Aaron, if you'll stay up here. I'd like to introduce Dr. Shankar from the University, excuse me, the Medical College of Wisconsin, who will be presenting the CounterPoint presentation on ultrasound imaging. Thank you to the organizers for inviting me, especially Mark. And it was interesting to listen to the talks by previous speakers, including the client lecturer. I don't know whether I really need to talk anything more about the use of ultrasound because they have exhaustively covered. That's what you expect from brain surgeons, right? And what is an anesthesiologist doing in this crowd? So I was a little bit concerned about talking to brain surgeons or neurosurgeons. I have no conflicts of interest. And so I didn't want to feel like a fish out of water. And I brought this clip of an ultrasound image of a goldfish in a tank. So I'd like to remain in the tank. Anyway, as you all know, ultrasound can be used as a therapeutic modality. You may have heard about the high-fuel, high-intensity focused ultrasound. The other one is diagnostic imaging, which most radiologists use and do. And the final one is the imaging guidance, which is what I would like to talk more about. The Fry brothers from Illinois were one of the earliest to develop the high-fuel system. And I would like to pay homage to them. Russell Myers, one of your senior members, who is no more, unfortunately, he did the first high-fuel lesion in neurosurgery. And that's why I thought I'd bring the connection back to ultrasound, my talk, and ANS. So what is the advantage? The major advantages of ultrasound is that you can see. You can pretty much see and not believe. You can see the target. You can see the needle or scalpel or probe or any other instrument that you want to put in. You're going to have a narrow keyhole for you to introduce whatever you're trying to introduce. You can either inject, lesion, cut. I don't think we are far enough advanced to do suturing yet. One of the things from Peripheral Nerve Surgery Operative Exposure's book, if you think it's the nerve, it's probably not, which I'm sure most trainees are much more familiar with these three sentences. What I would like to add here is, even at the end of the case, you will still be able to see the nerve with ultrasound because you can use it on the field. Alright, let's talk about detecting the target. Now, there was a lot of talk about neuromas, brachial plexus avulsion injuries, various types of nerve tumors around the brachial plexus. And here you can see how clearly it is separating. This is the nerve L5 nerve root coming out and it's separating into the scapular nerve, suprascapular nerve and so on. And this is a normal individual. In somebody who has a neuroma or a tumor, you can easily detect that with ultrasound. In the bedside or in your clinic. And even in the operative field, it will help you to plan your incision. So what about the different structures in the upper limb? You have the brachial plexus at the intrascalene groove and you have the capillary nerve. You can see the fascicles inside. This brings up the point of trying to slice through the neuroma or any type of injury and finding out where the fascicles actually start. So if you actually trace the nerve, you may be able to detect where the fascicles are starting or ending. And that would help your neurosurgical planning. This is your carpal tunnel in four different views. And you always want to check with a color Doppler just to make sure that you don't have any vascularity in that particular area. What about lesioning? Being an anesthesiologist and a pain doc, I'm more used to the RFA needles and whatnot. So if you can identify a neuroma, you know where to put the incision. But in my case, what I do is I block proximally and put an RF needle to kind of burn that neuroma, destroy it. But of course, you guys have the capability of actually using your sharp knives to cut through here and suture or re-suture or re-anesthemose. This is one potential use. What about stimulation? Some of you may be interested in peripheral nerve stimulation and these days we have wireless stimulation where you can actually put the electrode very close to your nerve or target. In this particular case, it's for the shoulder. They were targeting the axillary nerve. So you can actually specifically locate it there. This is a real-time placement of a target of a stimulator lead right close to the sciatic nerve. It's about one and a half to two centimeters away from the sciatic nerve. And once again, I want to point to you the fascicles that you can see in the sciatic nerve. This is going to help you to plan your surgery as well as understand what is actually causing the problem. Now what about the surgical challenges of peripheral nerve stimulation? Some people have difficulty with the tunneling. Lead tethering, migrations, lengthy operating times. But once we started using ultrasound, I want to say it's getting much, much shorter. So if you were to look at the stimulator and the generator leads, this is how the top of your this is how the top of your IPG is going to look like. It doesn't matter at all. The only indication or only situation where it's going to be useful is when you have some type of a suspicion that there is a fluid collection like a seroma or even if there is an abscess on top of it, you could target that specifically and remove whatever is there. The next thing is you can see the IPG lead insertion site and you can trace the leads subcutaneously all the way down to the periphery. This is coming down and then up here. So you are able to trace, track these stimulator leads and detect any pathology in that particular location if there is a suspicion for it. Now, so we know that tunneling to the IPG is feasible. You can detect lead tethering or migrations, possible, maybe. High-end resolution ultrasound machines. And lengthy operating times, maybe we will decrease because we already plan what we are going to do. So the major advantage is to summarize. I don't want to talk about other stuff, but the most important one is the real-time bedside interventions. You can detect pathology in the target area and avoid structures like pleura and vessels. Of course, when you are operating, you can definitely avoid them. But still, if you are using an endoscope or a smaller needle-guided approach, this is probably a good idea. Resolution, probably I can only say it's good compared to mammography. But it's sufficient. These days, you do get machines. If you go for the higher-end machines, it's probably going to be 300,000 like Dr. Fuller was talking about. But the pictures that I took were all from $50,000 machines. And they are new, brand new. So if I can do it, I'm sure you all can do it. There is always a learning curve. You need to know about the hand- needle coordination and a good understanding of anatomy, which you all do have. So this is probably the only major hindrance for some of us old folks like me, but the youngsters should be able to pick up on this one. Limitations, patient tissue contrast, radius between individuals. As the muscle atrophies, it all becomes very bright. And of course, you can't visualize anything under bone or air. And with that, I conclude my talk. I actually brought a gift for Dr. Fuller, hoping that he won't be very mean on me. And this is a brownie. Thank you. Aaron, do you have any comments? One area I didn't talk much about is the interventional injections, which is an area I've put a lot of time into, and particularly with regard to thoracic outlet syndromes, proximal brachial plexus entrapments. One thing I've done a lot with is the use of high uronidase to accomplish decompression of nerve entrapments by MRI. So you can go up to the, march up to the needle edge, a little hydro dissection, put in some high uronidase, and large, I find a large fraction of the TOS, perhaps, or disputed, whatever, pain patients will improve, often very significantly. And this is kind of a real-time MRI issue. So, and I think that that's, you know, certainly an area where the ultrasound and the MRI come close together, where you're trying to essentially guide injections and get close to a nerve. And there, though, I think that the big advantages are that it's the standoff technique of the MRI versus having to keep, you can have your probe in the field with fluid, and you're trying, how do you, you have to put a needle through the gel into the surface. That, I think, gets to be a real limitation. So there are two interesting things that I want to talk about. One study that I'm currently working on is I don't need gel to place a transducer on your target. Any fluid is enough. Even your normal saline is good enough. I use ChlorPrep for the skin and also as a gel, which means that I hardly ever use gel at all these days. The other interesting thing about it is MRI has a very definite role. All that I'm begging and pleading is ultrasound also has some role. It is like embracing all the modalities available so that we can offer better patient care. If the MRI suit is booked, I don't have to wait for them to make a diagnosis. I can always have a suspicion. I think it is more about embracing a new technology, embracing a new imaging modality, that is where ultrasound comes in, and that's where I was going to fight for. I think they each have their role, and I appreciate very much your very nice imaging. Thank you.

ultrasound imaging

diagnostic imaging

imaging guidance

detecting pathology

nerve tumors