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Xiangen Shi - One of the best experts on this subject based on the ideXlab platform.
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serpentine aneurysm of the posterior cerebral Artery treated by internal Maxillary Artery bypass followed by parent Artery occlusion a case report and literature review
Acta Neurochirurgica, 2019Co-Authors: Jie Zhang, Hai Qian, Xiangen Shi, Fangjun Liu, Yuming Sun, Zhongqing ZhouAbstract:Serpentine aneurysms of the posterior cerebral Artery (PCA) treated by the internal Maxillary Artery (IMA) bypass are rare. Here, the authors report the case of a 34-year-old male patient who presented with a half-year history of gradual severe headache and right-sided limb monoparesis and paresthesia lasting for 1 week. Preoperative angiograms showed a serpentine aneurysm in the left distal PCA, which was treated with internal Maxillary Artery-radial Artery-posterior cerebral Artery (IMA-RA-PCA) bypass followed by parent Artery occlusion (PAO). The postoperative course was uneventful; radiological images revealed that the aneurysm disappeared, and there was good graft patency and excellent perfusion of the distal PCA territories. To the authors' knowledge, this is the first and only case of distal PCA serpentine aneurysm to be treated by IMA-RA-PCA bypass followed by proximal PAO. These findings suggest that IMA bypass surgery is a good and feasible treatment option for serpentine aneurysms of the PCA that can preserve the parent Artery. Moreover, the anatomic segments of the PCA and different treatment options available for PCA serpentine aneurysms are also discussed in this study.
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internal Maxillary Artery bypass for the treatment of complex middle cerebral Artery aneurysms
Neurosurgical Focus, 2019Co-Authors: Long Wang, Hai Qian, Li Cai, Rokuya Tanikawa, Xiangen ShiAbstract:OBJECTIVEThe rapid innovation of the endovascular armamentarium results in a decreased number of indications for a classic surgical approach. However, a middle cerebral Artery (MCA) aneurysm remains the best example of one for which results have favored microsurgery over endovascular intervention. In this study, the authors aimed to evaluate the experience and efficacy regarding surgical outcomes after applying internal Maxillary Artery (IMA) bypass for complex MCA aneurysms (CMCAAs).METHODSAll IMA bypasses performed between January 2010 and July 2018 in a single-center, single-surgeon practice were screened.RESULTSIn total, 12 patients (9 males, 3 females) with CMCAAs managed by high-flow IMA bypass were identified. The mean size of CMCAAs was 23.7 mm (range 10-37 mm), and the patients had a mean age of 31.7 years (range 14-56 years). The aneurysms were proximally occluded in 8 cases, completely trapped in 3 cases, and completely resected in 1 case. The radial Artery was used as the graft vessel in all cases. At discharge, the graft patency rate was 83.3% (n = 10), and all aneurysms were completely eliminated (83.3%, n = 10) or greatly diminished (16.7%, n = 2) from the circulation. Postoperative ischemia was detected in 2 patients as a result of graft occlusion, and 1 patient presenting with subarachnoid hemorrhage achieved improved modified Rankin Scale scores compared to the preoperative status but retained some neurological deficits. Therefore, neurological assessment at discharge showed that 9 of the 12 patients experienced unremarkable outcomes. The mean interval time from bypass to angiographic and clinical follow-up was 28.7 months (range 2-74 months) and 53.1 months (range 19-82 months), respectively. Although 2 grafts remained occluded, all aneurysms were isolated from the circulation, and no patient had an unfavorable outcome.CONCLUSIONSThe satisfactory result in the present study demonstrated that IMA bypass is a promising method for the treatment of CMCAAs and should be maintained in the neurosurgical armamentarium. However, cases with intraoperative radical resection or inappropriate bypass recipient selection such as aneurysmal wall should be meticulously chosen with respect to the subtype of MCA aneurysm.
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the history and evolution of internal Maxillary Artery bypass
World Neurosurgery, 2018Co-Authors: Long Wang, Michael T Lawton, Hai Qian, Li Cai, Xiangen ShiAbstract:Internal Maxillary Artery (IMA) bypass has gained momentum in the last 5 years for the treatment of complex cerebrovascular disorders and skull base tumors. However, some issues regarding this treatment modality have been proposed. As one of the most experienced neurosurgical teams to perform internal Maxillary Artery bypass in the world (>100 clinical cases), we reviewed the literature in aspects of basic anatomy of Maxillary Artery with its variations to the lateral pterygoid muscle, initial anastomosis modalities, and subsequent exposure techniques in cadaver studies, preoperative arterial evaluation methods, optimal interposed graft selections, and surgical outcome in the management of complex aneurysms, skull base tumors, and steno-occlusive disorders.
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internal Maxillary Artery bypass with radial Artery graft treatment of giant intracranial aneurysms
World Neurosurgery, 2017Co-Authors: Long Wang, Hai Qian, Xiangen ShiAbstract:Background Giant intracranial aneurysms (GIAs) can be approached via microsurgical and endovascular techniques. Use of flow diversion devices has yielded favorable outcomes, and indications for cerebral revascularization have dramatically decreased. Objective To evaluate the safety and validity of using internal Maxillary Artery (IMA) bypass with an interposed graft to treat GIAs. Methods During a 6-year period, high-flow IMA bypass procedures were performed in 32 patients with GIAs at our institute. Intraoperative Doppler sonography, indocyanine green, and postoperative angiography were used to assess the patency of the graft conduit and the stability of the aneurysm. Neurologic function was assessed with the modified Rankin Scale. Results The mean GIA size was 33.7 mm (range, 25.3–64 mm), and all showed a nonsaccular morphology, except for 1 patient who underwent a first attempt at surgical clipping of a saccular aneurysm. Complete occlusion (65.6%, n = 21) or great diminishment (28.1%, n = 9) of the GIA was shown in 30 patients and the graft patency rate was 90.6% ( n = 29). No deaths resulting from bypass surgery occurred. Functionally favorable outcomes (modified Rankin Scale score of 0–2) were recorded in 65.6% of patients at discharge, and the rate increased to 71.9% at the most recent follow-up (mean, 40.6 months). Surgical-related complications involving hydrocephalus and ischemic and hemorrhagic episodes were encountered in 5 patients, but 4 had complete regression of their neurologic symptoms. Conclusions Considering the grave natural history and treatment complexity of these lesions, this study showed satisfactory results in the treatment of GIAs with IMA bypass.
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measurement of blood flow in an intracranial Artery bypass from the internal Maxillary Artery by intraoperative duplex sonography
Journal of Ultrasound in Medicine, 2017Co-Authors: Xiangen Shi, Hai Qian, Shams Raza Brohi, Fangjun Liu, Yang YangAbstract:This study explored the hemodynamic characteristics of a subcranial-intracranial bypass from the internal Maxillary Artery by measuring blood flow on intraoperative duplex sonography. The hemodynamic parameters of the internal Maxillary Artery (n = 20), radial Artery (n = 20), internal Maxillary Artery-middle cerebral Artery bypass (n = 42), and internal Maxillary Artery-posterior cerebral Artery bypass (n = 9) were measured by intraoperative duplex sonography. There was no significant difference in the internal diameters of the internal Maxillary and radial arteries (mean ± SD, 2.51 ± 0.34 versus 2.56 ± 0.22 mm; P = .648). The mean radial Artery graft length for subcranial-intracranial bypasses was 88.5 ± 12.78 mm (95% confidence interval [CI], 80.8-90.2 mm). Internal Maxillary Artery-middle cerebral Artery bypasses required a shorter radial Artery graft than internal Maxillary Artery-posterior cerebral Artery bypasses (77.8 ± 2.47 versus 104.8 ± 4.77 mm; P = .001). The mean flow volumes were 85.3 ± 18.5 mL/min (95% CI, 76.6-93.9 mL/min) for the internal Maxillary Artery, 72.6 ± 26.4 mL/min (95% CI, 64.3-80.9 mL/min) for internal Maxillary Artery-middle cerebral Artery bypasses, and 45.4 ± 6.7 mL/min (95% CI, 40.7-50.0 mL/min) for internal Maxillary Artery-posterior cerebral Artery bypasses. All grafts were opened after the success of the salvage procedures had been established, and the early patency rates (1 month after the operation) were 95% for internal Maxillary Artery-middle cerebral Artery bypasses and 100% the internal Maxillary Artery-posterior cerebral Artery bypasses. Measurement of blood flow by intraoperative sonography can be helpful in decision making and predicting graft patency and success after neurosurgical bypass procedures.
Hai Qian - One of the best experts on this subject based on the ideXlab platform.
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serpentine aneurysm of the posterior cerebral Artery treated by internal Maxillary Artery bypass followed by parent Artery occlusion a case report and literature review
Acta Neurochirurgica, 2019Co-Authors: Jie Zhang, Hai Qian, Xiangen Shi, Fangjun Liu, Yuming Sun, Zhongqing ZhouAbstract:Serpentine aneurysms of the posterior cerebral Artery (PCA) treated by the internal Maxillary Artery (IMA) bypass are rare. Here, the authors report the case of a 34-year-old male patient who presented with a half-year history of gradual severe headache and right-sided limb monoparesis and paresthesia lasting for 1 week. Preoperative angiograms showed a serpentine aneurysm in the left distal PCA, which was treated with internal Maxillary Artery-radial Artery-posterior cerebral Artery (IMA-RA-PCA) bypass followed by parent Artery occlusion (PAO). The postoperative course was uneventful; radiological images revealed that the aneurysm disappeared, and there was good graft patency and excellent perfusion of the distal PCA territories. To the authors' knowledge, this is the first and only case of distal PCA serpentine aneurysm to be treated by IMA-RA-PCA bypass followed by proximal PAO. These findings suggest that IMA bypass surgery is a good and feasible treatment option for serpentine aneurysms of the PCA that can preserve the parent Artery. Moreover, the anatomic segments of the PCA and different treatment options available for PCA serpentine aneurysms are also discussed in this study.
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internal Maxillary Artery bypass for the treatment of complex middle cerebral Artery aneurysms
Neurosurgical Focus, 2019Co-Authors: Long Wang, Hai Qian, Li Cai, Rokuya Tanikawa, Xiangen ShiAbstract:OBJECTIVEThe rapid innovation of the endovascular armamentarium results in a decreased number of indications for a classic surgical approach. However, a middle cerebral Artery (MCA) aneurysm remains the best example of one for which results have favored microsurgery over endovascular intervention. In this study, the authors aimed to evaluate the experience and efficacy regarding surgical outcomes after applying internal Maxillary Artery (IMA) bypass for complex MCA aneurysms (CMCAAs).METHODSAll IMA bypasses performed between January 2010 and July 2018 in a single-center, single-surgeon practice were screened.RESULTSIn total, 12 patients (9 males, 3 females) with CMCAAs managed by high-flow IMA bypass were identified. The mean size of CMCAAs was 23.7 mm (range 10-37 mm), and the patients had a mean age of 31.7 years (range 14-56 years). The aneurysms were proximally occluded in 8 cases, completely trapped in 3 cases, and completely resected in 1 case. The radial Artery was used as the graft vessel in all cases. At discharge, the graft patency rate was 83.3% (n = 10), and all aneurysms were completely eliminated (83.3%, n = 10) or greatly diminished (16.7%, n = 2) from the circulation. Postoperative ischemia was detected in 2 patients as a result of graft occlusion, and 1 patient presenting with subarachnoid hemorrhage achieved improved modified Rankin Scale scores compared to the preoperative status but retained some neurological deficits. Therefore, neurological assessment at discharge showed that 9 of the 12 patients experienced unremarkable outcomes. The mean interval time from bypass to angiographic and clinical follow-up was 28.7 months (range 2-74 months) and 53.1 months (range 19-82 months), respectively. Although 2 grafts remained occluded, all aneurysms were isolated from the circulation, and no patient had an unfavorable outcome.CONCLUSIONSThe satisfactory result in the present study demonstrated that IMA bypass is a promising method for the treatment of CMCAAs and should be maintained in the neurosurgical armamentarium. However, cases with intraoperative radical resection or inappropriate bypass recipient selection such as aneurysmal wall should be meticulously chosen with respect to the subtype of MCA aneurysm.
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the history and evolution of internal Maxillary Artery bypass
World Neurosurgery, 2018Co-Authors: Long Wang, Michael T Lawton, Hai Qian, Li Cai, Xiangen ShiAbstract:Internal Maxillary Artery (IMA) bypass has gained momentum in the last 5 years for the treatment of complex cerebrovascular disorders and skull base tumors. However, some issues regarding this treatment modality have been proposed. As one of the most experienced neurosurgical teams to perform internal Maxillary Artery bypass in the world (>100 clinical cases), we reviewed the literature in aspects of basic anatomy of Maxillary Artery with its variations to the lateral pterygoid muscle, initial anastomosis modalities, and subsequent exposure techniques in cadaver studies, preoperative arterial evaluation methods, optimal interposed graft selections, and surgical outcome in the management of complex aneurysms, skull base tumors, and steno-occlusive disorders.
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internal Maxillary Artery bypass with radial Artery graft treatment of giant intracranial aneurysms
World Neurosurgery, 2017Co-Authors: Long Wang, Hai Qian, Xiangen ShiAbstract:Background Giant intracranial aneurysms (GIAs) can be approached via microsurgical and endovascular techniques. Use of flow diversion devices has yielded favorable outcomes, and indications for cerebral revascularization have dramatically decreased. Objective To evaluate the safety and validity of using internal Maxillary Artery (IMA) bypass with an interposed graft to treat GIAs. Methods During a 6-year period, high-flow IMA bypass procedures were performed in 32 patients with GIAs at our institute. Intraoperative Doppler sonography, indocyanine green, and postoperative angiography were used to assess the patency of the graft conduit and the stability of the aneurysm. Neurologic function was assessed with the modified Rankin Scale. Results The mean GIA size was 33.7 mm (range, 25.3–64 mm), and all showed a nonsaccular morphology, except for 1 patient who underwent a first attempt at surgical clipping of a saccular aneurysm. Complete occlusion (65.6%, n = 21) or great diminishment (28.1%, n = 9) of the GIA was shown in 30 patients and the graft patency rate was 90.6% ( n = 29). No deaths resulting from bypass surgery occurred. Functionally favorable outcomes (modified Rankin Scale score of 0–2) were recorded in 65.6% of patients at discharge, and the rate increased to 71.9% at the most recent follow-up (mean, 40.6 months). Surgical-related complications involving hydrocephalus and ischemic and hemorrhagic episodes were encountered in 5 patients, but 4 had complete regression of their neurologic symptoms. Conclusions Considering the grave natural history and treatment complexity of these lesions, this study showed satisfactory results in the treatment of GIAs with IMA bypass.
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flow reversal bypass surgery a treatment option for giant serpentine and dolichoectatic aneurysms internal Maxillary Artery bypass with an interposed radial Artery graft followed by parent Artery occlusion
Neurosurgical Review, 2017Co-Authors: Long Wang, Hai QianAbstract:Giant serpentine and dolichoectatic aneurysms (GSDAs) are a small subgroup of intracranial aneurysms that often have poor clinical outcomes and are hardly to be treated by either conservative or endovascular management. We assessed seven patients who underwent internal Maxillary Artery bypass using radial Artery graft interposition followed by parent Artery occlusion to treat GSDAs. Intraoperative Doppler ultrasonography was used to assess the patency of the graft. CT angiogram or DSA were used postoperatively. The patients received follow-up after discharge and their neurological outcomes were measured using the Glasgow Outcome Score. Postoperative angiogram demonstrated that all the grafted conduits were patent, and the aneurysms were absent in two and collapsed or shrank in five of the patients. The rate of normal life or independent daily activities after internal Maxillary Artery bypass in the anterior and posterior GSDA patients was 66.7 and 75 %, respectively. One patient experienced postoperative frontal ischemia and was managed conservatively. His symptoms had completely resolved at discharge. No patient encountered perforator’s occlusion in the series. During 2.6 years follow-up, six patients experienced favorable outcomes. One patient died in the third year after discharge attribute to unrelated disease. Based on the mechanism of flow reversal, internal Maxillary Artery bypass with radial Artery graft followed by patent Artery occlusion is an effective, minimally invasive treatment modality for select patients with GSDAs.
Arnau Benet - One of the best experts on this subject based on the ideXlab platform.
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internal Maxillary Artery to anterior circulation bypass with local interposition grafts using a minimally invasive approach surgical anatomy and technical feasibility
World Neurosurgery, 2018Co-Authors: Roberto Rodriguez Rubio, Olivia Kola, Arnau Benet, Adib A Abla, Sonia Yousef, Sirin Gandhi, Halima Tabani, Jankarl Burkhardt, Michael T LawtonAbstract:Background The internal Maxillary Artery (IMA) is a reliable donor for extracranial–intracranial high-flow bypasses. However, previously described landmarks and techniques to harvest the IMA are complex and confusing and require extensive bone drilling, carrying significant neurovascular risk. The objective of our study was to describe a minimally invasive technique for exposing the IMA and to assess the feasibility of using the IMA as a donor for anterior-circulation recipient vessels using 2 different local interposition vessels. Methods Via a minimally invasive technique, the IMA was harvested in 10 cadaveric specimens and a pterional craniotomy was performed. Two interposition grafts—the superficial temporal Artery (STA) and middle temporal Artery—were evaluated individually. Transsylvian exposure of the second segment of middle cerebral Artery (M2), the supraclinoid internal carotid Artery, and the proximal postcommunicating anterior cerebral Artery segment was completed. Relevant vessel calibers and graft lengths were measured for each bypass model. Results The mean caliber of the IMA was 2.7 ± 0.5 mm. Of all 3 recipients, the shortest graft length was seen in the IMA-STA-M2 bypass, measuring 42.0 ± 8.4 mm. There was a good caliber match between the M2 (2.4 ± 0.4 mm) and STA (2.3 ± 0.4 mm) at the anastomotic site. The harvested middle temporal Artery was sufficient in length in only 30% cases, with a mean distal caliber of 2.0 ± 0.7 mm. Conclusions This study confirmed the technical feasibility of IMA as a donor for an extracranial–intracranial bypass to the second segment of the anterior cerebral Artery, M2, and the supraclinoid internal carotid Artery. However, IMA-STA-M2 was observed to be the most suitable bypass model.
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In Reply: Minimally Invasive Exposure of the Maxillary Artery at the Anteromedial Infratemporal Fossa.
Operative Neurosurgery, 2018Co-Authors: Roberto Rodriguez Rubio, Olivia Kola, Michael T Lawton, Arnau BenetAbstract:BACKGROUND The Maxillary Artery (MA) has been described as a reliable donor for extracranial-intracranial high-flow bypass. Existing techniques to harvest MA require brain retraction and drilling of the middle fossa (with or without a zygomatic osteotomy), carrying the potential risks of venous bleeding, injury to the branches of the Maxillary or mandibular nerves, muscular transection, or temporomandibular junction disorders. OBJECTIVE To describe a novel technique to expose the MA without bony drilling and with minimal impact to surrounding structures. METHODS A conventional curvilinear incision was performed in 10 cadaveric specimens, prior to elevating the scalp to expose the zygomatic root and lateral orbital rim. The sphenozygomatic suture was followed to the anterolateral edge of the inferior orbital fissure (IOF) to locate and harvest the pterygoid segment of the MA. Topographic anatomy was assessed using surrounding landmarks and 3D Cartesian coordinates to define the surgical area. The number of visible MA branches and their lengths were recorded. RESULTS The MA was successfully exposed in all specimens. This approach allowed 6 branches of MA to be exposed. The average length of exposure was 23.3 ± 8.3 mm and the average surgical area was 2.8 ± 0.9 cm2. The IOF was 11.5 ± 4.2 mm from the MA. CONCLUSION Our technique provides landmarks to identify the distal pterygoid segment of MA as a donor for extracranial-intracranial bypasses without the need for additional craniectomies. Clear anatomical landmarks, including the sphenozygomatic suture, anterolateral edge of IOF, infraorbital Artery, and the pterygoMaxillary fissure defined a trajectory to efficiently localize the MA with minimal risk to surrounding structures.
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internal Maxillary Artery to upper posterior circulation bypass using a superficial temporal Artery graft surgical anatomy and feasibility assessment
World Neurosurgery, 2017Co-Authors: Ali Tayebi Meybodi, Michael T Lawton, Roberto Rodriguez Rubio, Sonia Yousef, Xiaoming Guo, Xuequan Feng, Arnau BenetAbstract:Background Revascularization of the upper posterior circulation (UPC), including the superior cerebellar Artery (SCA) and posterior cerebral Artery (PCA), may be necessary as part of the surgical treatment of complex UPC aneurysms or vertebrobasilar insufficiency. The existing bypass options have relative advantages and disadvantages. However, the use of a superficial temporal Artery graft (STAg) in a bypass from the internal Maxillary Artery (IMA) to the UPC has not been previously assessed. We studied the surgical anatomy and assessed the technical feasibility of the IMA-STAg-UPC bypass. Methods Fourteen cadaver heads were studied. The STAg was harvested proximally from about 15 mm below the zygomatic arch. The IMA was exposed through the lateral triangle of the middle fossa. The IMA-STAg-UPC bypass was completed using a subtemporal approach. Results The bypass was successfully performed in all specimens. The average length of the STAg from the donor to the recipient was 46.4 mm for the s2 SCA, and 49.5 mm for the P2 PCA. The average distal diameter of the STAg was 2.3 mm. More than 83% of STAgs had a diameter of ≥2 mm distally. At the point of anastomosis, the average diameter of the SCA was 1.9 mm, and the average diameter of the PCA was 3.0 mm. Conclusions The proposed bypass is anatomically feasible and provides a suitable caliber match between the bypass components. Our results provide the anatomic basis for clinical assessment of the bypass in tackling complex lesions of the vertebrobasilar system requiring revascularization.
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surgical technique for high flow internal Maxillary Artery to middle cerebral Artery bypass using a superficial temporal Artery interposition graft
Operative Neurosurgery, 2017Co-Authors: Xuequan Feng, Michael T Lawton, Ivan H Elsayed, Ali Tayebi Meybodi, Jordina Rincontorroella, Arnau BenetAbstract:BACKGROUND: Extracranial-to-intracranial high-flow bypass often requires cranial, cervical, and graft site incisions. The internal Maxillary Artery (IMA) has been proposed as a donor to decrease invasiveness, but its length is insufficient for direct intracranial bypass. We report interposition of a superficial temporal Artery (STA) graft for high-flow IMA to middle cerebral Artery (MCA) bypass using a middle fossa approach. OBJECTIVE: To assess the feasibility of an IMA-STA graft-MCA bypass using a new middle fossa approach. METHODS: Twelve specimens were studied. A 7.5-cm STA graft was obtained starting 1.5 cm below the zygomatic arch. The calibers of STA were measured. After a pterional craniotomy, the IMA was isolated inside the infratemporal fossa through a craniectomy within the lateral triangle (lateral to the posterolateral triangle) in the middle fossa and transposed for proximal end-to-end anastomosis to the STA. The Sylvian fissure was split exposing the insular segment of the MCA, and an STA-M2 end-to-side anastomosis was completed. Finally, the length of graft vessel was measured. RESULTS: Average diameters of the proximal and distal STA ends were 2.3 ± 0.2 and 2.0 ± 0.1 mm, respectively. At the anastomosis site, the diameter of the IMA was 2.4 ± 0.6 mm, and the MCA diameter was 2.3 ± 0.3 mm. The length of STA graft required was 56.0 ± 5.9 mm. CONCLUSION: The STA can be used as an interposition graft for high-flow IMA-MCA bypass if the STA is obtained 1.5 cm below the zygomatic arch and the IMA is harvested through the proposed approach. This procedure may provide an efficient and less invasive alternative for high-flow EC-IC bypass.
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the lateral triangle of the middle fossa surgical anatomy and a novel technique for transcranial exposure of the internal Maxillary Artery
Neurosurgery, 2015Co-Authors: Xuequan Feng, Michael T Lawton, Ivan H Elsayed, Ali Tayebi Meybodi, Jordina Rincontorroella, Arnau BenetAbstract:Abstract The challenge of locating and isolating the internal Maxillary Artery (IMA) hinders its potential use as an arterial donor for extracranial-to-intracranial bypass surgery. To introduce a new approach through the middle cranial fossa for easy access and safe exposure of the IMA. Ten specimens were prepared for surgical simulation. After the pterional craniotomy, a 2-step drilling technique was performed (lateral triangle). First, a triangular craniectomy was completed anterolateral to the foramen spinosum. By following the middle meningeal Artery and dividing the lateral pterygoid muscle, the proximal part of IMA was located. Second, a bone slot was drilled in a posterior-to-anterior direction from the anterior aspect of the first craniectomy. By tracing of the proximal part, the main trunk of the IMA was obtained. The size of the 2 craniectomies, the depth of IMA from the surface of the middle fossa, and the length of exposed IMA were measured. Drilling within the lateral triangle allowed safe exposure of both the trunk and the branches of the mandibular nerve of the IMA. The total craniectomy measured 27.8 ± 4.2 mm in the anterior-posterior direction, and the posterior portion measured 13.3 ± 1.5 mm in the lateral-medial direction. The depth from the middle fossa to the IMA (16.8 ± 3.2 mm, mean ± SD) was equal to the length of IMA exposed (17.6 ± 3.3 mm, mean ± SD; P > .05). This new approach provides an efficient and safe method to consistently find and isolate a segment of the IMA suitable for extracranial-to-intracranial bypass. IMA, internal Maxillary ArteryLP, lateral pterygoidMMA, middle meningeal Artery.
Long Wang - One of the best experts on this subject based on the ideXlab platform.
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internal Maxillary Artery bypass for the treatment of complex middle cerebral Artery aneurysms
Neurosurgical Focus, 2019Co-Authors: Long Wang, Hai Qian, Li Cai, Rokuya Tanikawa, Xiangen ShiAbstract:OBJECTIVEThe rapid innovation of the endovascular armamentarium results in a decreased number of indications for a classic surgical approach. However, a middle cerebral Artery (MCA) aneurysm remains the best example of one for which results have favored microsurgery over endovascular intervention. In this study, the authors aimed to evaluate the experience and efficacy regarding surgical outcomes after applying internal Maxillary Artery (IMA) bypass for complex MCA aneurysms (CMCAAs).METHODSAll IMA bypasses performed between January 2010 and July 2018 in a single-center, single-surgeon practice were screened.RESULTSIn total, 12 patients (9 males, 3 females) with CMCAAs managed by high-flow IMA bypass were identified. The mean size of CMCAAs was 23.7 mm (range 10-37 mm), and the patients had a mean age of 31.7 years (range 14-56 years). The aneurysms were proximally occluded in 8 cases, completely trapped in 3 cases, and completely resected in 1 case. The radial Artery was used as the graft vessel in all cases. At discharge, the graft patency rate was 83.3% (n = 10), and all aneurysms were completely eliminated (83.3%, n = 10) or greatly diminished (16.7%, n = 2) from the circulation. Postoperative ischemia was detected in 2 patients as a result of graft occlusion, and 1 patient presenting with subarachnoid hemorrhage achieved improved modified Rankin Scale scores compared to the preoperative status but retained some neurological deficits. Therefore, neurological assessment at discharge showed that 9 of the 12 patients experienced unremarkable outcomes. The mean interval time from bypass to angiographic and clinical follow-up was 28.7 months (range 2-74 months) and 53.1 months (range 19-82 months), respectively. Although 2 grafts remained occluded, all aneurysms were isolated from the circulation, and no patient had an unfavorable outcome.CONCLUSIONSThe satisfactory result in the present study demonstrated that IMA bypass is a promising method for the treatment of CMCAAs and should be maintained in the neurosurgical armamentarium. However, cases with intraoperative radical resection or inappropriate bypass recipient selection such as aneurysmal wall should be meticulously chosen with respect to the subtype of MCA aneurysm.
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the history and evolution of internal Maxillary Artery bypass
World Neurosurgery, 2018Co-Authors: Long Wang, Michael T Lawton, Hai Qian, Li Cai, Xiangen ShiAbstract:Internal Maxillary Artery (IMA) bypass has gained momentum in the last 5 years for the treatment of complex cerebrovascular disorders and skull base tumors. However, some issues regarding this treatment modality have been proposed. As one of the most experienced neurosurgical teams to perform internal Maxillary Artery bypass in the world (>100 clinical cases), we reviewed the literature in aspects of basic anatomy of Maxillary Artery with its variations to the lateral pterygoid muscle, initial anastomosis modalities, and subsequent exposure techniques in cadaver studies, preoperative arterial evaluation methods, optimal interposed graft selections, and surgical outcome in the management of complex aneurysms, skull base tumors, and steno-occlusive disorders.
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internal Maxillary Artery bypass with radial Artery graft treatment of giant intracranial aneurysms
World Neurosurgery, 2017Co-Authors: Long Wang, Hai Qian, Xiangen ShiAbstract:Background Giant intracranial aneurysms (GIAs) can be approached via microsurgical and endovascular techniques. Use of flow diversion devices has yielded favorable outcomes, and indications for cerebral revascularization have dramatically decreased. Objective To evaluate the safety and validity of using internal Maxillary Artery (IMA) bypass with an interposed graft to treat GIAs. Methods During a 6-year period, high-flow IMA bypass procedures were performed in 32 patients with GIAs at our institute. Intraoperative Doppler sonography, indocyanine green, and postoperative angiography were used to assess the patency of the graft conduit and the stability of the aneurysm. Neurologic function was assessed with the modified Rankin Scale. Results The mean GIA size was 33.7 mm (range, 25.3–64 mm), and all showed a nonsaccular morphology, except for 1 patient who underwent a first attempt at surgical clipping of a saccular aneurysm. Complete occlusion (65.6%, n = 21) or great diminishment (28.1%, n = 9) of the GIA was shown in 30 patients and the graft patency rate was 90.6% ( n = 29). No deaths resulting from bypass surgery occurred. Functionally favorable outcomes (modified Rankin Scale score of 0–2) were recorded in 65.6% of patients at discharge, and the rate increased to 71.9% at the most recent follow-up (mean, 40.6 months). Surgical-related complications involving hydrocephalus and ischemic and hemorrhagic episodes were encountered in 5 patients, but 4 had complete regression of their neurologic symptoms. Conclusions Considering the grave natural history and treatment complexity of these lesions, this study showed satisfactory results in the treatment of GIAs with IMA bypass.
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flow reversal bypass surgery a treatment option for giant serpentine and dolichoectatic aneurysms internal Maxillary Artery bypass with an interposed radial Artery graft followed by parent Artery occlusion
Neurosurgical Review, 2017Co-Authors: Long Wang, Hai QianAbstract:Giant serpentine and dolichoectatic aneurysms (GSDAs) are a small subgroup of intracranial aneurysms that often have poor clinical outcomes and are hardly to be treated by either conservative or endovascular management. We assessed seven patients who underwent internal Maxillary Artery bypass using radial Artery graft interposition followed by parent Artery occlusion to treat GSDAs. Intraoperative Doppler ultrasonography was used to assess the patency of the graft. CT angiogram or DSA were used postoperatively. The patients received follow-up after discharge and their neurological outcomes were measured using the Glasgow Outcome Score. Postoperative angiogram demonstrated that all the grafted conduits were patent, and the aneurysms were absent in two and collapsed or shrank in five of the patients. The rate of normal life or independent daily activities after internal Maxillary Artery bypass in the anterior and posterior GSDA patients was 66.7 and 75 %, respectively. One patient experienced postoperative frontal ischemia and was managed conservatively. His symptoms had completely resolved at discharge. No patient encountered perforator’s occlusion in the series. During 2.6 years follow-up, six patients experienced favorable outcomes. One patient died in the third year after discharge attribute to unrelated disease. Based on the mechanism of flow reversal, internal Maxillary Artery bypass with radial Artery graft followed by patent Artery occlusion is an effective, minimally invasive treatment modality for select patients with GSDAs.
Roberto Rodriguez Rubio - One of the best experts on this subject based on the ideXlab platform.
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microsurgical techniques for exposing the internal Maxillary Artery in cerebral revascularization surgery a comparative cadaver study
World Neurosurgery, 2020Co-Authors: Atakan Orscelik, Olivia Kola, Vera Vigo, Ivan H Elsayed, Adib A Abla, Roberto Rodriguez RubioAbstract:Background The internal Maxillary Artery (IMAX) is currently considered one of the main donor vessels in extracranial-to-intracranial bypass surgeries. Four main techniques for harvesting the IMAX have been described: via the anterior medial infratemporal fossa (AMITF), the middle infratemporal fossa (MITF), the anterior lateral middle fossa (ALMF), and the lateral middle fossa (LMF). The advantages and limitations of these techniques have not yet been systematically evaluated and compared. Methods Twenty-five cadaver specimens were used to evaluate the harvesting technique. The length and the caliber of the targeted IMAX segments, as well as the depth from the operating plane to the IMAX, surgical time, and surgical area of exposure, were analyzed. Results The MITF technique provided the greatest operating area of exposure (mean, 3.88 ± 0.97 cm2). The LMF and MITF techniques provided the largest IMAX caliber (mean, 3.1 ± 0.4 mm and 3.0 ± 0.3 mm, respectively). The ALMF technique provided the shallowest operative depth as well as the least time of exposure (21.8 minutes). The MITF technique exposed the longest IMAX segment (mean, 18.8 ± 3.5 mm). Conclusions Advantages of the AMITF and MITF techniques include anatomic simplicity, absence of skull base drilling, and greater discretion in muscle dissection. These properties can simplify the anastomosis procedure compared with the ALMF and LMF techniques. Identification of the IMAX pattern is important before selecting the approach for this bypass operation.
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microsurgical techniques for exposing the internal Maxillary Artery in cerebral revascularization surgery a comparative cadaver study
World Neurosurgery, 2020Co-Authors: Olivia Kola, Xiong Li, Atakan Orscelik, Vera Vigo, Ivan H Elsayed, Adib A Abla, Roberto Rodriguez RubioAbstract:Abstract. Background The internal Maxillary Artery (IMAX) is currently considered one of the main donor vessels in extracranial-to-intracranial bypass surgeries. Four main techniques have been described for harvesting the IMAX, i.e., via the anterior medial infratemporal fossa (AMITF), the middle infratemporal fossa (MITF), the anterior lateral middle fossa (ALMF), and the lateral middle fossa (LMF). However, the advantages and limitations of these techniques have not been systematically evaluated and compared. Technique Twenty-five cadaveric specimens were used to evaluate the harvesting technique. The length and the caliber of the targeted IMAX segments as well as the depth from the operating plane to the IMAX, surgical time, and the surgical area of exposure were analyzed. Result The MITF technique provided the greatest operating area of exposure (3.88 ± 0.97 cm2. The LMF and MITF techniques provided the largest IMAX caliber (3.1 ± 0.4 mm and 3.0 ± 0.3 mm). The ALMF technique provided the minimum operative depth as well as the least time of exposure (21.8 min). The MITF technique exposed the longest IMAX segment (18.8 ± 3.5 mm). Conclusion Advantages of the AMITF and MITF techniques include anatomic simplicity, no skull base drilling, and greater discretion in muscle dissection. they both can simplify the whole anastomosis procedure than the ALMF and LMF techniques. Identification of the IMAX pattern is important before selecting the approach technique for the bypass operation.
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internal Maxillary Artery to anterior circulation bypass with local interposition grafts using a minimally invasive approach surgical anatomy and technical feasibility
World Neurosurgery, 2018Co-Authors: Roberto Rodriguez Rubio, Olivia Kola, Arnau Benet, Adib A Abla, Sonia Yousef, Sirin Gandhi, Halima Tabani, Jankarl Burkhardt, Michael T LawtonAbstract:Background The internal Maxillary Artery (IMA) is a reliable donor for extracranial–intracranial high-flow bypasses. However, previously described landmarks and techniques to harvest the IMA are complex and confusing and require extensive bone drilling, carrying significant neurovascular risk. The objective of our study was to describe a minimally invasive technique for exposing the IMA and to assess the feasibility of using the IMA as a donor for anterior-circulation recipient vessels using 2 different local interposition vessels. Methods Via a minimally invasive technique, the IMA was harvested in 10 cadaveric specimens and a pterional craniotomy was performed. Two interposition grafts—the superficial temporal Artery (STA) and middle temporal Artery—were evaluated individually. Transsylvian exposure of the second segment of middle cerebral Artery (M2), the supraclinoid internal carotid Artery, and the proximal postcommunicating anterior cerebral Artery segment was completed. Relevant vessel calibers and graft lengths were measured for each bypass model. Results The mean caliber of the IMA was 2.7 ± 0.5 mm. Of all 3 recipients, the shortest graft length was seen in the IMA-STA-M2 bypass, measuring 42.0 ± 8.4 mm. There was a good caliber match between the M2 (2.4 ± 0.4 mm) and STA (2.3 ± 0.4 mm) at the anastomotic site. The harvested middle temporal Artery was sufficient in length in only 30% cases, with a mean distal caliber of 2.0 ± 0.7 mm. Conclusions This study confirmed the technical feasibility of IMA as a donor for an extracranial–intracranial bypass to the second segment of the anterior cerebral Artery, M2, and the supraclinoid internal carotid Artery. However, IMA-STA-M2 was observed to be the most suitable bypass model.
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In Reply: Minimally Invasive Exposure of the Maxillary Artery at the Anteromedial Infratemporal Fossa.
Operative Neurosurgery, 2018Co-Authors: Roberto Rodriguez Rubio, Olivia Kola, Michael T Lawton, Arnau BenetAbstract:BACKGROUND The Maxillary Artery (MA) has been described as a reliable donor for extracranial-intracranial high-flow bypass. Existing techniques to harvest MA require brain retraction and drilling of the middle fossa (with or without a zygomatic osteotomy), carrying the potential risks of venous bleeding, injury to the branches of the Maxillary or mandibular nerves, muscular transection, or temporomandibular junction disorders. OBJECTIVE To describe a novel technique to expose the MA without bony drilling and with minimal impact to surrounding structures. METHODS A conventional curvilinear incision was performed in 10 cadaveric specimens, prior to elevating the scalp to expose the zygomatic root and lateral orbital rim. The sphenozygomatic suture was followed to the anterolateral edge of the inferior orbital fissure (IOF) to locate and harvest the pterygoid segment of the MA. Topographic anatomy was assessed using surrounding landmarks and 3D Cartesian coordinates to define the surgical area. The number of visible MA branches and their lengths were recorded. RESULTS The MA was successfully exposed in all specimens. This approach allowed 6 branches of MA to be exposed. The average length of exposure was 23.3 ± 8.3 mm and the average surgical area was 2.8 ± 0.9 cm2. The IOF was 11.5 ± 4.2 mm from the MA. CONCLUSION Our technique provides landmarks to identify the distal pterygoid segment of MA as a donor for extracranial-intracranial bypasses without the need for additional craniectomies. Clear anatomical landmarks, including the sphenozygomatic suture, anterolateral edge of IOF, infraorbital Artery, and the pterygoMaxillary fissure defined a trajectory to efficiently localize the MA with minimal risk to surrounding structures.
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internal Maxillary Artery to upper posterior circulation bypass using a superficial temporal Artery graft surgical anatomy and feasibility assessment
World Neurosurgery, 2017Co-Authors: Ali Tayebi Meybodi, Michael T Lawton, Roberto Rodriguez Rubio, Sonia Yousef, Xiaoming Guo, Xuequan Feng, Arnau BenetAbstract:Background Revascularization of the upper posterior circulation (UPC), including the superior cerebellar Artery (SCA) and posterior cerebral Artery (PCA), may be necessary as part of the surgical treatment of complex UPC aneurysms or vertebrobasilar insufficiency. The existing bypass options have relative advantages and disadvantages. However, the use of a superficial temporal Artery graft (STAg) in a bypass from the internal Maxillary Artery (IMA) to the UPC has not been previously assessed. We studied the surgical anatomy and assessed the technical feasibility of the IMA-STAg-UPC bypass. Methods Fourteen cadaver heads were studied. The STAg was harvested proximally from about 15 mm below the zygomatic arch. The IMA was exposed through the lateral triangle of the middle fossa. The IMA-STAg-UPC bypass was completed using a subtemporal approach. Results The bypass was successfully performed in all specimens. The average length of the STAg from the donor to the recipient was 46.4 mm for the s2 SCA, and 49.5 mm for the P2 PCA. The average distal diameter of the STAg was 2.3 mm. More than 83% of STAgs had a diameter of ≥2 mm distally. At the point of anastomosis, the average diameter of the SCA was 1.9 mm, and the average diameter of the PCA was 3.0 mm. Conclusions The proposed bypass is anatomically feasible and provides a suitable caliber match between the bypass components. Our results provide the anatomic basis for clinical assessment of the bypass in tackling complex lesions of the vertebrobasilar system requiring revascularization.