Treatment of posterior circulation fusiform aneurysms.

OBJECTIVE: Perforator arteries, the absence of an aneurysm discrete neck, and the often-extensive nature of posterior circulation fusiform aneurysms present treatment challenges. There have been advances in microsurgical and endovascular approaches, including flow diversion, and the authors sought to review these treatments in a long-term series at their neurovascular referral center. METHODS: The authors performed a retrospective chart review from 1990 to 2018. Primary outcomes were modified Rankin Scale (mRS) scores and Glasgow Outcome Scale (GOS) scores at follow-up. The authors also examined neurological complication rates. Using regression techniques, they reviewed independent and dependent variables, including presenting features, aneurysm location and size, surgical approach, and pretreatment and posttreatment thrombosis. RESULTS: Eighty-four patients met the inclusion criteria. Their mean age was 53 years, and 49 (58%) were female. Forty-one (49%) patients presented with subarachnoid hemorrhage. Aneurysms were located on the vertebral artery (VA) or posterior inferior cerebellar artery (PICA) in 50 (60%) patients, basilar artery (BA) or vertebrobasilar junction (VBJ) in 22 (26%), and posterior cerebral artery (PCA) in 12 (14%). Thirty-one (37%) patients were treated with microsurgical and 53 (63%) with endovascular approaches. Six aneurysms were treated with endovascular flow diversion. The authors found moderate disability or better (mRS score ≤ 3) in 85% of the patients at a mean 14-month follow-up. The GOS score was ≥ 4 in 82% of the patients. The overall neurological complication rate was 12%. In the regression analysis, patients with VA or PICA aneurysms had better functional outcomes than the other groups (p < 0.001). Endovascular strategies were associated with better outcomes for BA-VBJ aneurysms (p < 0.01), but microsurgery was associated with better outcomes for VA-PICA and PCA aneurysms (p < 0.05). There were no other significant associations between patient, aneurysm characteristics, or treatment features and neurological complications (p > 0.05). Patients treated with flow diversion had more complications than those who underwent other endovascular and microsurgical strategies, but the difference was not significant in regression models. CONCLUSIONS: Posterior circulation fusiform aneurysms remain a challenging aneurysm subtype, but an interdisciplinary treatment approach can result in good outcomes. While flow diversion is a useful addition to the armamentarium, traditional endovascular and microsurgical techniques continue to offer effective options.

Clinical Course of Unilateral Moyamoya Disease.

BACKGROUND: The natural history of unilateral moyamoya disease (MMD) progressing to bilateral MMD remains an enigma in modern vascular neurosurgery. Few, small series with limited follow-up have reported relatively high rates of contralateral stenosis progression. OBJECTIVE: To review our large series of unilateral MMD patients and evaluate radiographic and surgical progression rates, and identify any factors associated with progression. METHODS: We included all unilateral MMD cases treated from 1991 to 2017 in an observational study. We examined time to contralateral radiographic progression and contralateral progression requiring surgery. Using Cox regression analysis, we evaluated factors potentially associated with contralateral progression. RESULTS: There were 217 patients treated for unilateral MMD. About 71% were female, and the average age at first surgery was 33.8 yr. Average follow-up was 5.8 yr (range 1-22 yr). A total of 18 patients (8.3%) developed contralateral progression. And 8 of these (3.7%) developed progression requiring bypass surgery. Baseline stenosis and hyperlipidemia (HLD) were significantly associated with radiographic progression (hazard ratio [HR] = 9.7, P = .006; HR = 4.0, P = .024). Baseline stenosis was associated with surgical progression (HR = 44.2, P = .002). Results were similar when controlling for possible confounders using multivariate regression. CONCLUSION: Previous series showed relatively high rates of progression in unilateral MMD (15%-30%), but these studies were small and long-term follow-up was rarely available. Our large series indicates that the rate of progression is lower than previously reported but still warrants yearly noninvasive screening. These data may provide indirect support for statin therapy in MMD.

Translamina Terminalis Approach to Laser-Assisted Resection of Thalamomesencephalic Cavernous Malformation.

Cavernous malformations of the midbrain require careful consideration of the risks and benefits of intervention as well as the optimal surgical approach for these challenging lesions. Excellent results can be achieved with careful surgical planning and technique. We demonstrate a contralateral left pterional craniotomy for a translamina terminalis approach to carbon dioxide laser-assisted microsurgical resection of a thalamomesencephalic cavernoma in a 59-year-old woman with progressive debilitating diplopia secondary to partial third nerve palsy (Video 1). We performed a contralateral left modified pterional craniotomy in which we limited dissection of the temporalis muscle to approximately one third rather than extending the muscle split down to the zygoma. The cavernous malformation was resected with no complications, and the patient was discharged from the hospital on postoperative day 3. She noted immediate improvement and nearly complete resolution of symptoms over ensuing weeks. This approach offers a direct route to the lesion with minimal brain transgression, while avoiding the critical structures within the interpeduncular cistern, including the basilar artery and thalamomesencephalic perforating arteries, as well as bordering neural structures, including cerebral peduncles, oculomotor nerves, and mamillary bodies. Use of the carbon dioxide laser with its 0.55-mm tip offers a low surgical profile and allows for precise cutting, thus minimizing thermal damage to surrounding tissues. The translamina terminalis approach through a pterional craniotomy offers a safe and potentially less morbid alternative to select thalamomesencephalic lesions compared with exposure through the mesencephalic surface, which in our experience often necessitates an orbitozygomatic craniotomy.

Contralateral Vasospasm in an Uncomplicated Elective Anterior Communicating Artery Aneurysm Clipping.

BACKGROUND: Cerebral vasospasm following clipping of an unruptured aneurysm is a rare phenomenon. When it does occur, cerebral vasospasm usually occurs on the side ipsilateral to the surgical intervention. CASE DESCRIPTION: A 68-year-old man underwent right-sided pterional craniotomy for clipping of an unruptured anterior communicating artery aneurysm and experienced contralateral vasospasm 5 days later. CONCLUSIONS: We further discuss the pathophysiology underlying vasospasm after uncomplicated craniotomy and nonhemorrhagic aneurysm clipping.

Pregnancy after direct cerebral bypass for moyamoya disease.

OBJECTIVE: Moyamoya disease (MMD) disproportionately affects young to middle-aged women. The main treatment for this challenging disease is cerebral bypass surgery. Vascular neurosurgeons often need to counsel women regarding pregnancy following bypass for MMD, but there is a paucity of data. The authors set out to examine neurological and obstetric outcomes in an extensive cohort of MMD patients who had pregnancies following cerebral revascularization at the Stanford Medical Center. METHODS: The authors identified all patients at their institution who underwent cerebral bypass for MMD from 1990 through 2018 and who later became pregnant. Some of these patients also had pregnancies prior to undergoing bypass surgery, and the authors examined these pregnancies as well. They performed a chart review and brief telephone survey to identify obstetric complications, transient ischemic attacks (TIAs), and strokes. Neurological and obstetric outcomes were compared to published rates. They also compared pre- and post-bypass pregnancy complication rates using logistic regression techniques. RESULTS: There were 71 pregnancies among 56 women whose mean age was 30.5 years. Among 59 post-bypass pregnancies, there were 5 (8%) perinatal TIAs. There were no MRI-confirmed strokes or strokes with residual deficits. Among 12 pre-bypass pregnancies, there were 3 (25%) TIAs and 2 (17%) MRI-confirmed strokes. There were no hemorrhagic complications in either group. In the generalized estimating equations analysis, performing cerebral revascularization prior to pregnancy versus after pregnancy was associated with lower odds of perinatal stroke or TIA (OR 0.15, p = 0.0061). Nine pregnancies (13%) were complicated by preeclampsia, and there was one (1%) instance of eclampsia. The overall rate of cesarean delivery was 39%. There were 2 miscarriages, both occurring in the first trimester. There were no maternal deaths. CONCLUSIONS: The authors present neurological and obstetric outcomes data in a large cohort of MMD patients. These data indicate that post-bypass pregnancy is accompanied by low complication rates. There were no ischemic or hemorrhagic strokes among post-bypass pregnant MMD patients. The rate of obstetric complications was low overall. The authors recommend close collaboration between the vascular neurosurgeon and the obstetrician regarding medical management, including blood pressure goals and continuation of low-dose aspirin.

Microsurgical rhizotomy for trigeminal neuralgia in MS patients: technique, patient satisfaction, and clinical outcomes.

OBJECTIVEPatients with multiple sclerosis (MS)-associated trigeminal neuralgia (TN) have higher recurrence and retreatment rates than non-MS patients. The optimal management strategy and role for microsurgical rhizotomy (MSR) for MS-TN remains to be determined. The aim of this study was to report time to treatment failure (TTF) and pain scores following MSR compared to percutaneous and Gamma Knife procedures.METHODSTime to treatment failure was analyzed after MSR (n = 14) versus prior procedures (n = 53) among MS-TN patients. Kaplan-Meier curves and log-rank test were utilized to compare TTF after MSR versus prior procedures using the same cohort of patients as their own control group. Subsequent analysis compared TTF after MSR to TTF after 93 other procedures among a second cohort of 18 MS-TN patients not undergoing MSR. BNI pain scores were compared between MSR and other procedures among the MS-TN cohort using a chi-square test.RESULTSTTF was significantly longer after MSR than after other procedures in the MSR cohort (median TTF 79 vs 10 months, respectively, p < 0.0001). Similarly, TTF was longer after MSR than after prior procedures in the non-MSR cohort (median TTF 79 vs 13 months, respectively, p < 0.001). MSR resulted in a higher proportion of excellent pain scores when compared to other procedures in the non-MSR cohort (77% vs 29%, p < 0.001). Probability of treatment survival was higher after MSR than after other procedures at all time points (3, 6, 12, 24, 36, and 48 months). There were no deaths or major complications after MSR.CONCLUSIONSTTF was significantly longer following MSR compared to prior procedures in MS-TN patients. Additionally, a higher proportion of patients achieved excellent BNI pain scores after MSR.

Trigeminal neuropathy associated with an enlarging arachnoid cyst in Meckel's cave: case report, management strategy and review of the literature.

We describe a rare case and novel management strategy of painful trigeminal neuropathy caused by an arachnoid cyst confined to Meckel's cave. A 57-year-old female presented with several years of progressive trigeminal pain and signs of trigeminal deafferentation, including sensory loss, corneal anesthesia and mastication muscle atrophy. Medical treatment with carbamazepine provided partial and temporary pain control. Surgical treatment was eventually performed by aspiration of the arachnoid cyst through the foramen ovale using a percutaneous approach. The patient experienced relief of pain and improvement of numbness and muscle strength. To our knowledge, this is the first case description of a percutaneous drainage of a Meckel's cave arachnoid cyst.