Microsurgical thrombectomy: where the ancient art meets the new era.

Mechanical thrombectomy (MT) is the leading treatment for acute large vessel occlusion (LVO). However, surgical thrombectomy (ST) may have a role in well selected LVO patients where MT failed to re-establish flow, the endovascular route is inaccessible, or where MT is a financially prohibitive or absent option (developing and poor countries). We compared the efficacy and efficiency between ST and MT, and described our operative experience and its potential application in the developing world. Clinical outcomes, procedural times, and efficacy of treatment were compared between the MT and ST of acute LVO between 2012 and 2022. Propensity score-matched analysis was also conducted to compare MT and ST. One-hundred nine patients fulfilled the study criteria (77 MTs vs 32 STs). Factors driving outcome were age (aOR: 0.95, 95%CI, 0.91-0.98), hemisphere side (aOR: 0.38, 95%CI, 0.15-0.96), and DWI-ASPECT (aOR: 1.39, 95%CI, 1.09-1.77) at presentation by the multivariate analysis. Times from door-start of procedure (P = 0.45) and start of procedure-recanalization (P = 0.13) were similar between treatment options. Propensity score-matched analysis found no significant difference for 2 treatment methods about time of door to recanalization (P = 0.155) and outcome (P = 0.221). The prognosticators of thrombectomy for acute LVO in patients with successful recanalization were age, affected hemisphere side, and DWI-ASPECT score. Our evidence shows that the efficacy of ST is similar to that of MT. There should be a place of ST for cases of mechanical failure or tandem cervical ICA and MCA occlusion. ST may be a temporizing LVO treatment option in healthcare systems where MT is inexistent or financially prohibitive to patients.

Bypass Surgery for Vertebral Artery and Posterior Inferior Cerebellar Artery Fusiform Aneurysms: Surgical Technique and Key Lessons.

Fusiform vertebral artery (VA) aneurysms are challenging to treat due to their pathophysiology, morphology, and anatomic location.1,2 Endovascular treatments are considered to be a widely adopted safe option for this pathology.1 Open microsurgical treatment is considered for complex anatomy, important branch involvement, poor collateral flow, or failed endovascular therapy.3-7 This report aims to show the flow-replacement strategy and bypass technique for a VA aneurysm with complex anatomy and branch involvement. A 24-year-old man presented to our clinic with a bilateral fusiform VA aneurysm discovered during workup of progressive headaches. Further investigation revealed that the left-side aneurysm was mostly thrombosed and the posterior inferior cerebellar artery arose from the aneurysm dome with a fusiform enlargement within a few millimeters from the branching point. After evaluating all management options, the patient decided on surgical treatment of the left VA aneurysm. We performed an occipital artery to posterior inferior cerebellar artery end-to-side anastomosis distal to the fusiform enlargement, followed by trapping of the aneurysm and dome resection (Video 1). Antegrade flow to the distal VA was reestablished using a radial artery interposition graft, thus preventing any flow alterations that may cause growth or rupture of the contralateral aneurysm caused by increased hemodynamic stress if the ipsilateral VA flow is not preserved.8 After in-hospital physical rehabilitation, the patient was discharged with a modified Rankin Scale score of 1. The contralateral aneurysm is managed with serial imaging and treatment will ensue if there is clinical-radiologic evolution. The patient consented to the procedure and publication of his image.

A case of facial nerve palsy caused by severe head injury treated by translabyrinthine approach.

Background: Several treatments for traumatic facial paralysis have been reported, but the role of surgery is still controversial. Case Description: A 57-year-old man was admitted to our hospital with head trauma due to a fall injury. A total body computed tomography (CT) scan showed a left frontal acute epidural hematoma associated with a left optic canal and petrous bone fractures with the disappearance of the light reflex. Hematoma removal and optic nerve decompression were performed immediately. The initial treatment was successful with complete recovery of consciousness and vision. The facial nerve paralysis (House and Brackmann scale grade 6) did not improve after medical therapy, and thus, surgical reconstruction was performed 3 months after the injury. The left hearing was lost entirely, and the facial nerve was surgically exposed from the internal auditory canal to the stylomastoid foramen through the translabyrinthine approach. The facial nerve's fracture line and damaged portion were recognized intraoperatively near the geniculate ganglion. The facial nerve was reconstructed using a greater auricular nerve graft. Functional recovery was observed at the 6-months follow-up (House and Brackmann grade 4), with significant recovery in the orbicularis oris muscle. Conclusion: Interventions tend to be delayed, but it is possible to select a treatment method of the translabyrinthine approach.

A case of anterior choroidal artery occlusion test under MEP monitoring for a recurrent internal carotid artery-anterior choroidal artery bifurcation aneurysm clipping.

A 59-year-old female with recurrent Anterior Choroidal Artery (AchA) aneurysm was elected for surgery at our institution through a standard pterional approach. Two thin perforating branches were found to origin from the dome of the aneurysm during operation, and therefore complete aneurysm clipping preserving these branches was not feasible. These perforating branches were temporarily occluded under motor-evoked potential (MEP) monitoring. The MEPs remained stable during 10 min of temporary clipping, and we concluded that these branches could be sacrificed, and therefore neck clipping was performed occluding these tiny AchA perforators. Although postoperative magnetic resonance imaging with diffusion-weighted images showed ischemic signs in left AchA territory after the operation, the patient remained asymptomatic and was discharged home with mRS 0.

Emergent Subarachnoid Clot Removal with Aneurysm Repair for Subarachnoid Hemorrhage Might Improves Clinical Outcome.

BACKGROUND: The goal in treating patients with subarachnoid hemorrhage (SAH) is shifting to preventing early brain injury. Intracranial pressure must be controlled to manage such an injury. We retrospectively analyzed the impact of aggressive removal of cisternal subarachnoid clots with simultaneous aneurysm repair for all grades of SAH. METHODS: Our study included 260 consecutive patients with SAH treated through aggressive subarachnoid clot removal with simultaneous aneurysm repair. Baseline patient characteristics, history, radiographic findings, and time of SAH onset to arrival in the operating room were retrospectively collected. Factors related to poor outcome (modified Rankin Scale score >2) were analyzed. RESULTS: Multivariate analysis revealed several characteristics were significantly associated with poor outcome: advanced age (adjusted odds ratio [aOR] 1.07, 95% confidence interval [CI] 1.04-01.10); time of SAH onset to operating room per 1-hour increments (aOR 1.03, 95% CI 1.01-01.05; postoperative hematoma volume (aOR 1.04, 95% CI 1.01-01.06); and poorer World Federation of Neurosurgical Societies grade (aOR 2.18, 95% CI 1.63-02.92). According to a receiver operating characteristic analysis, the cut-off time of SAH onset to operating room was 6.0 hours (area under the curve 0.61, P = 0.01, 95% CI 0.52-0.69, sensitivity = 0.79, specificity = 0.43) as the threshold between modified Rankin Scale scores of 0-2 and 3-6. CONCLUSIONS: Prognostic factors of SAH in patients undergoing emergent aneurysm repair with simultaneous removal of a cisternal subarachnoid clot are advanced age, poorer World Federation of Neurosurgical Societies grade, postoperative hematoma volume, and a longer time from SAH onset to operating room. The clinical outcome may improve with emergent reduction of intracranial pressure through removal of the subarachnoid clot as soon as possible.

[Primary leptomeningeal gliomatosis treated with temozolomide: a case report].

A 35-year-old man was admitted to our department for loss of consciousness. CT and MRI revealed diffuse enhancement of the subarachnoid space surrounding the brainstem and the cerebellar sulci, without any parenchymal lesions in the brain or the spinal cord. Furthermore, gadolinium-enhanced MRI revealed a nodular lesion with heterogeneous enhancement in the right prepontine cistern, at the site from which a biopsy was obtained via right lateral suboccipital craniotomy on the day following admission. Histopathological examination of the resected specimen revealed glioblastoma multiforme. Based on the radiological and histopathological findings, the patient was diagnosed with primary leptomeningeal gliomatosis (PLG). The patient received temozolomide chemotherapy with concurrent radiotherapy and showed radiological remission, 12 months after diagnosis. However, he developed local recurrence 6 months later and died 23 months after diagnosis. Autopsy findings showed tumor cell infiltration of the leptomeninges, as well as the brain and spinal parenchyma. PLG should be considered in the differential diagnosis in patients with diffuse leptomeningeal enhancement even without parenchymal lesions on radiological imaging. A surgical biopsy is recommended for prompt and accurate diagnosis in such cases.

[Ruptured Spinal Arteriovenous Malformation Mimicking Bacterial Meningitis:A Case Report].

A 23-year-old woman was referred to our hospital with progressive headache and back pain. Cerebrospinal fluid(CSF)analysis revealed hypoglycorrhachia and pleocytosis. However, imaging studies did not reveal evidence of subarachnoid hemorrhage(SAH), and she was diagnosed with bacterial meningitis. CSF analysis repeated after antibiotic treatment continued to show evidence of blood. Spinal SAH was suspected, and MRI revealed a spinal arteriovenous malformation(AVM). Spinal digital subtraction angiography revealed the nidus and a feeder aneurysm, which was implicated as the source of bleeding;therefore, she was diagnosed with spinal SAH secondary to spinal intramedullary AVM(SAVM). She underwent endovascular treatment for the spinal aneurysm and was discharged without worsening neurological symptoms. SAVMs presenting without neurological findings and/or evidence of bleeding on plain CT images are diagnostically challenging;notably, findings on CSF analysis could mimic those observed in cases of infectious disease. We should cite vascular diseases such as SAVM.

[A Case of Pediatric C1 Dysplasia with Ruptured Aneurysm in Collateral Plexiform Arterial Network].

A 3-year-old girl was admitted to our hospital with symptoms including headache, nausea, and vomiting. Head CT scan showed subarachnoid hemorrhage in the right carotid cistern. Digital subtraction angiography revealed right internal caortid artery(ICA)malformation at the C1 segment with collateral plexiform arterial network. The right ICA branched into posterior communicating artery and anterior choroidal artery(AChoA)and the ICA was decreased in caliber. The distal portion of the C1 segment of the ICA continued to the collateral plexiform arterial network, forming a saccular aneurysm. The plexiform arterial network connected to the right AChoA and the anterior communicating artery and continued to the distal portion of the right M1 segment. Right cervical carotid artery was normal. There was no transdural collateral flow from the right external carotid artery. Genetic analysis of a variant of RING finger protein 213 was negative. We diagnosed this patient with C1 dysplasia. We performed coil embolization for the aneurysm. The patient was discharged without any neurological deficit. Four months after the surgery, recurrence of the aneurysm was observed. We suspected that the aneurysm was formed due to hemodynamic mechanism and vulnerability of the collateral plexiform arterial network.

Microvascular Revascularization for Recurrent A1 Anterior Cerebral Artery Aneurysm Postendovascular Treatment: A Case Report and Review of the Literature.

The recurrence of aneurysms postcoil embolization is a common occurrence. Endovascular coiling has been noted to be more effective for small lesions rather than the giant aneurysms. A postembolization recurrent aneurysm is a difficult condition to manage. We present a case of a recurrent giant aneurysm of the anterior cerebral arteries (ACAs) first segment (A1). It was managed by superficial temporal artery to A3 segment of anterior cerebral artery bypass anastomotic revascularization plus distal A1- segment clipping. A literature review is presented for the management of giant A1 artery aneurysms.

Relationship between low response to clopidogrel and periprocedural ischemic events with coil embolization for intracranial aneurysms.

OBJECTIVES: Low response to antiplatelet drugs is one of the risk factors for ischemic events. We examined the influence of low response to clopidogrel on symptomatic ischemic events and new ischemic MRI lesions with endovascular intracranial aneurysmal coil embolization. MATERIALS AND METHODS: Between August 2010 and July 2013, 189 procedures in 181 consecutive patients who underwent endovascular coiling and received clopidogrel before treatment were investigated retrospectively. Platelet aggregation activity was examined by VerifyNow analysis. Low response to clopidogrel was defined as P2Y12 reaction units ≥230 in this study. Symptomatic ischemic complications within 30 days and postoperative new ischemic lesions on MRI-diffusion weighted imaging were evaluated. RESULTS: 66 of 189 (34.9%) cases were low responders to clopidogrel. Ischemic complications occurred in 2 of 66 (3.0%) low responders compared with 6 of 123 (4.9%) responders (p=0.72). A new high intensity spot larger than 5 mm was significantly more frequent in low responders (26 of 66; 39.4%) than in responders (26 of 121; 21.2%; p=0.01). On multivariate analysis, independent risk factors for larger new ischemic lesions were low response to clopidogrel, smokers, posterior location, and aneurysms with a larger neck. CONCLUSIONS: Low response to clopidogrel had little effect on clinical outcome although it increased asymptomatic large ischemic lesions in this cohort.

Endovascular intervention for acute cervical carotid artery occlusion.

BACKGROUND: Acute cervical carotid artery occlusion presents with a severe neurological deficit and is associated with unfavorable outcomes. In this study, the authors report their experience with patients having had acute ischemic stroke due to cervical carotid occlusion, who underwent endovascular intervention. METHOD: Sixteen acute cervical carotid occlusion patients (15 males and 1 female; mean age 67.7 years) were treated by endovascularly between January 2009 and November 2012. Clinical, procedural, and angiographic data were retrospectively evaluated. Successful intracranial recanalization was based on thrombolysis in cerebral infarction score of 2B-3. A favorable outcome was defined as a modified Rankin Scale score of 0-2 at 90 days. FINDINGS: The average score of National Institutes of Health Stroke Scale before treatment was 15.9. Ten of 16 patients (63 %) were associated with intracranial tandem occlusion. Ten (63 %) cases were caused by atherosclerotic, 4 (25 %) by atrial fibrillation (AF), and 2 (13 %) by dissection. Thirteen of 16 (81 %) achieved successful cervical recanalization and 7 of 16 (44 %) patients obtained sufficient cervical and intracranial perfusion. As a result, 5 of 16 (31 %) patients demonstrated favorable outcomes. Five of seven patients (71 %) with successful cervical and intracranial recanalization presented favorable outcomes. In contrast, none of the patients without cervical or intracranial recanalization presented favorable outcomes. Three of 6 (50 %) patients initially without intracranial occlusion showed favorable outcomes, but only 2 of 10 (20 %) patients associated with intracranial occlusion had favorable outcomes. On the aspect of etiology, in atherosclerotic cases, 4 of 10 (40 %) showed favorable outcomes. However, all four AF cases deteriorated into poor outcomes. CONCLUSIONS: This study demonstrated the feasibility of endovascular intervention for acute cervical carotid artery occlusion. Although treatment for tandem occlusion and AF cases is an issue that should be resolved, intervention must be encouraged. Successful cervical and intracranial revascularization will be essential for favorable outcomes.

A unique type of dural arteriovenous fistula at confluence of sinuses treated with endovascular embolization: a case report.

Dural arteriovenous fistula (DAVF) is classically defined as abnormal arteriovenous connections located within the dural leaflets. Though the exact etiology is still not clear, they are generally accepted as acquired lesions. However, some DAVFs formed as the congenital disorders are called dural arteriovenous malformations and these lesions with a marked cortical venous reflux are considered to be aggressive and warrant an early intervention. The authors describe a case of 35-year-old man presented with unique type of DAVF. The fistula was located adjacent to the confluence of venous sinuses with multiple feeders. The feeders drained into a large venous pouch just anterior to the confluence which had a bilateral venous drainage. This was associated with multiple cerebellar venous ectasia along the draining cortical vein. It was managed by staged endovascular procedures and complete cure could be achieved. The pathogenesis and technique of embolization of this complex fistula/malformation are also discussed.

Pial arteriovenous fistula as a cause of bilateral thalamic hyperintensities--an unusual case report and review of the literature.

INTRODUCTION: Isolated bilateral thalamic congestion due to an arteriovenous malformation (AVM) is a rare entity. Few case reports of dural arteriovenous fistula associated with it have been reported in the literature. The association of pial arteriovenous fistula (pial AVF) with thalamic hyperintensities has never been described before. The pial AVF is a recently recognized lesion in which the multiple pial arterial feeders drain into a single venous channel without a nidus like in conventional AVM. In spite of being congenital in origin, these lesions may have expression in adulthood due to abrupt change in the venous drainage system. Successful management of pial AVF associated with bilateral thalamic hyperintensities is described here with review of the literature. CASE PRESENTATION: A 60-year-old man presented with rapidly progressive gait disturbance and cognitive decline. Magnetic resonance imaging (MRI) showed hyperintensities in the thalami on T2-weighted and fluid attenuated inversion recovery image. Digital subtraction angiography revealed a pial AVF near the splenium of corpus callosum. It had feeders from posterior choroidal arteries and drained into the vein of Galen through an abnormal mesencephalic vein. The stagnation and increase of pressure in the deep venous system led to congestion in the thalami. He was treated by partial transarterial embolization of the feeders followed by gamma knife therapy (GKT). The clinical symptoms and MRI improved rapidly after embolization and further reduction in shunt flow was observed after GKT. CONCLUSION: Strong suspicion of vascular malformation as a cause of bilateral thalamic hyperintensities helps in early detection. Such lesions like pial AVF presented here require active intervention by surgery or endovascular therapy. GKT is an important adjuvant in lesions refractory to either of them.

[Resistance to antiplatelet agents assessed by a point-of-care platelet function test and thromboembolic adverse events in neurointervention].

OBJECTIVE: To clarify the frequency of Japanese patients who are resistant to antiplatelet agents, and then clarify correlations between resistance and thromboembolic adverse events in neurointervention. METHODS: Blood samples were collected from 163 patients who were taking antiplatelet agents and received neurointervention, with 128 samples collected just before neurointervention. Residual platelet function was measured using a point-of-care platelet function test, VerifyNow®, and then the frequency of patients resistant to drugs (low-responders), correlations between resistance and thromboembolic events, and effects of adding cilostazol to clopidogrel administration were analyzed. Cut-off values were defined as 550 Aspirin Reaction Units (ARU), 230 P2Y12 Reaction Units (PRU), and 50%inhibition of P2Y12, respectively. RESULTS: Three of 105 patients (2.9%) taking aspirin at 100 mg/day were low-responders, whereas 48 (41.0%, as measured by PRU) or 80 (68.4%, as measured by %inhibition) of 117 patients taking clopidogrel at 75 mg/day were low-responders. Among the 19 patients taking cilostazol 200 mg/day in addition to clopidogrel 75 mg/day, platelet functions were significantly more strongly inhibited compared to patients taking clopidogrel alone (p=0.02 by PRU, p=0.005 by %inhibition). Thromboembolic adverse events occurred in 7 patients. Among these 7 patients, 6 who were taking aspirin were all responders to aspirin, while 4 of the 6 patients taking clopidogrel were low-responders to clopidogrel. In 69 patients who received aneurysmal transarterial embolization, 2 thromboembolic complications occurred among low-responders (p=0.09). CONCLUSION: Aspirin resistance is rare in Japanese individuals. With aneurysmal transarterial embolization, thromboembolic events tended to occur among clopidogrel low-responders. Addition of cilostazol may offer one method of overcoming clopidogrel resistance.

Magnetic resonance fluid dynamics for intracranial aneurysms--comparison with computed fluid dynamics.

BACKGROUND: Hemodynamics in intracranial aneurysms is thought to play an important role in their growth and rupture. Usual computed fluid dynamics (CFD) based on three-dimensional (3D) computed tomographic (CT) angiography requires a time-consuming process for analysis. Magnetic resonance fluid dynamics (MRFD) based on MR images is a new tool for analyzing flow dynamics and a promising method for obtaining such information more easily. We compared the data from MRFD and CFD and studied the clinical feasibility of MRFD. METHODS: A total of 15 aneurysms, including two ruptured ones, in 15 patients were investigated with MR imaging and 3D-CT angiography. The flow data of MRFD and CFD, 3D stream lines, flow velocity profile and wall shear stress (WSS) were extracted from the image reconstruction and were compared each other. RESULTS: Both flow dynamics images showed quite similar 3D flow pattern and WSS map. However, the calculated value of maximum WSS was quite different and there was no significant correlation. Further, in one ruptured case, CFD showed less visualization to evaluate the intra-aneurysmal flow. Interestingly, one delayed rupture case showed a particular flow pattern with abnormal secondary flow in the bottom of the aneurysm before rupture, which might suggest the specific finding of rupture risk. CONCLUSION: MRFD is a valuable and less invasive tool to evaluate aneurysmal fluid dynamics. It can be obtained from the usual MRI examination without contrast medium and exposure to radiation. Although there is a problem of consistency of the absolute value of WSS between MRFD and conventional CFD, it may be useful to predict the risk of enlargement or rupture of aneurysms based on the information of the similar distribution of WSS and flow patterns. The quantifiable analysis and establishment of a meaningful threshold for high risk should be further studied.

Fenestration of a supraclinoid internal carotid artery associated with dual aneurysms: case report.

BACKGROUND AND IMPORTANCE: We present a rare case of fenestration of the left supraclinoid intracranial internal carotid artery with 2 associated aneurysms arising proximally and distally from the fenestration that were successfully treated with endovascular coil embolization. This is the first report of these types of aneurysms treated with coiling alone. CLINICAL PRESENTATION: A 47-year-old woman underwent a diagnostic workup; magnetic resonance angiography incidentally revealed 2 tandem aneurysms at the supraclinoid and paraclinoid portion of the left internal carotid artery. Angiography revealed fenestration of the left supraclinoid internal carotid artery with 2 aneurysms both proximal and distal to the fenestration. The patient underwent endovascular coil embolization of the aneurysms simultaneously. The smaller trunk was intentionally occluded to achieve complete packing of the proximal aneurysm. Both aneurysms were totally occluded, and no neurological deficits developed in the patient. CONCLUSION: Based on previous reports, fenestration has the potential to form an aneurysm, and there seemed to be a relatively high incidence of rupture if accompanied by aneurysm. Coiling is one good option to treat aneurysms and should be considered when multiple aneurysms exist because all aneurysms can be treated simultaneously. Proximal occlusion of the smaller trunk is acceptable because of a retrograde flow from the distal end, even if one exists.

Endovascular coil embolization for saccular-shaped blood blister-like aneurysms of the internal carotid artery.

BACKGROUND: Because of their fragile and thin wall, ruptured blood blister-like aneurysms (BBAs) at the anterior wall of the internal carotid artery (ICA) are difficult to manage, both surgically, as well as endovascularly. BBA is usually a tiny and broad-necked aneurysm, but it occasionally demonstrates a relatively saccular-like shape. In addition, the pseudoaneurysm sac often assumes a saccular shape. In this paper, the authors present their experience in treating these saccular-shaped BBAs endovascularly with coil packing. METHOD: Nine saccular-shaped ruptured BBAs in nine patients (one male and eight females; mean age 51.3 years, range 38-76) were treated with coil packing of the lesion between January 2006 and August 2010 in Nagoya University and its affiliated hospitals. Clinical, procedural, and angiographic data were retrospectively evaluated. FINDINGS: Seven BBAs were treated by balloon-assisted coil embolization. Two remaining BBAs were embolized without balloon inflation, though a balloon catheter was on standby at the ICA. In one case, in which a saccular coil embolization could not be achieved, ICA trapping was performed. Three (33.3%) were treated in acute, two (22.2%) in subacute, and four (44.4%) in chronic period. One (11.1%) intraoperative rupture occurred. Six (66.7%) had excellent clinical outcomes, while two (22.2%) proved fatal outcomes. During the follow-up period (mean 18.9 months, range 4-48), two out of seven (28.6%) aneurysms presented an angiographical recurrence, but both were treated by coil embolization without complications. The remaining five (71.4%) aneurysms were completely resolved. CONCLUSIONS: Endovascular coil embolization can be considered as an alternative treatment option for selective saccular-shaped BBAs.