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Albert L. Rhoton - One of the best experts on this subject based on the ideXlab platform.
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meyer s loop and the optic radiations in the transSylvian approach to the mediobasal temporal lobe
Neurosurgery, 2006Co-Authors: Chan-young Choi, Pablo Rubino, Juan C Fernandezmiranda, Albert L. RhotonAbstract:OBJECTIVE: In the transSylvian approach to the mediobasal temporal structures, the temporal horn is approached through the floor of the Sylvian Fissure. The anterior bundle of the optic radiations (Meyer's loop) courses between the floor of the Sylvian Fissure and roof of the temporal horn and could be damaged in this approach. This study was designed to define the route through the floor of the Sylvian Fissure least likely to damage the optic pathways. METHODS: Meyer's loop was dissected by applying Klingler's fiber dissection technique in 10 formalin-fixed human hemispheres. Several measurements quantified the relationship of the Meyer's loop to surgically important structures. RESULTS: This study identified a triangular safe area below the floor of the Sylvian Fissure through which the temporal horn could be accessed in the transSylvian approach with a low risk of damaging the optic radiations. An incision in the floor of the Sylvian Fissure directed downward at the level of limen insula and the adjacent 5 mm of the inferior insular sulcus would avoid the optic radiations. An incision directed straight downward 10, 15, and 20 mm behind the limen in the inferior insular sulcus would cross Meyer's loop and would need to be directed downward and medially as much as 80 degrees from the sagittal plane to avoid Meyer's loop. CONCLUSION: In the transSylvian approach to the temporal horn, incisions at the level of the limen, or adjacent 5 mm of the inferior insular sulcus, are less likely to damage Meyer's loop and the optic radiations than more posterior incisions along the inferior insular sulcus. Incision at this safe level commonly opens into the amygdala, a portion of which is removed to provide entry into the temporal horn for removal of the mediobasal structures.
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meyer s loop and the optic radiations in the transSylvian approach to the mediobasal temporal lobe commentary
Neurosurgery, 2006Co-Authors: Chan-young Choi, Albert L. Rhoton, Pablo Rubino, Juan C Fernandezmiranda, Nobuhiro Mikuni, Nobuo Hashimoto, Evandro De Oliveira, Gazi M Yasargil, Saleem I Abdulrauf, Wolf LudemannAbstract:OBJECTIVE: In the transSylvian approach to the mediobasal temporal structures, the temporal horn is approached through the floor of the Sylvian Fissure. The anterior bundle of the optic radiations (Meyer's loop) courses between the floor of the Sylvian Fissure and roof of the temporal horn and could be damaged in this approach. This study was designed to define the route through the floor of the Sylvian Fissure least likely to damage the optic pathways. METHODS: Meyer's loop was dissected by applying Klingler's fiber dissection technique in 10 formalin-fixed human hemispheres. Several measurements quantified the relationship of the Meyer's loop to surgically important structures. RESULTS: This study identified a triangular safe area below the floor of the Sylvian Fissure through which the temporal horn could be accessed in the transSylvian approach with a low risk of damaging the optic radiations. An incision in the floor of the Sylvian Fissure directed downward at the level of limen insula and the adjacent 5 mm of the inferior insular sulcus would avoid the optic radiations. An incision directed straight downward 10, 15, and 20 mm behind the limen in the inferior insular sulcus would cross Meyer's loop and would need to be directed downward and medially as much as 80 degrees from the sagittal plane to avoid Meyer's loop. CONCLUSION: In the transSylvian approach to the temporal horn, incisions at the level of the limen, or adjacent 5 mm of the inferior insular sulcus, are less likely to damage Meyer's loop and the optic radiations than more posterior incisions along the inferior insular sulcus. Incision at this safe level commonly opens into the amygdala, a portion of which is removed to provide entry into the temporal horn for removal of the mediobasal structures.
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Microsurgical anatomy of the insula and the Sylvian Fissure
Journal of neurosurgery, 2004Co-Authors: Necmettin Tanriover, Albert L. Rhoton, Masatou Kawashima, Arthur J. Ulm, Alexandre YasudaAbstract:Object. The purpose of this study was to define the topographic anatomy, arterial supply, and venous drainage of the insula and Sylvian Fissure. Methods. The neural, arterial, and venous anatomy of the insula and Sylvian Fissure were examined in 43 cerebral hemispheres. Conclusions. The majority of gyri and sulci of the frontoparietal and temporal opercula had a constant relationship to the insular gyri and sulci and provided landmarks for approaching different parts of the insula. The most lateral lenticulostriate artery, an important landmark in insular surgery, arose 14.6 mm from the apex of the insula and penetrated the anterior perforated substance 15.3 mm medial to the limen insulae. The superior trunk of the middle cerebral artery (MCA) and its branches supplied the anterior, middle, and posterior short gyri; the anterior limiting sulcus; the short sulci; and the insular apex. The inferior trunk supplied the posterior long gyrus, inferior limiting sulcus, and limen area in most hemispheres. Both of these trunks frequently contributed to the supply of the central insular sulcus and the anterior long gyrus. The areas of insular supply of the superior and inferior trunks did not overlap. The most constant insular area of supply by the cortical MCA branches was from the prefrontal and precentral arteries that supplied the anterior and middle short gyri, respectively. The largest insular perforating arteries usually arose from the central and angular arteries and most commonly entered the posterior half of the central insular sulcus and posterior long gyrus. Insular veins drained predominantly to the deep middle cerebral vein, although frequent connections to the superficial venous system were found. Of all the insular veins, the precentral insular vein was the one that most commonly connected to the superficial Sylvian vein.
Jankarl Burkhardt - One of the best experts on this subject based on the ideXlab platform.
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occipital artery to middle cerebral artery bypass using the descending branch of the lateral circumflex femoral artery as an interposition graft for blood flow augmentation in progressive moyamoya disease
World Neurosurgery, 2020Co-Authors: Visish M Srinivasan, Peter Kan, Andrew T Huang, Jankarl BurkhardtAbstract:Background The superficial temporal artery to middle cerebral artery (MCA) end-to-side anastomosis is the most commonly used direct extracranial-intracranial bypasses type for Moyamoya disease (MMD). In progressive MMD without suitable scalp arteries, other bypass constructs may need to be considered to augment blood flow. Case Description We present the exceptional case of a 48-year-old woman with progressive MMD and repeated transient ischemic attacks originating from the right hemisphere despite previous bilateral bypasses. We used the descending branch of the lateral circumflex femoral artery as an interposition graft for an occipital artery to M4 MCA bypass with 2 end-to-side anastomoses to augment blood flow. The ipsilateral occipital artery had already formed bilateral transdural collaterals; the goal was to preserve its supply while using the artery as a donor for an interposition graft. Access to the Sylvian Fissure was limited because of the previous superficial temporal artery to MCA bypass with an extensive superficial collateral network necessitating preservation. The posterior aspect of the Sylvian Fissure was targeted to revascularize the posterior frontal and parietal region using an interposition graft matching the vessel size of a distal MCA vessel segment. Surgery was technically successful, without complications, and the patient recovered without new neurologic deficits. The bypass graft was patent on postoperative computed tomographic angiography and transcranioplasty ultrasound. Conclusions This case illustrates the need for creative bypass constructs in progressive MMD patients with multiple prior surgeries. Two surgical goals are paramount: flow augmentation with preservation of the existing collateral network to avoid complications and new deficits.
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selection strategy for optimal keyhole approaches for middle cerebral artery aneurysms lateral supraorbital versus minipterional craniotomy
World Neurosurgery, 2019Co-Authors: Giuseppe Esposito, Sandra Fernandes Dias, Jankarl Burkhardt, Jorn Fierstra, Carlo Serra, Oliver Bozinov, Luca RegliAbstract:Background/Objective The lateral supraorbital (LS) and minipterional (MP) approaches have been reported for treating intracranial aneurysms as alternative to the pterional approach. We describe our decision making for selecting the minicraniotomy, LS versus MP, for managing noncomplex aneurysms of the middle cerebral artery (MCA), based on the depth of the aneurysm within the Sylvian Fissure. Methods We report on a consecutive case series of 50 patients who underwent clipping of 54 ruptured/unruptured MCA aneurysms by means of LS or MP craniotomies. The distance between the MCA (M1) origin and the aneurysmal neck is key to selection of the approach: LS was used for MCA aneurysms Results 11 of 50 patients presented with subarachnoid hemorrhage (10 ruptured MCA aneurysms). Overall, 59 aneurysms were successfully clipped (54 of the MCA). The mean distance between the M1 origin and the aneurysmal neck was 10.1 mm (range, 4–17 mm) for patients treated by LS and 20 mm (range, 15–30 mm) for those treated by MP. All but 1 MCA aneurysms were successfully treated. At last follow-up (mean, 14 months), no reperfusion of the clipped aneurysms was observed. Conclusion Our strategy for selecting the keyhole approach based on the depth of the aneurysm within the Sylvian Fissure is efficient and safe. We suggest the use of the LS approach when the aneurysm is
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combination superficial temporal artery middle cerebral artery bypass and m2 m2 reanastomosis with trapping of a stented distal middle cerebral artery aneurysm 3 dimensional operative video
Operative Neurosurgery, 2018Co-Authors: Jankarl Burkhardt, Sonia Yousef, Halima Tabani, Arnau Benet, Roberto Rodriguez Rubio, Michael T. LawtonAbstract:Distal middle cerebral artery (MCA) aneurysms often have non-saccular morphology and cannot be clipped, requiring revascularization and trapping instead. Combination bypasses are needed when 2 arteries exit the aneurysm, and extracranial-intracranial and intracranial-intracranial bypasses can be used. This video demonstrates a combination bypass used to treat a previously stented distal MCA aneurysm with both a superficial temporal artery (STA)-to-MCA bypass and an M2-to-M2 reanastomosis. This 56-yr-old man presented with distal left-sided MCA aneurysm 2 years earlier and attempted stent-assisted coiling was aborted after the aneurysm was perforated with stenting alone. Follow-up angiography demonstrated progressive aneurysm enlargement, and he was referred for surgery. The patient consented for the procedure and a pterional craniotomy extended posteriorly exposed the distal Sylvian Fissure and efferent M4-cortical arteries. After splitting the Sylvian Fissure, the "flash fluorescence" technique with indocyanine green (ICG) videoangiography identified an M4 recipient artery from the deeper of 2 exiting branches for STA-MCA bypass.1 The aneurysm was then trapped, and inflow and the more superficial outflow arteries were anastomosed end to end (M2-M2 in-situ bypass). A platelet plug that developed at the reanastomosis site was broken apart with mechanical manipulation, and ICG videoangiography demonstrated patency of both bypasses. The patient recovered without any neurological deficits, and postoperative computed tomography angiography confirmed bypass patency. Combination bypasses are needed when unclippable bifurcation aneurysms require revascularization. Careful intraoperative evaluation of patency of the bypass is imperative and helps identifying and addressing any potential early bypass occlusion.
Luca Regli - One of the best experts on this subject based on the ideXlab platform.
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Microsurgical dissection of Sylvian Fissure—short technical videos of third generation cerebrovascular neurosurgeons
Acta Neurochirurgica, 2019Co-Authors: Sajjad Muhammad, Michael Lawton, Luca Regli, Rokuya Tanikawa, Mika Niemelä, Miikka KorjaAbstract:BackgroundMultiple intracranial pathologies, including aneurysms of the middle cerebral artery, distal basilar artery, and suprasellar pathologies require the microsurgical opening of the Sylvian Fissure. Delicate splitting of the arachnoid and safe microdissection of the veins, arteries, and brain parenchyma is the key to successful surgery through the Sylvian Fissure corridor. We hypothesize that the geographical and historical environment in which neurosurgeons learn their operative skills is subject to a number of extrinsic influences, including cultural nuances of surgical techniques. Here we try to illustrate some cultural differences and technical aspects of the opening of the Sylvian Fissure by four “third generation” cerebrovascular neurosurgeons from three different continents.MethodsIn the video analysis, various microsurgical aspects, including the opening style of the Sylvian Fissure, handedness, use of sharp or blunt microinstruments, use of retractors, use of high magnification, and handling of bridging veins are presented.ResultsThe video illustrates the two distinct Sylvian Fissure opening styles, namely sharp and blunt microdissection, as well as the extent of the opening namely a wide and focal splitting.ConclusionThe edited video underlines nuances and differences of a few major technical aspects that are perhaps typical to certain surgical environments and cultures. These microsurgical nuances and styles are useful pearls that can be mastered with training by any novice neurosurgeon.
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selection strategy for optimal keyhole approaches for middle cerebral artery aneurysms lateral supraorbital versus minipterional craniotomy
World Neurosurgery, 2019Co-Authors: Giuseppe Esposito, Sandra Fernandes Dias, Jankarl Burkhardt, Jorn Fierstra, Carlo Serra, Oliver Bozinov, Luca RegliAbstract:Background/Objective The lateral supraorbital (LS) and minipterional (MP) approaches have been reported for treating intracranial aneurysms as alternative to the pterional approach. We describe our decision making for selecting the minicraniotomy, LS versus MP, for managing noncomplex aneurysms of the middle cerebral artery (MCA), based on the depth of the aneurysm within the Sylvian Fissure. Methods We report on a consecutive case series of 50 patients who underwent clipping of 54 ruptured/unruptured MCA aneurysms by means of LS or MP craniotomies. The distance between the MCA (M1) origin and the aneurysmal neck is key to selection of the approach: LS was used for MCA aneurysms Results 11 of 50 patients presented with subarachnoid hemorrhage (10 ruptured MCA aneurysms). Overall, 59 aneurysms were successfully clipped (54 of the MCA). The mean distance between the M1 origin and the aneurysmal neck was 10.1 mm (range, 4–17 mm) for patients treated by LS and 20 mm (range, 15–30 mm) for those treated by MP. All but 1 MCA aneurysms were successfully treated. At last follow-up (mean, 14 months), no reperfusion of the clipped aneurysms was observed. Conclusion Our strategy for selecting the keyhole approach based on the depth of the aneurysm within the Sylvian Fissure is efficient and safe. We suggest the use of the LS approach when the aneurysm is
Robert F. Spetzler - One of the best experts on this subject based on the ideXlab platform.
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Ipsilateral Internal Carotid Artery Bifurcation Aneurysm and Contralateral Middle Cerebral Artery Aneurysm Clipping: 2-Dimensional Operative Video.
Operative Neurosurgery, 2019Co-Authors: Benjamin K Hendricks, Robert F. SpetzlerAbstract:Contralateral clipping of a middle cerebral artery (MCA) aneurysm is challenging but possible with favorable anatomy. This patient had bilateral aneurysms, an ipsilateral internal carotid artery bifurcation aneurysm and a contralateral MCA aneurysm. The surgical goal was to clip both aneurysms if possible. After opening the ipsilateral Sylvian Fissure, the arachnoid planes were opened along the anterior cerebral arteries to the contralateral Sylvian Fissure. The arachnoid planes within the Sylvian Fissure were dissected to permit visualization of the contralateral proximal MCA and anatomy, which permitted the MCA to be followed to the aneurysm. If adequate proximal and distal control is present, the aneurysm is clipped. The surgeon needs to be comfortable in backing out if the exposure is too limited. The sequence of clipping should be to clip the contralateral aneurysm first to avoid inadvertent manipulation of the ipsilateral clip during the contralateral procedure. Postoperative angiography demonstrated that the bilateral aneurysms were clipped and that all vessels were patent. The patient gave informed consent for surgery and video recording. Institutional review board approval was deemed unnecessary. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.
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incidence of superficial Sylvian vein compromise and postoperative effects on ct imaging after surgical clipping of middle cerebral artery aneurysms
American Journal of Neuroradiology, 2005Co-Authors: Bruce L Dean, Robert C Wallace, Joseph M Zabramski, Alan M Pitt, Roger C Bird, Robert F. SpetzlerAbstract:BACKGROUND AND PURPOSE: Dissection and retraction of the Sylvian Fissure can cause venous insufficiency and may be an important contributor to postoperative edema or hemorrhage after clipping of a middle cerebral artery (MCA) aneurysm. The incidence of changes in the superficial middle cerebral vein (SMCV) and adjacent veins and whether such changes increase the amount of edema or hemorrhage on postoperative CT is the focus of this study. METHODS: Pre- and postoperative angiograms of 100 consecutive patients with MCA aneurysms treated by craniotomy and clipping were compared to determine the postoperative incidence of changes involving the SMCV. CTs from the normal and abnormal postoperative venous groups were compared to determine the amount of edema or presence of parenchymal hemorrhage. RESULTS: Postoperatively, 31 (31%) SMCVs were altered, 20 to a minor or moderate degree. Eleven cases were pronounced. In 9 (9%) cases, the SMCV was completely obscured or failed to fill on postoperative angiography. More edema (observer 1, P < .0002; observer 2, P < .0006) and small brain parenchymal hemorrhages (observer 1, P < .00003; observer 2, P < .00001) were found on the postoperative CT images of the group whose SMCVs were altered than those that were unchanged. CONCLUSIONS: Neurosurgeons and neuroradiologists should be attentive to changes in the SMCV and adjacent venous structures to optimize outcomes of procedures involving the Sylvian Fissure.
Evandro De Oliveira - One of the best experts on this subject based on the ideXlab platform.
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MICROSURGICAL ANATOMY OF THE TEMPORAL LOBE: PART 2-Sylvian Fissure REGION AND ITS CLINICAL APPLICATION
LIPPINCOTT WILLIAMS & WILKINS, 2009Co-Authors: Wen, Hung Tzu, Evandro De Oliveira, Rhoton Jr., Albert L., Castro, Luiz Henrique M., Figueiredo, Eberval Gadelha, Teixeira, Manoel JacobsenAbstract:OBJECTIVE: We present observations of the anatomy of the Sylvian Fissure region and their clinical application in neuroimaging, microsurgery for middle cerebral artery aneurysms and insular lesions, frontobasal resections, and epilepsy Surgery. METHODS: Sixty adult cadaveric hemispheres and 12 adult cadaveric heads were studied after perfusion of the arteries and veins with colored latex. The anatomic information was applied in more than 200 microsurgeries in and around the Sylvian Fissure region in the past 15 years. RESULTS: The Sylvian Fissure extends from the basal to the lateral surface of the brain and presents 2 compartments on each surface, I superficial (temporal stem and its ramii) and 1 deep (anterior and lateral operculoinsular compartments). The temporal operculum is in opposition to the frontal and parietal opercula (planum polare versus inferior frontal and precentral gyri, Heschl`s versus postcentral gyri, planum temporale versus supramarginal gyrus). The inferior frontal, precentral, and postcentral gyri cover the anterior, middle, and posterior thirds of the lateral surface of the insula, respectively. The pars triangularis covers the apex of the insula, located immediately distal to the genu of the middle cerebral artery. The clinical application of the anatomic information presented in this article is in angiography, middle cerebral artery aneurysm surgery, insular resection, frontobasal resection, and amygdalohippocampectomy, and hemispherotomy. CONCLUSION: The anatomic relationships of the Sylvian Fissure region can be helpful in preoperative planning and can serve as reliable intraoperative navigation landmarks in microsurgery involving that region
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MICROSURGICAL ANATOMY OF THE TEMPORAL LOBE: PART 2-Sylvian Fissure REGION AND ITS CLINICAL APPLICATION
LIPPINCOTT WILLIAMS & WILKINS, 2009Co-Authors: Wen, Hung Tzu, Evandro De Oliveira, Rhoton Jr., Albert L., Castro, Luiz Henrique M., Figueiredo, Eberval Gadelha, Teixeira, Manoel JacobsenAbstract:OBJECTIVE: We present observations of the anatomy of the Sylvian Fissure region and their clinical application in neuroimaging, microsurgery for middle cerebral artery aneurysms and insular lesions, frontobasal resections, and epilepsy Surgery. METHODS: Sixty adult cadaveric hemispheres and 12 adult cadaveric heads were studied after perfusion of the arteries and veins with colored latex. The anatomic information was applied in more than 200 microsurgeries in and around the Sylvian Fissure region in the past 15 years. RESULTS: The Sylvian Fissure extends from the basal to the lateral surface of the brain and presents 2 compartments on each surface, I superficial (temporal stem and its ramii) and 1 deep (anterior and lateral operculoinsular compartments). The temporal operculum is in opposition to the frontal and parietal opercula (planum polare versus inferior frontal and precentral gyri, Heschl`s versus postcentral gyri, planum temporale versus supramarginal gyrus). The inferior frontal, precentral, and postcentral gyri cover the anterior, middle, and posterior thirds of the lateral surface of the insula, respectively. The pars triangularis covers the apex of the insula, located immediately distal to the genu of the middle cerebral artery. The clinical application of the anatomic information presented in this article is in angiography, middle cerebral artery aneurysm surgery, insular resection, frontobasal resection, and amygdalohippocampectomy, and hemispherotomy. CONCLUSION: The anatomic relationships of the Sylvian Fissure region can be helpful in preoperative planning and can serve as reliable intraoperative navigation landmarks in microsurgery involving that region.University of Florid
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meyer s loop and the optic radiations in the transSylvian approach to the mediobasal temporal lobe commentary
Neurosurgery, 2006Co-Authors: Chan-young Choi, Albert L. Rhoton, Pablo Rubino, Juan C Fernandezmiranda, Nobuhiro Mikuni, Nobuo Hashimoto, Evandro De Oliveira, Gazi M Yasargil, Saleem I Abdulrauf, Wolf LudemannAbstract:OBJECTIVE: In the transSylvian approach to the mediobasal temporal structures, the temporal horn is approached through the floor of the Sylvian Fissure. The anterior bundle of the optic radiations (Meyer's loop) courses between the floor of the Sylvian Fissure and roof of the temporal horn and could be damaged in this approach. This study was designed to define the route through the floor of the Sylvian Fissure least likely to damage the optic pathways. METHODS: Meyer's loop was dissected by applying Klingler's fiber dissection technique in 10 formalin-fixed human hemispheres. Several measurements quantified the relationship of the Meyer's loop to surgically important structures. RESULTS: This study identified a triangular safe area below the floor of the Sylvian Fissure through which the temporal horn could be accessed in the transSylvian approach with a low risk of damaging the optic radiations. An incision in the floor of the Sylvian Fissure directed downward at the level of limen insula and the adjacent 5 mm of the inferior insular sulcus would avoid the optic radiations. An incision directed straight downward 10, 15, and 20 mm behind the limen in the inferior insular sulcus would cross Meyer's loop and would need to be directed downward and medially as much as 80 degrees from the sagittal plane to avoid Meyer's loop. CONCLUSION: In the transSylvian approach to the temporal horn, incisions at the level of the limen, or adjacent 5 mm of the inferior insular sulcus, are less likely to damage Meyer's loop and the optic radiations than more posterior incisions along the inferior insular sulcus. Incision at this safe level commonly opens into the amygdala, a portion of which is removed to provide entry into the temporal horn for removal of the mediobasal structures.
