges can do just as well, quite frankly. But a little bit of glue on like that, and that'll stabilize that graft without any real kind of packing or things like that. And that works quite well. And then, so this is going to be the same thing we'll look at here post-operatively, just briefly. Still, this is one week post-op. We keep very careful videos of all our cases. You'll see that's still a little bit hyperemic, et cetera. I skipped ahead, sorry. But it's still a little bit hyperemic. You'll see that glue is losing its color. It's still kind of sitting in place. That'll just dissolve to water in a short time. And then that mucosalizes quite well. And we looked at this as well. We just recently published this in 2020 with a large number of these cases with just a single layer and some glue like that. And our leak rate was 1.2%. Most of this was early on in that series. Once you learned how to set things up, these leak rates are exceptionally rare now to see post-operatively from that simple repair. And that's with the CSF leak intraoperative as well. And then this is that kind of thing with the macrodenoma, that sort of repair. You can see this is a big expanded cell, nicely repaired. There's really no packing or anything in this unit. This unit's kind of small to begin with because the cell was so expanded, but just that simple repair. And I think a well removed tumor and an effective repair. This is a different story with OSA or obstructive sleep apnea. This is something we've studied quite a bit at our center and the use of CPAP. And we studied all these repair techniques in a morphometric analysis that we published a couple of years ago. And these repairs actually are quite robust. This repair with that synthetic graft and some biological glue will hold back easily 18, 20 centimeters of water. It won't breach. And so it's a quite effective thing. We're in the process now of doing a prospective clinical trial, studying the same thing, looking at various pressures and the various repair techniques. But suffice to say, this can work quite well. It's a whole different animal though when you're dealing with OSA patients or acromegalics, et cetera, that maybe need some additional attention for their airway and for their repairs. So other repair options to be fair. These guys were the leaders naturally from UPMC in Juan's old place and showed their repair early on, published their repair with an inlay and onlay graft, a fat buttress and biological glue. But importantly, this concept of placing a balloon stent, some type of a balloon to buttress and hold this thing in place. And this seemed to work very effectively for them. It's not something that we use at our place, but they've published this and used it I think for a number of years. The guys at Cornell, our crew with Ted and Vijay, et cetera, up in Cornell came up with a very creative way of using something called a gasket seal. And I'm sure you've heard of this or maybe some of you use it, which is basically using a large graft, whether it's fasciolata or synthetic, which is shown here, and then using some form of a rigid buttress that's countersunk inside. And that may be a piece of bone from the septum or the vomer, a piece of titanium, like a sheet of titanium or a piece of titanium plate or a burr hole cover or even med pour. And then kind of countersinking this, kind of wedging it in there, which I've never been enthusiastic about wedging something in with the anatomy in that area. But then utilizing Duracell glue or some sort of glue over top, which is by their paper, but importantly a lumbar drain. And lumbar drains are used exclusively. And so this series has excellent outcomes with CSF leak, low rate of CSF leak, yet I'm not sure this is entirely related just to the repair because it's confounded by some of these other mechanisms like using a lumbar drain in each case. I don't know if that's a fair assessment of the repair alone, but however they're doing it, it seems effective for them. So a summary of like how we're doing things at Jefferson in general with our algorithm is surgicel. It's our mainstay for many pituitary adenomas, certainly the micros as I showed you in certain macros. If there is a thin, prolapsing, you know, this sort of patchless diaphragm I described or a leaking diaphragm, then we tend to go to this inlay dural substitute with some biological glue. And again, that works very effectively for us. This kind of thing, if there's a big tumor and the diaphragm is just destroyed, you've seen some of the cases where like Juan's got it all wide open and a large dural defect, et cetera. We can talk about high and low flow leaks later. Then we'll go on to this button graft. And I think I'd be remissed in any repair talk to not talk about my beloved button graft at least once or twice. And you'll probably hear it three times here, but in any case, this bilayer graft that we use at our place, and we've used it for many years, very effectively. Mark Rosen and I came up with this many, many years ago, working together and it's effectively a bilayer repair with the two layers sutured together. It's got a lot of advantages. We find you can make this autologous or synthetic and they can work almost equally well if they're covered by mucosa, but it's very stable. This will double the surface area for healing naturally. It conforms to defects that have multiple planes. Like when you're going along the plane, I'm in the cell, et cetera, down the cell and the clivus, and it can conform to these things quite well. It doesn't require bony edges, preserved bony edges necessarily. So you don't need to limit your opening in order to utilize this. And importantly, it doesn't require any kind of a buttress per se, like a gasket or a bony buttress to kind of hold it in place. And the most important thing I think is that you can use it around delicate structures. We can tuck this around the optic nerve or the ICA or that sort of thing, and very nicely kind of get coverage and I think good prevention for CSF leak yet not need to buttress or put something firm or anything that would cause pressure around these structures. And so this for like these destructive kind of cases, these so-called high flow leaks, invasive tumors, something like this where you may have a third ventricle that's going to be wide open in the end of this and may require some additional repair with the nasal septal flap. A couple of things about flaps, again, we don't have to belabor all this, but we know they're based on the senopalatine artery. There's all kinds of renditions for this flap, of course, but the basic thing, the mucoparous, mucoparicondrium, it's kind of our workhorse. A couple of things that you bear in mind is you can make this flap very wide, and it can be helpful sometimes to come down the lateral wall and make a slightly wider flap, even if you don't necessarily need it. You know, the tendency is to be real careful with the olfactory mucosa above and try to stay above the decassating fibers below, if you believe in that, and make this sort of thin kind of stick of gum or some kind of narrow flap that might be effectively covering your defect, but sometimes tends to fall away from the anterior cranial base or fall away from wherever you're using it. And so sometimes having a slightly wider graft, even though you've got to prepare the recipient area a little bit better and maybe remove a little more mucosa widely, it tends to sit like a dome. It gives a little bit more structure to it. It tends to stick a little bit better without the need to pack a lot of things up against it. So that's one thing is pay attention to how you configure it. Maybe you've got damage to the septum or you've got a big spur, other things that are going on here, or even cancer that's involved in the septum, and you may need to expand down and go a little bit wider and involve some of the lateral structures under the turbinate to the turbinate itself. The other thing is coloring it purple or whatever color your skin marker is for surgery. We tend to color this thing, and I'm not sure if I pressed that upon you, Varun, when you were here, but we tend to color it. It kind of helps to prevent it from getting twisted. You know, we know for a fact that it's been, and we've all probably shown it one time or another, you put it up backwards, it doesn't work. And if you color this thing, it kind of helps orientation. If you're late in the case, it's kind of swollen. You may have your fellow resident or someone putting it up and practicing, you're less likely to get it twisted. You know, you can pull it up the septum and kind of line it all up again, but I think coloring at the beginning sort of helps. And you'll notice we color things like our button and stuff. If you see any of the videos I'll show you later, just for orientation purposes, that's something you might want to try to utilize. It's just a simple and I think effective thing to use. And this is just a cartoon of the flap going up. So this is something that's important to maybe save you some trouble. If you perforate or lacerate your nasal septal flap, many times if there's a large spur, sometimes it goes all the way to the lateral wall, or it just, you have some technical difficulties mobilizing the flap and just redo, or you just knew it doing it and you get a perforation or a laceration of that flap, you can still utilize it. You don't have to abandon that. And in fact, we tend to take our flap on the more difficult side. So the side that's got the spur, got the deflection, got the more difficult mobilization. And of course I work with a guy that's just a real master at doing this. I never say that to his face. I always joke, but Mark Rose and my colleagues is a true master, can make a flap out of anything. And we tend to take it on the more difficult side because we're not so much worried about causing an injury to it. We looked at this some years ago in 2015, and in a series of these cases that had some form of perforation or laceration, we had no increase in our leak rate utilizing the flap. It just need to place it well. And you'd be careful where to put that perforation. In fact, you think you don't want it near the center, but if you've got a primary door repair, I will put the perforation right in the center of it because it's the edges of the primary door repair that are more likely to leak. So you don't want your laceration there. If you've got to configure a flap, that's got, you know, maybe a tear in it, or if you've got a perforation somewhere, you can't get it way off to the side, put it dead in the center and you can position it kind of carefully and close that up pretty well. There's ways of suturing the flap and getting creative to close these defects if you need to. And we've got techniques for that as well. But suffice it to say that you can utilize this flap nonetheless if you have a perforation or a problem. So again, this is just a summary of our various repair techniques. Now the CSF leaks, I'll be honest, there's a lot of classifications out there, right? And we can get as scientific as we want about it. And everyone's got their own, I don't know, there's some that are followed more commonly, but some have to do with the size of the defect. I think that's pretty, pretty acceptable. This so-called rate of flow, high flow, low flow, medium flow, medium high flow, I find a hard time determining what the heck that even means half the time. And I don't mean to sound so simplistic or crass, but that's bizarre to me. And then this concept of pathology, right? So that makes good sense. It's a tumor, pituitary tumor, or it's a high pressure kind of pseudotumor case or whatever the case you're dealing with. And then I think this concept of direct or indirect, meaning like through arachnoid, through a diaphragm, that's one thing, you know, through a cistern, different than when you have like a, like a ventricle wide open and there's something pulsing directly on your repair, which I'll show in a few minutes. I think these are things to take into consideration. I don't have the answer for this classification, but I have some ideas about it. This is one way to think about it. This sort of defect size, I think is very important, a small defect versus large, simple as that. If we look at a small defect with sort of normal pressure, what are the cases you see that in? Well, pituitary adenomas, right? Little hole in the diaphragm, whatever it is, that's going to be sort of a normal pressure, sort of normal flow. I don't know. Low flow is the right term. That's sort of what we throw around or like an iatrogenic leak from functional sinus surgery. You're going to have some small thing. You can put about anything on that. It should heal up pretty well. Small defects with high pressure. Maybe this is the high flow case. And I think that makes sense. There's little leaks from meningocephalocele. Patients with IAH, idiopathic endocranial hypertension, or pseudotumor cerebri, this kind of thing is probably high flow, right? Tiny little defect and brains herniating out and CSS flying out behind it. That's something I think. And then this concept of these large defects, right? These more expanded approaches we take. Probably mostly normal pressure. I don't think you want to get into doing a big expanded case in someone that has IAH or some high pressure or hydrocephalus. You better deal with that issue first. But this is that quote unquote high flow situation I think we refer to, right? Big dural opening, maybe the ventricles open, things that are going to kind of come kind of pushing at us. So that's my spiel about micro and macro adenomas. And we can talk more about that or at the question answer thing. And this has worked pretty effectively for us. So some of the expanded things, and this takes a little bit more, I think, creative repair, but you'll see a kind of recurring theme again as I push my button graft. So, you know, the early limitations with all of this expanded surgery was really the cranial base repair, it seems, in the very beginning. And we have people like Juan that are masters showing us new ways to open things and unzip this area more and more and more. But the big thing was the repairs that held us back, right? And there's these loads of different grafts that were used in the beginning. We were all trying. In the very beginning, there's a few of our centers that were doing all this stuff and all these glues that were coming out one after another. And then we all tried free autographs and these pedicle autographs. And of course, the nasoceptive flap is more of our constant. And then all sorts of suturing techniques. And we were trying all this stuff in the beginning as well. And there's probably about as many, as you can imagine from this presentation, about as many ways to repair this cranial base and techniques as there are centers that do this surgery, right? There's gazillions of ways to do this. But there's a sort of common theme in general terms for this sort of expanded cranial base repair. And what it is is some form of a primary dural repair, stable primary dural repair, whatever it is, button gasket thing, whatever, and covered with some sort of mucosa, usually vascularized pedicle mucosa, but some sort of mucosal coverage. And this is kind of a common theme, at least in most of these kind of repairs. Again, back to our button graft, my beloved graft. The inlay, we often make 25 or 30% larger than the defect. It can sometimes shrink a bit. It gives a good surface area. And then this onlay that we'll make just slightly larger than the graft. And the reason behind that, I mean, larger than the defect. And the reason behind that is when I put my mucosal coverage up, I don't want to just cover graft. I want that to lay up against, if I can, some normal dural edge. I think that vascularized dura and a vascularized graft touching together heals quicker than anything you can put in between. So I don't tuck bone and things in between the two. I think that works quite well. You shouldn't have a big herniation in your cranial base, except in a couple of circumstances. And most of that is due to high pressure. If you come upon it, there's some lower herniation down in the clivus you can sometimes see without high pressure. But this kind of idea, these are sutured together with two or four, four neuralons, however you need. And you can make this as large or small as you need. This is showing pericranium. Oh, this is a video. This is after taking out a big craniofringoma. You can see up in the third ventricle, et cetera. And this is just, I'm going to skip ahead from the removal. I don't really care so much about that and all this grafting. Just to here. So this is just kind of suturing that graft from the back table. Pretty simple. It's not done inside the head or inside the nose. We suture this together once we've made our measurements. And then it's going to sit in place. This is showing the anterior cranial base, but it'll sit something like that. And then the graft will kind of come in place. And this is sped up just to save time, but we're tucking in that inlay graft. And I've got little dissectors to help me make those angles. And we kind of work our way circumferentially around this. It really doesn't take long, even though this is sped up a little bit. We tuck around each edge to make sure this is seated nicely. And you can actually grab this onlay piece and move it back and forth. I'm just going to pause that for a second. You can move this back and forth a little bit to get that inlay to kind of unfurl if you're having trouble tucking it in, depending how big your defect is, or if you're working around any critical structures. And then that'll sit in place. And this is colored purple, again, just for orientation, because if it's a little bloody, et cetera, that paracranium can look just like dura. And if I don't color that with purple, if I just stuck it in and showed you a video, it looked like pulsing dura once it's really settled in there. And so I'm going to kind of continue here. You'll see that gets kind of tucked in place. And eventually when it's seated, we won't see CSF coming around the edges and that sort of thing. This is usually nice and flush. It's probably not the greatest example, but it'll sit and you'll see when it's not leaking and it's pulsing, it's in good position. And then we'll cover that with a nasal septal flap. And that's not the reason for this exact video. So we'll skip ahead, but a little bit of biological glue. And occasionally if I need to put something in, I might put a piece of nasophore just in the center, just to kind of buttress things and that'll absorb. This is showing it going in, we'll put it in the middle meatus as well to keep the middle turbulence medialized. But nasophore can be helpful and it melts down, as you know, to just like slush in about a week, you can suction it out. So it's nothing permanent. Synthetic grafts work quite well also. When we first started out, this is what we were using for the cranial base. So leak rates were certainly higher. And this is before we were utilizing at our center, the nasal septal flap, we started using that back in 2006 or so. But prior to that, we really relied on just our button graft alone and the standalone graft actually healed pretty well. And I think, I'm not sure what we're showing here. Oh yeah, this is just like a synthetic graft kind of going in place to kind of being tucked in here. And I'll just skip ahead a little bit. We don't belabor that, but this is just an older synthetic pure button graft going in place. You see when it sits, it's pretty nice. It sits down nicely. It's just a flap being put up across it to kind of cover it. So we'll skip ahead on that, but the synthetic graft can work well. And if you're covering it with a good vascularized pedicle mucosa, synthetic graft is probably sufficient and you can avoid the need for taking fasciolata. And these giant recurrent invasive tumors as well, you know, a little bit greater likely to leak. We wrote this paper a few years ago and our leak rate with the giant edema was only 1.8%. So I think that's acceptable for these bigger tumors. Rercum, Settlement, and Jomas, we've studied as well. You see nice basal septal flap. There's a button graft just behind that. And we've, we wrote this up to a while back. And craniofringomas, this is the, this in the beginning was one of the more troubling ones, I think because the ventricles are wide open off and you get a big tumor like that, and you've got a third ventricle and aqueduct, everything wants to kind of pulse and work against you for your repair down below. And you can, you see there's a different one, but same kind of concept. It's kind of shows that big open cavity you have. There's a button graft kind of tucked in here and a nasal septal flap and maybe a piece of nasophore. But this actually heals quite well and it's been very effective for us. We studied this some years ago and our leak rates with this were 4% in the first part of the series down to 2% as we go along, because we're not seeing the leaks so frequently any longer and we got better at doing this. So this number, I expect to keep getting smaller. We're just in the process of another analysis. Stabilization, we talked about, nasophore I think works pretty well. There's a firm nasophore that we use, also for medializing our middle turbinates. I think it's a good repair for the central part of one of these large grafts if you need it. And again, it melts down pretty quickly. Balloons, we're not a big fan of. I think there's too much risk for mucosal damage and ischemia of the flap, potentially. We've seen alone necrosis with patients that had these put in elsewhere with the nose was kind of necrotic. We had to kind of work on that and it can be painful to some patients. I'm not a big fan of balloons, but it works effectively for others. These are tricky clival defects. This is a chordoma, as you can see, that's got an intradural component going along the basilar artery in the brainstem you'll see here. And that's kind of, you know, my illustrator's cartoon of that, but just briefly to show this chordoma, I think you'll see some pictures here. You'll see how it's expanding intradurally. We're going to have a big defect here and a high risk for leakage. I guess you'd call it a high flow leak, but here in the interpenuncular fossa, etc. And I'm not going to belabor the removal. I'm just going to, I want to jump up to find the defect if I can. So there's the defect, the dural defect, partly created by the tumor. We're going to have to make that wider. I'll skip ahead because we already have a lot of the tumor on. We resect the dural all around here. We've got to take it off the basilar and everything else. And then eventually we're going to have this defect left. You'll see the basilar here. Again, not an anatomy lesson, but we will measure this defect out with a caliper. In this case, I'm using a pituitary just to get a sense how big the defect is. And then I configure my button graft. Again, I'll make it larger on the inside and just slightly larger on the outside. In this case, on occasion, we make it equal size. If you've got good bony edges, you can put a piece of buttress in here if you need it. I don't find it's necessary, but if you're worried about the, you know, pons herniating or things herniating forward, which has been reported in the literature, you could put a buttress in here if you've got edges of clivus left, if you're concerned about that. Otherwise you can put soft tissue for a dead space. But you'll see that'll get tucked in place. It begins to pulse nicely. We're not seeing CSF coming out everywhere. And then our flap kind of goes up on that. That's nasoceptal flap. And we're sort of pushing it down to reduce dead space. And I'll talk about that dead space in a minute. And there's the flap in place. You see, it sits nicely. It's like a big dome, a little bit of biological glue, which may again be superfluous if you've got blood along the edges, but we use it nonetheless. And then some nasal pore, maybe centrally, and that's it. And that repair works well. And I'll show you, I don't know if his post-op's coming up in this video. Yeah. So there's a post-op, I think I've got it next. Yeah. So this is the pre-op of that same case. Here's the post-op. You can see a nice removal. We've got a button graft in place, some gel foam in here. If you have a big dead space, you might need fat or gel foam, and then a nasoceptal flap. This is one of the rare places I would use fat previously, and now often just a piece of gel foam in that region. And this kind of thing where this is just a cartoon of that, or the illustration, I guess, on an MRI scan, showing that bilayer button graft in place, this thing we talked about. And then fat or some gel foam, often gel foam now, if there's a big deep defect where your nasoceptal flap won't necessarily sit all the way down inside, you may need to put something there so you don't have a dead space. And then the nasoceptal flap might sit something like that. And this has worked very effectively for us. The question of lumbar drain, the age old question. So we're not big fans at our place. This is a very well done paper, I think by the group at UPMC. Once again, looking at the randomized use of lumbar drainage, and they found that it reduced their leak rate from 20 some odd percent down to 8% when it was utilized. So they've used this effectively at their center and other centers use it as well. We do not, we don't tend to use lumbar drain either primarily as part of our repair or as a salvage when someone comes back with a leak, we tend to go back and repair the leak. But this is just one example of that. And just briefly, a few other repair options, TPF, pericranium and free flaps. So this temporoparietal fascial flap is very useful. It's a very familiar flap to head and neck surgeons. It's used for a number of reconstructions, microtia repairs and static slings for the face, temporal bone defects, et cetera. And it's a very, very versatile flap. It is contiguous with the SMAS and the galea and it's pedicled off the STA, the superficial temporal arteries you can see here, kind of like that. And you can get a very big graft and this is a pretty robust thing that you can utilize, especially for these lower defects if you need. There's some great advantages. It's constant anatomy. It's usually there unless someone's had a craniotomy or something else to their head. It's got a great arc of rotation. It's got a very long pedicle. It's pretty resistant to infection. It's a robust thing, even though it can seem thin. And one of the important things about this is you can fold this thing up and use it. You can wrap it around vessels. You can fold it and use it and put it in places. You can tuck it in. You don't have to worry about like a mucosal layer and that sort of thing like you have with a nasoceptal flap. So you can get very creative to utilize this flap. Disadvantages, there's a bunch. I mean, there's a big incision. This has been tried to be harvested endoscopically. We've all experimented with that, but mostly you got to use a coronal incision to take it out. There's a visible scar. There's potential for alopecia, because you're taking a very thin resection up against the skin. You got to be careful on your frontalis branch, et cetera. So there are some disadvantages, but I think it's a very effective flap if you need it. We studied this in our lab in a morphometric study we published a year or so ago, looking at the size flap you need to cover various configuration and size defects in the cranial base. And so you can look at that if you're new at doing this or you need some input about what size to make. Endoscopic pericranial graft. This was very well published by Adams Donation and the group at UPMC, once again, that were utilizing this flap and trying to harvest it endoscopically. So it's sort of unilateral flap, unilateral pedicle, using a couple of small incisions to harvest. Again, most people, if they have to get to this, are going to do a coronal incision still to adequately harvest it. This was a challenging thing to do well endoscopically just based on the curvature, et cetera. But nonetheless, it culminates with a glabellar drilling to have access and then pass this flap into the nasal cavity against the anterior cranial base. And this can be an effective salvage if you get into a jam. And then the ultimate salvage kind of flap are free vascularized flaps. And this is just one example I'll show. And we've got a series of these for various things. But this is a nasopharyngeal carcinoma that developed a delayed osteoradial necrosis, a pretty bad one with the clivus eroding it to the dura, et cetera, and had a prior craniotomy on one side as part of the primary treatment and had an attempted TPF flap on the opposite side and didn't have an adequate nasal septum. So you're kind of running out of things to fix this cranial base and expose carotid, et cetera. And so in this case, we used a radial forearm vascularized free flap and you'll see the graft here with this nice long pedicle, which is helpful. Caldwell lucked to deliver this in. And then we were looking for angular vessels here and eventually ended up using the facial vessels down below. But again, the advantage of having this super long pedicle if you need to have some reach to access vessels. And so you can put this kind of thing in and this is the pre-op and then this post-op. You can see this nice graft. This will shrink a little bit over some time, but sitting nicely in here. And this vascularity can help this concept of trying to treat the osteonecrosis as well, which you'll drill away as much as you can back to healthy tissue. But this vascularized tissue does help that to heal as well. And so these salvage flaps can be used for a number of different defects if you get in a real jam, but you need to have a good team to work with that's very facile at the various types of flaps. And I'll stop there. So thanks very much for inviting me. That's my sort of A to Z about repairs in a very short time. And I'll be happy to answer any questions or that sort of thing. Thanks so much. Dr. Evans, that as expected was a tooth to force through scalp-based reconstruction in a short amount of time. I certainly myself learn a ton even just listening to you right now and really exemplifies how with experience and with mastery can sort of be simplistic in things that need to be simple, actually avoiding a lot of the morbidity that comes with just going all the way and actually using the big guns where they're needed. So I think we are gonna go ahead and go over some of the cases and then we'll save some of the Q&A for the end. Again, please, for our live audience, please go ahead and place your questions in the chat. And we'll get to them as soon as we're done. Or as they come, we can address them as we go. So this is the first case was a case that was submitted. And it's a case actually that's not been addressed yet. And we would like to see what Dr. Evans and Dr. Fernandez would do about it. It's a patient, it's a 53-year-old who was actually diagnosed with acromegaly, had consistent lab work. It looks like with an IGF of 800 almost. And had consistent physical features of acromegaly with prognathism, had a visible septal deviation and large in fingers, feet and facial features, et cetera. These are the images is actually a scroll through MRI. This is some of what we're concerned. You can likely see better here on this coronal, there's an obvious macrodenoma. Maybe definitely a budding, there's medial wall here, but questionably invading the cavernous sinus, likely not invading the cavernous sinus based on this picture. The curvable to it is that there seems to be on the ipsilateral side, it seems to be this small superior hypophyseal likely aneurysm. And the patient actually had an angiogram, there's a 3D rendering of an angiogram. I guess we'll give this to Juan. Juan, how does this change your management? Or does it change your management? Is this something you would a priori plan to resect the medial cavernous wall? What would you discuss with the patient? Tell us a little bit about your thinking. Okay, so first let's forget about the aneurysm for now. Well, there's the second round, but just if you look at this tumor, tumor size looks like an easy tumor, but if this is a gonadotroph adenoma, it's a complete different scenario that this is a grothmaldenoma. Because if this is a grothmaldenoma as it is, the chance of the medial wall being invaded are quite high. I would say more than 50% based on my experience. So I would be going in, exposing the interior wall of the cavernous sinus so I can have very good visualization of the medial wall and be ready to remove it if needed. Now, the patient has an aneurysm, so that's a different scenario. So I wanna address that first. So I could do an angiogram and I would talk to my vascular colleagues to see what their recommended treatment for that is. And we'll go from there. Well, the issue with this aneurysm obviously is that the endovascular treatment of them is a pipeline and the pipeline requires aspirin pipes for six months and patients really cannot come off their aspirin forever. When they come off the aspirin, there's significant risk to them thrombosing the stent forever for life. And that's the complicating part I guess here is that if you do place a stent, it really complicates things. This is intradural. The aneurysm is this one right here, right? It's this one right here, right? Right here. So it's a supra-alveolar aneurysm, correct? Okay. So that's clearly above the distal ring. So it's clearly intradural. In that case- It's very close. How worried are you about this with an exposure that you would resect the medial wall? I don't think I would be worried because it's intradural above the distal ring. Okay. So you would proceed with surgery normally. You wouldn't do anything else for the aneurysm at this point. This is actually not an aneurysm that needs to be treated from an aspirin. That's what I was going to ask you. Does that need, does that have any history? Does it have any kind of morphology that would suggest it's a rupture? This is just an incidental, happened to trip on it? It's like it's just incidental finding on an MRI. Yeah, that's a tricky, that's a, I'm sorry, go ahead. I don't mean to cut you off. No, no, I didn't, I was saying that, I guess the real question is here, does it change the surgical thinking about the management of the adenoma? Dr. Evans, what do you think? You know, I would be worried about that. I must admit, you know, I like to think I'm pretty calm in surgery, but I'd be concerned about dissecting around with that aneurysm nearby. I think that's intradural. I don't think you're going to be necessarily right on it. I think if you're cautious and you're not going to kind of bang up against it, what's the risk of it rupturing though with some dissection either nearby or manipulation of it? I don't think you have any data to support that whatsoever. And I don't think you can claim it. You can tell me about the natural history of that rupturing and your risk of stroke, treating it, et cetera, but I don't think you have any data as to what that's going to do if you manipulate the carotid nearby it, or if you manipulate the dura up against it, you're in the cavernous sinus up against it, taking out the medial wall, whatever the case is, even if it's intradural, even if it's purely, purely intradural and on the other side, I don't know that we have any data for that. You're really in some uncharted territory, I would think. The option would be to treat it, to secure it somehow, right? Typically you'd probably want to pipeline that. You're probably not going to coil that easily. I don't know what its neck and everything looks like, but if you had to pipeline it, you're right. You've got a problem, whether you believe in Plavix for three months or six months, but Aspen's going to be a player. And that's going to kind of complicate things a little bit. So that would take a lot of discussion, I think, with our, we have a very robust endovascular group you might know here at Jefferson, and that would take a lot of discussion about how to best manage that. I think you could operate the tumor that should be an intradural situation. It should be separate, but I think you'd have to have some caution. And again, I don't know the rate of that rupturing with removing a pituitary tumor that's conceivably up near against it, or right nearby it, or whatever the case is, and then getting into this concept of perioperative management, blood pressure, et cetera. I think you're in a little bit of uncharted territory. Yeah, I think, well, I'd be interested in what Dr. Setry thinks as well. Dr. Setry is a vascular. Yeah, I was just going to say, you know, the alternative is it didn't look like there was chiasmal compression. It's more symptomatic from GH production. You know, if you didn't want to pipeline it, I think you could, you know, delay surgery, you know, nine months or so. And I think at that point it would be reasonably okay to come off both, to be frank. I'm curious in talking to Juan or Jim, if you think pretreatment affects the resectability in any way. Pretreatment with, you mean with somatostatin analogs? Somatostatin analogs, yeah. Oh, I think my pretreatment of the aneurysm. I misunderstood you. No, yeah, no, pretreatment. Let's say you treated for, you know, nine months with the somatostatin analog and then at a later point went in for surgery after the pipeline has been endothelialized and healed. You know, I do not know the answer to that. My anecdotal experience doing cases on treatment is that it looks like the tumor is more fibrous, but a number of these cases are also recurrent or previously operated tumors. So I, but I am not sure. I don't know how, I don't know. I want to make one point though, which is sometimes we operate on cases of aspirin and I have, sometimes we have to do it because they're on a stent and they have, you know, a tumor that needs to come out. So I think it's relatively safe to operate on some cases on aspirin or stop it for two days and maybe start it merely post-op. So I don't think it's a huge deal, especially if you are doing extra dural surgery. So you would treat the, let them do a stent, put it on aspirin, and then delay six months of surgery and then do it then on aspirin? No, and that's one option. I'm saying that I would have to understand what the risk of rupture is. And if this is a small aneurysm with no worrisome features, no familial history, et cetera, et cetera, and it's all intra-dural, it's above the distal ring, I think I would go for surgery without worrying about the aneurysm. Okay, yeah, this looks like it's distal to, the takeoff of the thalamus looks like a superior haplofacial aneurysm. But as Dr. Evans said, it's no far from what you would be working, especially if you're going to be dissecting the medial cavernous wall, which very likely you are if this is a growth hormone adenoma. So interesting. I think you have to add the concept of- Sorry, sorry, please. I think you have to add the concept of being in the cavernous sinus too. I agree with you on it. Aspirin's not the end of the world, right? We do a lot of our sinus stuff with patients that are kind of sick and cancer patients. We operate on aspirin. But I think in the cavernous sinus, you might say it might be a little more challenging. It's usually, you know, venous flow, put the head up, you know, some flow seal, et cetera. And it's not that big a deal, but that would play a role, I think, to some capacity. And what Rune said a minute ago, this concept of after drugs or operating on, you know, someone that's still on drugs or afterward, I do think the jury's out. We've had that discussion in international society. And, you know, for instance, that's like with prolactinomas, right? You stop it for six weeks before you operate. Theoretically, it's kind of better. And there's all this sort of old wives' tales, but I don't know that really we know that well. There's a few papers out there and a lot of opinions about it. I don't know. Do you have thoughts in that, Rune, that are strong? Have you looked into it for your case or I don't know whose this case is. No, the only two or three cases I've had of pre-treatment have been in big, sparsely granulated tumors, which tend to be, you know, more on the fiber side anyway. So, you know, who knows. And then with radiosurgery, that's another consideration, right? You know, that has some credence to not be on the drugs during radiosurgery. There is probably a little bit better information about that than there is for surgical resection. Yeah. I was also going to say, George, that in this case, removing the middle wall does not require significant manipulation of the carotid. You are removing the wall of the carotid. You're not pulling the carotid like you were having a chordoma or a widely invasive tumor. They really manipulate the carotid. So I wouldn't worry too much. Okay. Yeah, that's what I was thinking, that this looks to be intradural. I mean, it's obviously very close, but it's close, but potentially separate enough that could be addressed first and then treated with a pipeline afterwards, or even just watch the aneurysm without doing anything. So, interesting case. We'll proceed to- Juan, I had one related question. You know, how often do you find that in those cases where you're taking the medial wall that you end up having to take all the dura of the floor of the cella or the dorsum cella, or on the floor, do you, because I noticed in some of the videos, you don't necessarily take the bone out of the floor. Do you end up taking the dura of the floor or split the layers in two, or do you think that that area is not as often invaded as the medial wall? It depends on the case, right? But let's say in a case where the medial wall is invaded, I do my cut. As you know, the medial wall continues as the floor. It's the same layer, right? So, I usually cut the medial wall disconnected is what I call the inferior disconnection. I cut it along the body of the posterior glenoid, which ends up being next to the posterior gland, which is the center of the floor. So, it's a little bit off center, and that's what I cut. Of course, if I find a tumor that has invasion along the dural floor, then you cut all that dural floor as needed. But that, I think, is less common. Can I just make a comment, if that's okay? Absolutely. It's okay to say no. Juan, when you have the cavernous sinus wide open, you showed some super elegant dissections. What is your repair for that? For CSF ligament? Repair, period. Just repair. Well, let's say one that has ligament, one that does not, but how about one that's just cavernous sinus like we often do that doesn't leak? You know, often... So, if the carotid is widely exposed, the whole, you know, that you can see the whole carotid is clotinized. Sometimes I use a flap for those because the carotid is so exposed. But often, the carotid is still covered by dura of the anterior wall. In those cases, I just put duragen, and maybe glue, as you saw. Yeah. If there is no leak, or significantly. I think the problem is, sometimes you have to think about whether you have to come back, right? And that's the nature of a lot of this, is not only to preserve anatomy if you need it for later, but also just to get it open again. You know, and we've all mobilized flaps, right? You've done it yourself. I've done it too, for redos and whatnot. But that can be treacherous, trying to mobilize an inocipital flap off of the cavernous sinus, you know, at times, especially if the carotid is fully exposed. I know you want to cover it. You can't leave it open to air, but that can be kind of tricky, especially if you have a case you think might recur someday, or you might want to reoperate. You know, maybe if that recurs after that extensive operation, you're going to go the route of radiation or medication. But nonetheless, just a thought. I just was curious what your repair algorithm was. No, it's an interesting thought. I would put a duragen under the flap if it's so widely exposed. I don't think I would put a flap directly on the carotid. Yeah, yeah, completely agree, completely agree. Now, if there is dura covering the carotid, then I don't care. But if it's no dura at all, then I would put something. Good point. All right, well, another interesting case. This case was submitted by Dr. Uma Ramaswari. She didn't mind having her name attached to it. So this is an interesting case, actually. It's a 44-year-old lady with obstructive flea apnea. She was undergoing workup for Inspire placement, and she had a CT of her sinuses by her ENT. These are a real lot of pacified left frontal recess and posterior table defects. She had, on further questioning, some headaches as well as pulsatile tinnitus. And it looks like there's like a vague history here of pseudotumor cerebri. Her history is vaguely relevant other than the obesity and the obstructive flea apnea that we see here, but otherwise nothing relevant. We see her BMI is 38. There's some information here about the endoscopy, but otherwise looks like she had a normal exam. I guess she had some subtle loss of the retinal ganglion cell layer, which suggests some chronic elevated ICP. And this is her CT scan that they were worried about showing that defect in the posterior table of the frontal sinus, so in the fovea. It's relatively high and a little bit lateral. There's an MRI here as well. I'm sorry, it's not behaving as it should. But it looks like there's definitely pacifying material in the sinus, potentially encephaloceliac. So this one I will refer first to Dr. Evans since he gave us the discussion on repair. I'm just bringing the CT scan up. And what are your thoughts going through this? Well, first thing is what's your lumbar puncture show? I kind of worked up what might be IAH or pseudotumor cerebri for starters. There is information that was done, I guess, during surgery and it was high, despite her leaking. What, she was leaking, you said? She was leaking, yeah. Oh, so she's got a CSF rhinorrhea. Yeah, the CSF rhinorrhea in addition to everything. So she has this encephaloceliac CSF rhinorrhea and I think her operating pressure was like upwards of 30 at the time of surgery. So the tricky thing here is you've got a couple of things you have to address, right? So you can tap root surgery, the pressure is high. That's the, I should have prefaced it when I mentioned about lumbar drains. It's one place I would use a lumbar drain just to temporize things. So if you tap and that pressure is 50, I would put a spinal drain in just to kind of get through surgery in the next couple of days because the patient's probably going to need CSF diversion, you know, to kind of maintain the ICP. So that's one issue to kind of deal with. The other is this defect. You know, those are tricky. Posterior wall frontal sinus, no question about it, especially as far lateral. It's a hard place to reach. You can often get to that area. The issue is, can you preserve the sinus or can you adequately cranialize that sinus, et cetera? That's an age-old problem, right? That's a Wolfgang Draff and everybody just trying to figure out how do you manage that exactly? I think you could get a repair up inside there. The issue is, are you going to trap the sinus in any way? You're going to trap out your lateral recently. What do you mean? Pardon? You mean endonasal? Yeah. Yeah. I think endonasal, you could get to that region, but it's going to be tricky, right? It's going to be right at the extent of your reach. You're going to be kind of working up in a dark hole, trying to get this mucosa out of the frontal sinus. But I think you could, like I said, I'm a little biased because I work with a very creative and very skilled endoscopic sinus surgery, a sinus surgeon, actually several of them now, but particularly with Mark, my colleague I started this effort with, would try to get up inside that and get a direct repair somehow in there. Take down the encephalocele, put a dural graft inside. If you had to put mucosa up inside, the issue is going to be whether you trap that lateral aspect of the frontal sinus. But I think you could probably get a repair. I think shunting alone is probably not going to do it. If they've got an obvious leak and you just shunt that patient, I'm not sure that's going to be the best choice. You'll probably end up with some new mucephalus or another problem. And then you've got to deal with the OSA as well. I don't think that's going to be a major issue with that kind of repair. I wouldn't be so concerned about that if you put a direct repair and put mucosa in there. And then you have to get into all these other concepts of, do you go transorbital or do you go some other kind of eyebrow type thing to get down on top of that? That's all feasible, tricky place to work. I think I would try to work out a plan more in a nasal for that, if possible, if you needed a direct repair. I didn't gather that she was leaking initially. I was kind of going down a different pathway. But this is kind of obviously a meningoencephalocyte, which kind of looked like on that MRI. And she's got leakage going on. And I think you're going to have to get a repair. Juan? So to recap, transnasal with a lumbar drain to temporize potentially with CSR diversion down the road. And then with a mucosal graft, is that what you would use? Actually, there or just not just surgery. So I try to get a synthetic graft in that hole. If you can tuck something in there, soft, synthetic neural graft, if you can get it inside there and then try to rotate mucosa, pedicle mucosa, if you can. The issue is I can't see that whole lateral recess. I don't know how far reaching out. It looks like kind of a small frontal sinus there. But if you could get the mucosa out adequately, maybe get your angled 70 degree drill up out there, you might be able to clean that out a little bit enough to get a neural graft up inside and be able to leave it without trapping the sinus. That's tricky, though. I don't think there's a simple answer. I'd have to really study those films quite a bit more. Juan? Yeah, these are tricky because they are too high a lateral for an easy nasolaxis. So I've done this before actually combining. So first, the classic way of solving this problem is with a lynching incision, right? Just the problem with that is you put an incision in the face and that can have some cosmetic issues and you have to play the bone. But I think transorbital works really nice for this also. So I've done this combining unilateral approach, ipsilateral plus what is called a transcurricular approach, like medial transorbital. And it's a beautiful, elegant approach. You just move the eyeball, either with or without plasticity, and you just pop into the posterior wall of the orbit, super medial, let's say, and then you're right on there and you can have access to the whole area and then you can patch it. Usually for this, I would use an inlay graft and then a free mucosal graft on top. Varun? I think, can I just ask you a question? You'd have a hard time getting a pedicle mucosal graft there, I think with that, right? You have to get a few grafts on top. There's really not a great way to do it. Yeah, a septal flap would be difficult to put it there. I think it might reach, but it probably is too much. If you're going to use a septal flap for that, you'd have to use sort of a random, you know, a wide random without a true pedicle graft. Probably you could try to use your turbinate as well. But I'm saying if you're going transorbital, it's got to be sort of a free graft. Sure, yeah. But again, it's a combined. So this was cool because we did endonasal and transorbital at the same time. So to some extent, the endoscope was in the nose and my hands were through the transorbital route. So it was, it worked really well. All right. Varun, any other thoughts? No, you know, I was just going to comment, you know, if you went with a standard cranialization, you know, with a patient with IAH, if you worry about taking a bigger bifrontal, you start, you know, tearing dura and everything like that. You know, if someone has a decent size frontal sinus, you can kind of outline the margins of the frontal sinus and just do a little anterior table osteotomy, do the cranialization, repair the defect. But of course, the downside would be the bicoronal incision. But you could do, you know, a pretty small bony approach. But I do like the idea of the transorbital. I haven't done that personally, but the trajectory makes sense. All right. And this is exactly what was done. It was a transpulperal incision. There's actually a video here. And this is the image guidance during the procedure. You know, the transpulperal, it works, but the problem is you have the nerve, the suborbital nerve on your way. No? No, if you're medial to it, I think. Not sure. So you can do this through, if you go to the coroncula, you don't have an incision in your eye at all. There is no incision whatsoever. Yeah, it's pretty remarkable how much space you get with that one. You're right. You get pretty good, it sounds like there's a tiny little thing, but you actually have decent space to work with that. Yeah. You have a good oculoplastics guy to work with. Yes. Right. So this is amputated. There's a transnasal corridor here as well. And graft. And then packing. Now, were you able to reach out laterally sufficiently and get the rest of the mucosa out of the sinus? You don't trap it? Yeah. In this case, you could get out laterally and scoop out that lateral mucosa and prepare that sinus? Yes. Yes. We were able to. So the next case, and so that was opening pressure 32. The patient was discharging Dymox. Would you shut this patient if she comes out back with an elevated pressure on follow-up, if she's asymptomatic otherwise? So we've looked at that and studied our patients with repairs, whether lateral or anterior cranial base. And if they're in this sort of equipoise where you think you're going to get away with that, and that exact range, I'm not sure about. And we've sort of moved that range up and down on the scale a little bit as we've gotten experience. But if you follow them, you've got to re-tap them because many of these patients can get intracranial hypertension and elevated pressures after you do that repair. And so if you were thinking of hold off, and that was your kind of threshold, you tried Dymox a while, better re-tap them and be careful because often you do the repair when they stop leaking and they'll climb, and we've seen that in over 40% of the patients we've done repairs on. So if you think you get away in the beginning, you may not in the long haul. So that's my advice for them. Yeah, I agree. Usually I am quite conservative with shunts, so I would place them on Dymox, place the patient on Dymox, and then if they leak, if they recur, and with a very high pressure, then I would put a shunt. But I would try medication first. You know, on that scale, we include things like the tonsils, if the tonsils are low and there's, you know, empty cell, and look at other factors, BMI, and there's many other factors. We throw all this on a scale. We've got a little algorithm for it. In fact, we're just writing some of that newer stuff up now. But I think you weigh all those things in and kind of help to guide you whether you need to shunt that patient or not. But just recognize that those are in that mid-range. They're not normal pressures. They're not super high, but in that mid-range, 25 to 30, like that low 30, those patients, once you repair them, about 40% of them are going to climb. So this is a case that was submitted by Dr. Setri. So I'll let him, I'll drive, and then I'll let him present. This is a seven-year-old. She had a history of right-sided esotropia for a few years, but in the last few months, she had progressive vision loss on her right eye. Initially, her pediatric ophthalmologist thought it was a functional vision loss. Ultimately, she presented with headaches, nausea, vomiting, lethargy, which prompted imaging. On exam, she was NLP in the right eye, 20-20, with a dense temporal hemianopsia on the left side. Next slide. So this is a coronal T2 imaging. She's got a supercellular mass with some extension towards the right peripeduncular space. Next slide. This is the post-contrast imaging. The cavernous sinus looks reasonably spared. It doesn't look expanded. And you can see where the position of the A1 is on the bottom left, and it goes up into the third ventricle with some hydrocephalus. Next slide. She had some laboratory work. It was remarkable for mildly elevated prolactin. She also had elevated IGF and GH, but factoring in her age was just barely debatable what the normal limit is. She did have a GH suppression test, which did not suppress at all, despite adequate doubling of the glucose. But she did not have any features of gigantism. Next slide. Is the IGF1 within normal limits in that range? It's just, at that age, it's a little bit debatable, but the endocrinologist felt it was mildly high. OK. So, you know, I think for debate here is, you know, what would be the best way to approach this, you know, transcranial versus endoscopic and the nasal, and or if you want to do both, you know, which way would you go at it? So maybe I'll start with Juan. Can you go back to imaging, please? It's a tough case. Unusual, you know, seven-year-old with a large tumor that is like the pituitary tumor, but I guess it could be something else. You don't have an axial, do you? No, I don't. I wanted to understand how the tumor is going lateral, you know, because sometimes you have one single picture and the tumor goes lateral and say, I cannot get endonasal, but maybe there is a corridor to bring the tumor down. I just don't know from the imaging. Got it. Yeah, the only thing I would say is that, you know, it's not going through the roof of the cavernous. It's kind of encasing around the ICA, going above and below the ICA lateral. Yeah. No calcifications, Arun? No calcifications. Good question. Yeah. As a general principle, you know, when I have to deal with a large complex multilobulated adenoma, I always worry about leaving tumor behind that can bleed in the post-op period, right? I think with all experience that I've had, I've seen a lot of experience that or seen that and it can be nasty. So I think it would go endonasal, trying to get a full resection, but be prepared to do a craniotomy at the same time. If I'm feeling that I'm not reaching what I need to reach, then it could be just simply an eyebrow or it could be, you know, your standard terianal or OC approach. Okay. And, but your preference would be first endonasal, if the patient did not have any, you know, post-op ischemia, hemorrhage, you know, kind of thing, then come back with a craniotomy if needed for the residual. Yeah. My plan would be to achieve as near a complete resection as possible with the endonasal. I'm not planning for a second stage. And if I think I'm leaving a significant residual in the same setting, I will go open. Got it. Okay. Got it. And Jim, any thoughts? So I'm not a big fan of combining when I can avoid it open and endoscopic. I think that opens risk of infection and other problems and kind of compound things that you can avoid. I know that you get your hand forced sometimes, Juan. I've tried all those things over the years too, cranios, et cetera, and had, you know, combined. And so another thought is this whole concept of what you do first, if you think you need two of these, two approaches, meaning a transcranial or sort of above and an endonasal from below. And it depends upon how much I can get out. If there was a huge component, I showed a couple of slides of those giant ones, this huge component that's out in the middle left field. And I think there's going to be a large residual that I'm probably going to truncate. It's a venous outflow, et cetera. Maybe it may infarct. Then I would rather to go by transcranial first. Otherwise I would always rather do endonasal first and try to take away blood supply coming into this thing. You can usually get a lot done endonasal. If you come upon some really firm fibers, you think you're going to battle and get some portion of it out and yet still be faced with a big piece that's left into cranially, you might stop early endonasal and come back transcranial, not push your luck. But this looks like, you know, again, I kind of agree with Juan. I'd like to see the axial to see like, what's my window? Is this a really narrow thing that it invade through? Is it, is it some big, you know, a portion that I'm not going to have access to a very narrow window, or maybe as I decompress it, I'm going to get to deliver this tumor in a little bit. The other thing is staging this. So you may try to do, and I think I would, as much as I could endonasal, get a feel for the tumor. If it's soft, kind of work my way through it and, you know, figure out what it is. I'm pretty sure that's a big pituitary tumor as well. And then if there's a residuum, it may collapse, right? And I've done this kind of thing either volitionally or because I got my hand forced and done a staged endonasal approach. And that lends itself into all these different repairs and how you might manage that. I wish I could show you some, some examples of that. But so I would, I would, I think I agree. I would, I would try endonasal for this. I think the component that you're not going to reach is probably the minority of this. It lends itself well with what's in the third ventricle in a lot of areas. I think I would shoot for that first and see what I could accomplish, recognize you may need to come back. The other thing is those ventricles are pretty dilated, just heads up on that. It looks like some hydrocephalus going on. You may battle that going up to the nose. So you need to be ready to manage that as well. That patient's got obstruction. You'll probably relieve some of that, but just heads up. Yeah. Yeah. I should have added that she ended up requiring an EVD on admission. So we can go to the next slide. So for her case, I ended up wanting to stage it. I didn't feel I could get all of it endonasal or transcranially. And just kind of my own bias is not to do them both at the same time. And I don't have hard evidence for this, but kind of my general rule is if I can't get out 90% of the tumor from below, I worry about the blood supply starts from the cell and grows up with the tumor that I kind of undercut it. So I don't know if the risk is higher of ischemia starting with below versus from top. But anyway, so we did a right OZ. We removed all the tumor except the cellar portion, and there was a small capsule that was remnant on the anterior choroidal branches. You can see it on the post-op MRI, but a little subtle thing we saw in surgery. So her EVD was weaned and removed. Next slide. So that's kind of the remnant here in the cellar, and we planned for kind of a simple transcellar second stage. Interestingly, essentially, the pathologist called me and said that this is pituitary cancer, aside from the fact that there was no metastasis, so they couldn't call it a pituitary carcinoma, but had a KI index of 40% with some prolactin and GH staining. Next slide. Some of her markers came down, even though there was residual tumor. Next slide. And then, so we planned for, you can go back one, just in interest of time, we did our second stage. One of the debates that came up with the oncologist is the little bit of gland there, do we preserve that or do we resect that, given that it's a high-grade neuroendocrine tumor? In the end, in interest of time, I ended up, they basically told me to resect the gland. And actually, when we sent the gland separately, there was infiltrating tumor in the gland. Next slide. Yeah. So that was the end result. There was also a discussion, do we now treat her with adjuvant radiation or not? And after tumor board discussion, it favored adjuvant proton beam, so she, you can go next slide, she underwent proton beam and she's been disease-free for four years, but obviously under surveillance, panhypopit as expected. Yeah, close surveillance, right? That plays a role, as far as resecting the gland, I was going to kind of mention that as you were saying it, that if you're going to end up using adjuvant radiotherapy, you're probably going to, might as well take the gland out. It's not going to survive that dose anyway. It's a young kid. I would take it out and go for it. That's tricky. Did you find it was very fibrous up above? Were you happy it went from above first? And obviously you did a great combination, Brun. Yeah, I would not call it fibrous. It was kind of... You think that lateral part would have delivered in from endonasal? I don't know. You kind of learn as you watch, you don't think so? Yeah, no, it was actually very stuck to the PCOM and anterior choroidal branches, so definitely wouldn't have been able to dissect that off endonasally. I had a philosophy for a while. I'm not sure if this is something you and I spoke about back when you were here, but of this concept of when you have to go above and below, say it's a 50-50 thing and not one of these that's mostly above and you clearly choose to go from above or mostly below and you clearly choose from below. When they're 50-50, my philosophy was just like yours. And again, I don't know if that's something that we talked about or you came upon, but I would go from above too first because I was always worried about that, you know, cutting off blood supply, leaving something in there that might infarct. And I'm not sure that held up over time. I'll admit that I've gone more toward endonasal now and been more aggressive with it. And I haven't seen those catastrophic problems. But my general philosophy is the same exact thing. You have to do both, go from above first, get that out, and then deal with the bottom separately. And you're a little bit more likely to kind of manage that kind of bleeding and things like that and avoid some hemorrhage in the brain, but I'm not sure it pans out either. Yeah. Yeah, I did have one case. Well done. I think, you know, you did the right thing. I mean, in the sense that if you don't think you can get endonasal more than 90%, you should go open. There is no question about that. So well done. Yeah, I was going to mention, I had one case of another giant, right? I kind of did a similar technique. 48 hours post-op, he developed a ophthalmoplegia. I repeated a scan and basically the cellar part, you know, became ischemic. So took him, you know, to surgery and obviously it was basically a necrotic tumor in the cellar, so. Adding to the muddy waters of which to do first. It goes both ways. There you go. But that's easy to handle, right? So that's easy to handle then. Super easy and he recovered, yeah. Yeah, right. That's a good point Juan. You know, that's much easier to manage. Maybe if you get stuck doing that late at night or when you're on your heels. Yeah, that's true. Nice job Varun. And this is the final case to close up the day. It's a case of mine. It's a 64 year old man. He had a known supercellar mass and presented now, this was followed slash he was lost to follow up. And presented with bitemporal hemianopsia. The MRI, which will show that the mass had progressed over the last eight years. Largely normal lab work other than a slightly elevated prolactin. This is the MRI of the patient. You see it starts down low. Was in the pre-pontine cistern. I'll show you the sagittal as well. And extends a little bit into the fissure, not too much. And a little bit in the third ventricle as well. And please have me scroll back and forth if you'd like me to. This is how the tumor looks like. And I'll show you a T2, but it does look, if you window it appropriately, it looks separate from the actual gland. The gland looks, it's a separate entity there. And it did look more like a separate entity even on the prior scan. I apologize, I didn't include it. I can come back to this as well. This is a coronal T2. And this will show you even better. There's a high-riding basilar there and this is running through it, et cetera. But you see here, like in the suprasolar cistern, it looks, this is a gland and this is the mass. I included a CTA as well. There's no calcifications that are obvious here. Again, he's in his 60s. So a little bit less likely to be the age range of calcifications, but they're always possible. So I guess at this point, what do you think is going on? Obviously it's been a slow growing process. He is symptomatic, likely he needs surgery, but what do you think the diagnosis is and what would be potentially your approach? I guess we'll start with Dr. Evans. So I think it does look somewhat distinct from the gland, the best I can tell, that's what I was thinking. I'm trying to sort out how distinct it is from the chiasm. That looks like it's pretty distinct from the chiasm as well. Like it's elevated. I don't think it's necessarily involving the pathology. We always have to consider that. Certainly like meningioma, diaphragm meningioma comes to mind with a gland that's pushed down and kind of displaced downward. You've got a bit of a tail, looks like draping down below on some of the sagittal cuts as well. I think that's gotta be somewhere, certainly in our differential, maybe larger differential. I don't know what the poster gland looks like. And you've got a lot of tumors in here that can be troubling, right? Granulose cell tumors and chrosome, et cetera, that can be very difficult to take out sometimes. So it looks, at least it looks like it's separate from the adenohypothesis. I don't know about the poster gland per se. I don't see what the infundibulum is. Can you show us the infundibulum at all? He didn't have a DI of note. He didn't present with anything like that. Okay. The infundibulum is a little bit hard to follow. Hard to see, right? Hard to kind of identify it on that. A little bit hard to follow on the axial. So I guess we could continue our differential and get kind of out there a little further for other kinds of tumors. It looks like this has been slow for a number of years. Malignancies get a little lower in the list, but certainly it's gotta be somewhere. It was that bright on T2? It was a little bit bright. ISO too bright. And the bone's not too eroded. I think it was expanded more so. Not really eroded. I'll show you the CTAs as well. I mean, it's not. No clear infiltration of the bone there. You see that? Yeah, not drastic, right? Yeah, and the cell is not expanded, right? Cell is not expanded, correct. But it's still getting adenoma, but it would be an unusual looking adenoma. Yeah. Not the typical one. I think I will go with your meningioma diagnosis, Jim. I think so too. Or this could be a diaphragmatic or posterior clinoid or some cell meningioma kind of thing. Or distal ring meningioma, as we call it the two. Yeah, diaphragm seems a little less likely to drape down your clivus like that, but it does. It can, just, I think that's probably reasonable. In terms of approach, would you do anything different? I guess, what considerations would you take if when you tackle this? Well, in terms of your approach. I guess- How old's the patient? He's 63. Also, it bothers me a bit. I don't see dural tail clearly. I don't see heparostosis. I am not sure this is meningioma though. So yeah, it's a bit atypical. Anyone think it's a cranio? I think that's got to be somewhere on the list. It's possible, but it wouldn't be my first choice, but I think it's got to be on the list. You've got a supercellar mass that your gland is kind of sitting below. I think it's got to be somewhere on there. I can't see an infundibulum. I mean, I don't think you can say no to that. It doesn't have to come with DI and everything. So that's possible. I thought it had a bit of a tail going down the clivus on that sag, though, that sagittal contrast, no? I would say- It would have been useful, yours, to see the initial scan eight years ago to understand a bit better what is this. Oh, yeah. How was this, you know, eight years ago, right? Yeah, and I do apologize. I should have included it, but it looked like this, but smaller. There is another important point, which is you see the third ventricle, it's pushed up, meaning this thing is not coming from the hypothalamus. If anything, it could be coming from the stock, but not from the hypothalamus. The third ventricle is pushed up. So that rules out some pathology. I think, you know, you also have to, I guess, think of the goals of surgery, right? I mean, it's got a bi-temp. The two things I think you need out of this, if you had to just pick one to help his vision, maybe one is to get a tissue diagnosis in this case, but to help his vision is high on that list. And then depending what you come upon, it's consistency, et cetera, is try to get it decompressed. It's clearly not going like wildfire if it was a little smaller and it was there eight years ago. But I think that's sort of the goals. And I think endonasal is the way I would tackle that. Any questions in terms of the approach? In terms of your endonasal approach, would you, I guess what, how would you go around doing this? Would you just get a biopsy first? Would you just do all the exposure for doing everything? You want me to answer that? Yeah, I guess. Yeah, I would prepare to do everything. So I would take down, and the bone's probably gonna be largely thinned out anyway, right? The cell, et cetera, is probably thin. I mean, I can't tell, it looks like sort of that tumor in the cell right there, but I'm gonna assume it's kind of thin, probably at the tuberculum cell and up at the plenum as well. And so I would prepare to do something more open. I would expose. I think you don't have to have a huge dural opening. You can make a small dural opening and get a piece of that and find out what's going on. Are you gonna get it handed to you? Or is it gonna be something you can manage? And then I would just sort of methodically work through it. I think, obviously, you'd want to preserve your nasoceptal flap and immobilize or not. That's another area of debate, but have it prepared and preserved on both sides. You could mobilize if you need. You got a huge sphenoid to work in, which is kind of nice. I think it lends itself well, again, to this endonasal approach, but I would have things ready to kind of forge on to do the operation with those things in goal. Again, tissue diagnosis, decompress the chiasm, and then go on with removal if it seems it's gonna be safe and feasible. Varun, anything different? Just a couple of comments. I would say, I was curious to see if on the intrinsic T1, was there any hyperintensity, which would suggest cranial, but otherwise I totally agree with meningioma highest on the list. And I would expose the tuberculum sella and underneath take down the floor and the superior clivus to have the exposure. But then the same thing with Jim, go tackle first, decompress the chiasm, clear everything from the optic nerves down to the gland. And now once you have an open window and you know your diagnosis, then see if you can elevate the gland to come underneath for the rest, depending on the diagnosis and what you feel that your goals are at that time. All right. I agree. Can you go George on the axial? So you definitely need the pituitary transposition, right? To get to the tumor that is on the dorsum sella? Well, it depends. I mean, yes, but I guess some people can tackle it differently. Yes. Some people can't. So there are different ways of doing that, right? So. There are different ways of doing that. I'm with you and that's what I did. I'll show you. But I mean, there are definitely ways, I mean, depending what the tumor gives you as we're saying, if it's soft, like it was. Sometimes a simple hemitransposition is all you need. You know, just go on one side and move the gland to one side. If you want to go to that ipsilateral side and that's all you need. Right. So not to belabor the point, I know everyone is tired, but that's exactly what I was thinking as well. And as Juan was saying, I was prepared to do a hemitransposition to expose the upper clavus. Dividing actually the upper clavus there and removing some parts of it. And I started doing the transposition or the interdural posterior clinoidectomy in preparation for the transposition, dividing the ligament disease that corroded here, scalenized and removing the posterior clinoid. And then before I did any more, I wanted to get a diagnosis. And this ended up being a pituitary adenoma. Mm-hmm, mm-hmm. I started dividing and then got into it. It's very, very soft, very, very workable. You can see the stalk actually here. Yeah. Not to surprise, I've seen adenomas just like this. Right. There can be anything adenomas. Right. So it seemed to have started from like an accessory pituitary gland. I'll show you later. I'm looking for six here and make sure that I can come around. But this hemipresposition really helps sort of get a very good exposure and a handle on things. These are very high riding. Interestingly, basilar artery is a PCOM that's actually going up. Way up, yeah, way up. So- The infundibulin looks a lot more obvious there. Right here, the infundibulin looks much more clear. This tumor going into the proximal sylvean fissure, that actually, because it was soft, it was better lucky than good, delivered nicely from the sylvean fissure. And then that part that was heading into the third ventricle, I was partially infiltrating the third ventricle. I opened just a little bit just to make sure. And then- You know, the key in a case like this is to be so good controlling your suction strength. Right. If you just let it go, you're going to start sucking perforated branches. Right. You have to be so delicate with that. Right, exactly. The other thing I would say, Jorge, is that I think you prepared, you did a transcavernous kinectomy thinking it was a meningioma, perhaps. I'm just thinking- I did not know. I did not know. You're absolutely right. Right. Because knowing this is maybe an adenoma, I would have done intradural transposition, meaning I would have opened the dura, see the pituitary, move the pituitary, and then I don't have to open the cavernous sinus. Well, interestingly though, just because it looks so different, I'm kind of glad that I didn't do that because you'll see, and there's some pictures here, the actual pituitary gland was normally, well, I actually opened it to see if there was something that was missing. And this was all normal pituitary glands. So preserving that venous outflow, I don't think it was actually a mistake. I mean, you can argue to remove that, but I think that venous outflow on the covering, as you've taught me, I think it was actually beneficial to have. And then just looking around with the angle endoscope in the end is, again, the part that was going out towards the fissure that was cleaned out. So again, because it's a soft tumor, it was easy to handle. Better lucky than good. Very nice. It was just a non-functional pituitary adenoma. And he did quite well. His vision improved near normal even before he left. There's no evidence how pituitary has been preserved. Now, Dr. Evans saying this, you can see actually now the stalk now there that separates a little bit more nicely from the tumor. I think I would have started with that supercellar to the center of the tumor where I could get tissue and really address the chiasm. Another idea is... I think he's frozen. But this shows, you know, I think some studies might have recommended a combined transpetrosal or something for this case because of the- Maybe that gland is still- Dr. Evans? Yeah. For a minute, if you can restart one more time. Yeah, we lost you for a second and we didn't- Oh, sorry about that. Yeah, so one thing you could consider, I would have started supercellar, I think in that case, to address the two things we wanted to accomplish. There's the goals of surgery or tissue, find out what it is, and two, to decompress the chiasm. You may be able to actually work. If you have enough space, you had a pretty big space to work in, it seems, in the sphenoid. But another way you can do that is just work below the gland. I mean, you could just go transclival and you can work above and below without having to mobilize the gland at all. If you needed to reach down, if you found this was a tumor you really had to be aggressive with going down low, granted, it's been eight years and it hadn't grown like crazy, so it's probably not a real aggressive tumor. I think the disadvantage of doing that is you have a bigger opening down below to repair, but you've got a pretty big opening with the transposition as well. And you might be able to just work above and below the gland. You can sort of effectively do that without the need to mobilize the gland or take it all down. If there's not pathology in the cavernous sinus or some reason, like a meningioma, you've really got to mobilize the gland to get back to the posterior clinoid. Just a thought, but you can maybe work above and below as well. You're absolutely right. I mean, and Juan is right that going in, I was thinking more that this is more likely a meningioma or anything. And then the reason I went transcavernous is that there's also partly to devascularize it as much as they could, as we were waiting and everything else, as we were working supercellularly to give it time to sort of, you know how if you devascularize a meningioma over time, it sort of just becomes more workable. So to give it like that, but there's definitely more than one ways of doing this. That's a great, great, great outcome there. And no problem with leaks, repair was okay? Yes, I mean, I didn't show it, but we used a fascia latae inlay, an inlaid to a matrix, I have it here. You know, George, over the years they've asked me, how do you choose which pituitary transposition to do? And you widely classify them in intradural and inter or extradural to the cavernous sinus. I say, it depends on the pathology. If it's extra axial pathology, let's say meningioma, chordoma, conus sarcoma, I go to the cavernous sinus. If in general, okay? If it's intradural like adenoma or craniophorene myoma, I go intradural transposition. And simply because if it's intradural, you want to see the pituitary gland tissue and you want to see the stock. If it's extradural, you don't want to see that. You don't need to see the pituitary gland, right? Yeah, absolutely right. So with this, I guess we'll round up with a couple of questions and then we'll call it a day. I know it's been a long day for everyone. This is the end of a long day, I'm sure. So I guess one for Dr. Fernandez, do you always resect the media wall in functional tumors that abut the media wall of the cavernous? The answer is no, because if they just abut the wall and I can separate the tumor from the wall and I have a nice pristine wall that I don't think is embedded, then I don't remove it. Maybe I just touch it with a bipolar, yes. I don't know why, but because I can, that's it. But if it's clearly embedded and I can see that there is no clean plane of separation and I think it's embedded, then I'll take it. It depends on all in the interpretive assessment. Okay, so you base it on how it looks like during surgery, not the rest of it. If it's a growth hormone, I know that abuts it and then it's high rate of involvement you don't always take. So- Not always, I mean, especially if it's a grade zero or one, I know some of them are non-embedding, but I have a very low threshold. So it has to be such a clean resection that I say, I mean, how am I gonna remove this wall if it looks so clean? Then I don't remove it. Right, I guess a last question for Dr. Evans for using the button reconstruction. Have you ever had any issues when going back? As far as reopening a button? I guess, yes. It lends itself pretty well, actually. It hasn't been too many times we've had to reoperate on them. That'd be an interesting little series to look at. There's probably not too, too many, but no, I haven't had any big problems with it. It can scar in place pretty well, but you can open it just like Dura. It's like having two layers of Dura basically. And so classic thing would be like a craniofringoma that recurs. You can actually go in and either peel that down or just resect it right in the center. And we've done this so-called button and button repair afterward. And that actually works reasonably well. And so, no, I don't think it's a major problem with like too good a healing or too scarring or too scarred or that kind of thing. It actually opens pretty well. All right. Well, again, I know it's been a long day for everyone. I'd really like to thank everyone again, both Juan and Jim for being here and sharing their wisdom and fantastic presentations. I think this is gonna be a fantastic repository for everyone. And it's gonna stay on the website for anyone to access again at their leisure. I'd like to thank everyone, Vroon today, as well as Shannon and Sam for all their hard work getting this together. And we'll see you again soon for another episode. Thanks so much. It's a great evening. You guys are great hosts. I really enjoyed it. Thank you, guys. I must say, Jim, it's great to see you. You might not remember, Jim, you look the same. And then when I first met you in 2005 or six, I don't know, five, I was in Rodman's lab and you came as an already invited guest. And you saw me for the first time, those beautiful Indonesian approaches. You were already doing them at that time, 2005, 2006. I was so impressed. I stick to you by your side, trying to learn everything I could from you. So thanks for all your mastery and friendship over the years. Thank you, Juan. That's great. It was great to meet you then. It's been a great long number of years with friends and colleagues with you. So thanks so much for saying that, Juan. I remember those days very well and very fondly. Yeah. Thank you, guys. And also, let me say, we are so proud of you, Varun and George. You are the young, I don't consider myself young anymore, but you are the rising stars in the field and you guys need to do better than we are doing. So go for it. Thank you so much. Thank you, guys. Thanks, guys. Have a good night. Have a good night. Bye-bye. Have a good night, everyone.

skull base surgeries

pituitary surgeries

anatomical counseling

endoscopes

reconstructive techniques

microdannomas

macrodannomas

acromegaly

cavernous sinus

superior hypophalamic aneurysm

endovascular treatment

frontal sinus defect

obstructive sleep apnea

tissue diagnosis

suprasellar mass

neurosurgery