I'm really happy and proud to present a friend of mine, Dr. Ugur Ture, whom I knew 24 years ago on the ninth floor of UAMS. There were three young poor neurosurgeons working together, Dr. Luis Borba from Brazil, Dr. Ture, and myself. And we fought together. We fought among ourselves, first of all, and then fought with other people. And last year in Istanbul, I was so proud and my heart was full when you organized one of the best meetings I attended for a long time. And you became the president of Turkish society, and Borba became the president of Brazilian society, and I'm the only loser who hasn't been the president of national society. Ugur, take the podium, please. Thank you, Mr. Chairman, dear colleagues. It's a great honor for me to participate in this special symposium. Thank you for the invitation. Everyone can tell who is the loser, so don't worry. Everyone knows. You did a great, great success. Thank you, Kenan. And I will talk about the thalamus experience, my surgical experience with thalamus. Thalamus is a Greek word, ancient Greek word, and first time Galen of Pergamon used this term. It means that the inner chamber, most inner chamber of the Greek houses. It looks like a bedroom of the married couple, so it is the most deep part of the house. So this is the real deep lesions. It is commonly regarded as the gateway for all inputs directed to telencephalon, and it plays an important role for somatic, vegetative, and cognitive functions. And it may be speculated that the little knowledge of the region and difficult to reach with the surgical approaches are responsible for the conservative attitude generally shown in the neurosurgical community toward thalamic surgery. And main syndromes in thalamic lesions are raised intracranial pressure, motor deficits, sensory syndromes, involuntary movements, and seizures. And these are real deep seated lesions, but majority of these lesions are focal at diagnosis and amenable for surgical resection. But the surgical treatment is still challenging because of the deep location, vascular supply location, and also the CSF pathway. Interoperative ultrasound and MRI is available, but the problem in most of the cases, I use semi-sitting position or lateral position, which I cannot use interoperative MRI. Interoperative neurophysiological monitoring is also helpful. The thalamus, the lateral side of thalamus, is covered by very valuable white matter. This is, in my study, there are seven main fiber system in the lateral side of the thalamus. In the coronal picture also you can see the lateral side of the thalamus. So, forget it to use this pathway. So, we should not go to thalamus from lateral side. We should not go to the thalamus from the cortex and white matter. So, we have to find out how we can reach the thalamus from medial and superior. This is our study, show that there are four surgical surfaces to reach the thalamus. First of all, lateral ventricular surface, this color. Velar surface, which if we open the coroidal fissure, if we mobilize the fornix, we have velar surface. We have cisternal surface, or here. And then we have third ventricular surface. So, I would like to demonstrate some samples for my surgical strategy to get the thalamus. And I never use the lateral approaches. You can find detailed information about this classification in our recent publication. Surgical approach I use for thalamus, mainly three approaches. Anterior inter-hemispheric approaches. Posterior inter-hemispheric paracitlenial approaches, but not transcallosal. And infratentorial supracerebellar. So, the only anterior inter-hemispheric approach, you have to sacrifice some neural tissue. You have to do callosal incision. But other two approaches, we do not need any incision in neural or vascular structures. Anterior transcallosal approach is useful for superior and anterior lesions. Especially if the tumor protrudes in the lateral ventricle. And no disruption of hemispheric tissue or cortical tissue. No cortical incision. Just small callosal incision is enough to reach the thalamus using anterior transcallosal approach. And one advantage of this approach is always, you know where is the corona radiata. So, you have your lateral limit when you start surgery. And you have orientation in the thalamus. And this here is the lateral ventricular surface. This is one sample. Because of acute hydrocephalus, they put external ventricular drainage in another institution. And this is left. Left is left always in my pictures. Left thalamic tumor. And typically obstructing aqueduct. And this is the reason he had the acute hydrocephalus. And we choose anterior transcallosal approach for this case. Also sensory and motor fibers you see just pushed laterally. The thalamic tumors never invade the pyramidal tractus. And if we choose anterior transcallosal approach, we have our lateral limit in the surgery. So, we use lateral ventricular surface. I always use right-sided cranotomy, but I go to left thalamus. And the beauty of this approach, you can perform third ventriculostomy same time. So, it can preserve the postoperative hydrocephalus. So, this is the left ventricle. And this is my incision, my resection cavity here. This is left foramen of Monroe. And this is the incision in the left thalamic ventricular surface to remove the thalamic tumor. And this is postoperative picture. And radical resection of the tumor with the transcallosal approach. And this is normal sensory and motor fibers. I promised Kenan to be on time, so I... You have time. Okay. And it was globalistoma. Another case, it is large tumor, but it is still thalamus. And it never invade the internal capsule. But it goes down, pushed up, downward, up to the colliculus. But still, this is thalamus tumor. Still thalamus tumor. And... But it's herniated. It goes down. But this is still thalamic tissue. And the sensory and motor fibers are still intact and pushed laterally. And in this case, I use, again, anterior transcallosal approach. My incision is lateral ventricular surface, but I involve with all the surfaces of this tumor. And this is postoperative picture using anterior transcallosal approach. Again, I go right-sided anterior transcallosal incision, but go to left thalamus. And this is after resection. And sensory and motor fibers are intact. And this was grade II, grade III astrocytoma. Another approach is posterior inter-hemispheric parasplenial approach. I never cut the splenium. But under the splenium, you can reach the pulmonary. And without any incision. And preservation of optic radiation is advantage. And large region in the parasplenial area, you can reach. And cisternal surface of thalamus, you can reach very well with posterior inter-hemispheric parasplenial approach. And this is one of the lesion, left-sided thalamic tumor. Left-sided thalamic tumor. So this is excellent case to come from here under the splenium to remove this tumor. Again, sensory and motor fibers always push laterally. And I use posterior inter-hemispheric approach in lateral position. And this is, you see, the splenium is here. And when you open the cistern, and you have tumor here. Because the pulmonary thalamic tumor came out the surface almost. So this is not any more deep lesion. So just internal debulking of the tumor, resection of the tumor. And this is after resection, endoscopic view. This is splenium here. And galenic venous system here. And this is the resection cavity. This is right thalamus. This is third ventricle here. So we have also nice orientation with this case. Low-grade tumors are more difficult. Because thalamus tissue looks like low-grade tumor, to be honest with you. And this is after resection. Again, left-sided thalamic tumor, pulmonary thalamus tumor. But I use posterior inter-hemispheric approach in lateral position to come here. And to get the pulmonary thalamus without any cortical or white matter incision. And it was grade III astrocytoma. Another approach, which is one of my favorite approach, paramedian supracerebellar transtentorial approach. This is completely extraxial and less invasive. But limitation is if the tumor extends laterally, it's difficult to reach this approach. But if the tumor is mostly underneath the splenium, I prefer this approach in semi-sitting position. And this is one of the samples. Again, left-sided medial thalamus pulmonary thalamus tumor. But you see, I cannot use posterior inter-hemispheric approach. Because the old tumor is underneath the splenium. So I have to come from here to remove this tumor. So I use paramedian supracerebellar transtentorial approach. Excellent for the cisternal surfaces of the thalamus. And here, to come from here directly, you have the thalamus in front of you. And it's not deep anymore. This is after resection, coming from paramedian supracerebellar. And in removing medial pulmonary tumor. And this is also normal. And it was grade II astrocytoma. I show samples of gliomas. The cavernomas are much more easier. So this is the reason I put all gliomas. And this is another interesting case. I have three cases like this. Totally third ventricular surface. This is third ventricular surface of the thalamus. And it's not easy to reach. And if you come from above, you can damage the normal thalamus. And for me, this is the excellent case to go. Contralateral supracerebellar transtentorial from here to here. This is again. This is third ventricular surface. This is third ventricular surface. And the best way to go third ventricular surface is contralateral paramedian. Because with this way, just with the suprapineal recess, you can reach the tumor. Again, without touching any normal tissue. And this is after resection. Contralateral supracerebellar transtentorial approach for the third ventricular surface of the thalamus. And it was grade I tumor. And the tumor like this is strange. Thalamic tumors, even the malignant thalamic tumors, do not go to hypothalamus. Hypothalamic tumors do not go to thalamus. So in this case, this looks like hypothalamic and thalamic tumors. So something is wrong. Because this is lymphoma. So we should not operate them. And the adjuvant treatment is useful for lymphoma. Another problem is bilateral thalamic tumors. Unfortunately, I have nothing to do more than putting shunt or things. So this is still a main problem, the bilateral thalamic tumors. And the most important factor of outcome is the extent of resection and histopathology. And with low-grade tumors, you may cure the patient. And with high-grade tumors, there is no doubt you can extend the life of the patient. And good outcome is the smaller tumors and longer history with symptoms is a good outcome. If the patient has raised ICP symptoms and the short time is the worst outcome. And children has better outcome because more children tumors are benign. In adult cases, worse story. Most of the adult tumors are unfortunately malignant tumors. I operated 71 patients. Now I have more than 80. But this is the time. We published paper. 71 patients in 10 years. And I mostly used posterior intramuscular parasympathetic approach. But anterior transcallosal and paramedial supracerebellar is another one. Stereotoxic biopsy in four cases. And in most of the cases, I operated one. And the second operation, malignant tumors. And if there is a recurrence, I operate again. Third, fourth, fifth operations are mostly because of the CSF. All headache from the myotelomic surgery coming from CSF. CSF, I never know what CSF will do. Sometimes we may have a unilateral problem. Sometimes bilateral. Sometimes you put external drainage. So in one patient, I operated five times. Because I removed one time tumor, but I operated four times because of the CSF problem. So CSF problem is the main problem. For this reason, if possible, I prefer anterior transcallosal. Same time, I can do third ventriculostomy. This may save the life. Anyway, half of the patients are malignant. And the rest of them benign tumors. And no surgical mortality or major morbidity. And most GBM patients, slightly worse two months following surgery. But these are mostly the CSF problems patients also. And most of the patients, same or better than preoperative period. Meninges has to tailor to individual patient in thalamic lesions. For surgical planning, neuroimaging is essential in evaluating the growth pattern and extent of the lesion. And thalamic tumors or cavernomas can be rejected, except even the AVMs. I have also AVM. And I still believe that surgery is very helpful in most of the patients. And prognosis depends on the histopathology. Sometimes when I operate crazy glioblastoma, I feel that I operate most difficult surgery, but nobody appreciate it. Even God doesn't appreciate if the glioblastoma, still the patients are dying. But still, we have to help the patients. Adjuvant therapy should be utilized depending on the histopathology. I thank you for your attention. I think I am on time. Unbelievable, unbelievable. Thank you very much. Any questions from the audience? I think you. Dr. Turei, wonderful and exciting white matter surgeries. And I want to ask a question. For unilateral thalamus lesion on the MR scan, maybe we think it's glioma and no obvious enhancement after contrastment. I have many cases. So without, you mean glioma without enhancement? Yeah. And I saw you in your 75 cases, you have 5% of the biopsy. I mean, what kind of situation you decide to biopsy? Biopsy. Yeah. Biopsy cases are lymphoma cases. You know, in lymphoma now, with MRI and CT scan, you can tell it's lymphoma. But still, they want sample. And we have to do biopsy. So the biopsy cases are lymphoma. And also the bilateral thalamic lesions, we have to, I don't like biopsy. And the biopsy of thalamus, in my opinion, more dangerous than my surgery. And I don't think that it is helpful so much. But if it's lymphoma, they want sample, yeah. Okay, thank you. Thank you, Dr. Al-Kamaluchi. Thank you for this nice presentation. My question is about the prognosis of this, between brackets, benign glioma, which we have cases that are not operated but diagnosed by stereotactic biopsy. They say grade II glioma. And some of them have just irradiation. And we are following these patients, as you have said, many, many years. Did you make any molecular studies to understand if there is a difference in this grade II glioma in this area, in the thalamus and in basal ganglia, compared to those of cortical and subcortical area? Or maybe it's seen in the literature? If it's an adult patient, I have also seen many cases that biopsy it somewhere else. And I have all the complicated thalamic lesions from Turkey. And I can see what's going on, more or less. If it's an adult patient, even if they call it low grade, it's immediately getting high grade. In the adult cases, I don't like to wait. You know, if it looks like a low grade tumor in thalamus in adults, I saw some cases, if you wait, they immediately get malignant. But in pediatric cases, they're mostly benign. They're mostly benign. But the adult patients, mostly malignant.

Dr. Ugur Turei

surgical approaches

thalamic tumors

thalamus

surgical treatment

neuroimaging