Microsurgical Resection of Brainstem Cavernous Malformations in Older Adults: A Multicenter, 30-Year Experience.

BACKGROUND AND OBJECTIVES: Microsurgical resection is the only curative intervention for symptomatic brainstem cavernous malformations (BSCMs), but the management of these lesions in older adults (≥65 years) is not well described. This study sought to address this gap by examining the safety and efficacy of BSCM resection in a cohort of older adults. METHODS: Records of patients who underwent BSCM resection over a 30-year period were reviewed retrospectively. Baseline characteristics and outcomes were compared between older (≥65 years) and younger (<65 years) patients. RESULTS: Of 550 patients with BSCM who met inclusion criteria, 41 (7.5%) were older than 65 years. Midbrain (43.9% vs 26.1%) and medullary lesions (19.5% vs 13.6%) were more common in the older cohort than in the younger cohort ( P = .01). Components of the Lawton BSCM grading system (ie, lesion size, crossing axial midpoint, developmental venous anomaly, and timing of hemorrhage) were not significantly different between cohorts ( P ≥ .11). Mean (SD) Elixhauser comorbidity score was significantly higher in older patients (1.86 [1.06]) than in younger patients (0.66 [0.95]; P < .001). Older patients were significantly more likely than younger patients to have poor outcomes at final follow-up (28.9% vs 13.8%, P = .01; mean follow-up duration, 28.7 [39.1] months). However, regarding relative neurological outcome (preoperative modified Rankin Scale to final modified Rankin Scale), rate of worsening was not significantly different between older and younger patients (23.7% vs 14.9%, P = .15). CONCLUSION: BSCMs can be safely resected in older patients, and when each patient's unique health status and life expectancy are taken into account, these patients can have outcomes similar to younger patients.

Sex differences in patients with and without high-risk factors associated with aneurysmal subarachnoid hemorrhage.

BACKGROUND: Controversy remains regarding the appropriate screening for intracranial aneurysms or for the treatment of aneurysmal subarachnoid hemorrhage (aSAH) for patients without known high-risk factors for rupture. This study aimed to assess how sex affects both aSAH presentation and outcomes for aSAH treatment. METHOD: A retrospective cohort study was conducted of all patients treated at a single institution for an aSAH during a 12-year period (August 1, 2007-July 31, 2019). An analysis of women with and without high-risk factors was performed, including a propensity adjustment for a poor neurologic outcome (modified Rankin Scale [mRS] score > 2) at follow-up. RESULTS: Data from 1014 patients were analyzed (69% [n = 703] women). Women were significantly older than men (mean ± SD, 56.6 ± 14.1 years vs 53.4 ± 14.2 years, p < 0.001). A significantly lower percentage of women than men had a history of tobacco use (36.6% [n = 257] vs 46% [n = 143], p = 0.005). A significantly higher percentage of women than men had no high-risk factors for aSAH (10% [n = 70] vs 5% [n = 16], p = 0.01). The percentage of women with an mRS score > 2 at the last follow-up was significantly lower among those without high-risk factors (34%, 24/70) versus those with high-risk factors (53%, 334/633) (p = 0.004). Subsequent propensity-adjusted analysis (adjusted for age, Hunt and Hess grade, and Fisher grade) found no statistically significant difference in the odds of a poor outcome for women with or without high-risk factors for aSAH (OR = 0.7, 95% CI = 0.4-1.2, p = 0.18). CONCLUSIONS: A higher percentage of women versus men with aSAH had no known high-risk factors for rupture, supporting more aggressive screening and management of women with unruptured aneurysms.

Vitamin D deficiency promotes intracranial aneurysm rupture.

Intracranial aneurysm rupture causes severe disability and high mortality. Epidemiological studies show a strong association between decreased vitamin D levels and an increase in aneurysm rupture. However, the causality and mechanism remain largely unknown. In this study, we tested whether vitamin D deficiency promotes aneurysm rupture and examined the underlying mechanism for the protective role of vitamin D against the development of aneurysm rupture utilizing a mouse model of intracranial aneurysm. Mice consuming a vitamin D-deficient diet had a higher rupture rate than mice with a regular diet. Vitamin D deficiency increased proinflammatory cytokines in the cerebral arteries. Concurrently, vitamin D receptor knockout mice had a higher rupture rate than the corresponding wild-type littermates. The vitamin D receptors on endothelial and vascular smooth muscle cells, but not on hematopoietic cells, mediated the effect of aneurysm rupture. Our results establish that vitamin D protects against the development of aneurysmal rupture through the vitamin D receptors on vascular endothelial and smooth muscle cells. Vitamin D supplementation may be a viable pharmacologic therapy for preventing aneurysm rupture.

Fenestrated Aneurysm Clip Trigeminal Decompression after CyberKnife Treatment Failure.

Objective This article describes a novel technique for trigeminal nerve decompression in the setting of refractory trigeminal neuralgia (TN). Design Technical note with an illustrative case example and operative video. Setting Outpatient, inpatient, and operating room of a quaternary neurosurgical referral center. Participant A woman in her early 70s who had previously undergone linear accelerator-based stereotactic radiotherapy (i.e., CyberKnife) and achieved 2 years of partial pain relief. However, facial pain, numbness, and parasympathetic dysfunction returned and became unbearable. Main Outcome Measure Durable relief of TN. Results Microvascular decompression was recommended for refractory TN. Intraoperatively, the trigeminal nerve was markedly attenuated from previous irradiation, with the superior cerebellar artery (SCA) loop embedded in the nerve at its root entry zone. The arterial loop was mobilized into a new position superior to the nerve, thus liberating it from the impingement. The tentorium was incised, and a fenestrated aneurysm clip was positioned such that the SCA loop was transmitted via the fenestration. The clip was applied across the tentorium, thus suspending the artery in a kink-free orientation that made no contact with the nerve. Conclusion This procedure provided excellent neurovascular decompression without placing mechanical strain on the nerve, relieving the patient's persistent postirradiation TN. The technique could have broader applications for other challenging or atypical microvascular decompression procedures.

A Review of Preoperative Embolization Effectiveness in Patients With Arteriovenous Malformations.

BACKGROUND AND OBJECTIVES: Preoperative embolization of arteriovenous malformations (AVMs) remains controversial. This study sought to analyze the cost-effectiveness of preoperative embolization of AVMs. METHODS: Patients who underwent AVM resection at a single institute (January 1, 2015-December 31, 2020) were analyzed. Patients with preoperative embolization (embolization cohort) were compared with those without preoperative embolization (nonembolization cohort). Cost-effectiveness score (CE) was the primary outcome of interest and was determined by dividing the total 1-year cost by effectiveness, which was derived from a validated preoperative to last follow-up change in the modified Rankin Scale utility score. A lower CE signifies a more cost-effective treatment strategy. RESULTS: Of 188 patients, 88 (47%) underwent preoperative embolization. The mean (SD) total cost was higher in the embolization group than in the nonembolization group ($117 594 [$102 295] vs $84 348 [$82 326]; P < .001). The mean (SD) CE was higher in the embolization cohort ($336 476 [$1 303 842]) than in the nonembolization cohort ($100 237 [$246 255]; P < .001). Among patients with Spetzler-Martin (SM) grade I and II AVMs, the mean (SD) CE was higher in the embolization (n = 40) than in the nonembolization (n = 72) cohort ($164 950 [$348 286] vs $69 021 [$114 938]; P = .004). Among patients with SM grade III AVMs, the mean (SD) CE was lower in the embolization (n = 33) than in the nonembolization (n = 25) cohort ($151 577 [$219 130] vs $189 195 [$446 335]; P = .006). The mean (SD) CE was not significantly different between cohorts among patients with higher-grade AVMs (embolization cohort [n = 3] vs nonembolization cohort [n = 15]: $503 639 [$776 492] vs $2 048 419 [$4 794 758]; P = .49). The mean CE for embolized SM grade III aneurysms was nonsignificant in the ruptured group; however, for the unruptured group, CE was significantly higher in the embolization cohort (n = 26; $160 871 [$240 535]) relative to the nonembolization cohort (n = 15; $108 152 [$166 446]) ( P = .006). CONCLUSION: Preoperative embolization was cost-effective for patients with SM grade III AVMs but not for patients with lower-grade AVMs.

Early Treatment of Ruptured Cerebral Arteriovenous Malformations: Analysis of Neurological Outcomes and Health Care Costs.

BACKGROUND: The timing of surgical resection is controversial when managing ruptured arteriovenous malformations (AVMs) and varies considerably among centers. OBJECTIVE: To retrospectively analyze clinical outcomes and hospital costs associated with delayed treatment in a ruptured cerebral AVM patient cohort. METHODS: Patients undergoing surgical treatment for a ruptured cerebral AVM (January 1, 2015-December 31, 2020) were retrospectively analyzed. Patients who underwent emergent treatment of a ruptured AVM because of acute herniation were excluded, as were those treated >180 days after rupture. Patients were stratified by the timing of surgical intervention relative to AVM rupture into early (postbleed days 1-20) and delayed (postbleed days 21-180) treatment cohorts. RESULTS: Eighty-seven patients were identified. The early treatment cohort comprised 75 (86%) patients. The mean (SD) length of time between AVM rupture and surgical resection was 5 (5) days in the early cohort and 73 (60) days in the delayed cohort ( P < .001). The cohorts did not differ with respect to patient demographics, AVM size, Spetzler-Martin grade, frequency of preoperative embolization, or severity of clinical presentation ( P ≥ .15). Follow-up neurological status was equivalent between the cohorts ( P = .65). The associated mean health care costs were higher in the delayed treatment cohort ($241 597 [$99 363]) than in the early treatment cohort ($133 989 [$110 947]) ( P = .02). After adjustment for length of stay, each day of delayed treatment increased cost by a mean of $2465 (95% CI = $967-$3964, P = .002). CONCLUSION: Early treatment of ruptured AVMs was associated with significantly lower health care costs than delayed treatment, but surgical and neurological outcomes were equivalent.

Occipital Artery to Middle Cerebral Artery Direct Bypass: A Salvage Revascularization Technique for Ischemic Moyamoya Disease.

OBJECTIVE: The main treatment for moyamoya disease (MMD) is revascularization surgery. Most bypasses use the superficial temporal artery (STA) as the donor vessel. However, even if the STA-middle cerebral artery (MCA) bypass is functioning, the affected hemisphere can continue to be symptomatically malperfused. We sought to assess the efficacy of salvage direct revascularization surgery using the occipital artery (OA) as a donor vessel in patients with ischemic MMD who experience continued cerebral malperfusion despite previous successful STA-MCA bypass. METHODS: We retrospectively analyzed the cerebrovascular databases of 2 surgeons and described patients in whom the OA was used as the donor vessel for direct revascularization. RESULTS: Seven patients were included (5 women). Previous STA-MCA bypasses were direct (n = 2), indirect (n = 3), or combined/multiple (n = 2). The mean (SD) interval between STA-MCA and OA-MCA procedures was 29.2 (13.1) months. Despite an intact STA-MCA bypass in all 7 cases, all 7 patients had recurrent symptoms and demonstrated residual impaired cerebral perfusion. All 7 patients underwent successful OA-MCA direct revascularization. Follow-up perfusion imaging was obtained for 6 of 7 patients. All 6 of these patients demonstrated improved cerebral blood flow to the revascularized hemispheres. All 7 patients demonstrated clinical improvement. CONCLUSIONS: Patients with ischemic MMD who have continued symptoms and cerebral malperfusion despite previous successful STA-MCA bypass present a challenging clinical scenario. Our series highlights the potential utility of the OA-MCA direct bypass as a salvage therapy for these patients.

Mechanical disorders of the cervicocerebral circulation in children and young adults.

Mechanical disorders of the cervicocerebral circulation (MDCC) are conditions in which neurological symptoms result from a disturbance of cerebral blood flow attributable to external mechanical forces exerted on extracranial blood vessels by adjacent musculoskeletal structures during head movement that is presumably within a physiological range. The disease spectrum includes bow hunter's syndrome, carotid-type Eagle syndrome, and various dynamic venous compression syndromes. These conditions have distinct phenotypes in children which differ from those expressed in older adults. In contemporary practice, recognition and diagnostic evaluation is the domain of the neuroendovascular specialist. The diagnostic evaluation of MDCC involves significant technical nuance that can be critical to directing appropriate management, particularly in children. This report aims to provide a comprehensive overview of the pathophysiology, anatomical patterns, diagnosis, and treatment for the full spectrum of MDCC that is commonly encountered in clinical practice.

Retained radial catheters associated with variant radial anatomy in neurointerventional procedures.

BACKGROUND: Transradial artery access (TRA) for neurointerventional procedures is gaining widespread acceptance. However, complications that were previously rare may arise as TRA procedures increase. Here we report a series of retained catheter cases with a literature review. METHODS: All patients who underwent a neurointerventional procedure during a 23-month period at a single institution were retrospectively reviewed for a retained catheter in TRA cases. In cases of retained catheters, imaging was reviewed for anatomical variances in the radial artery, and clinical and demographic case details were analyzed. RESULTS: A total of 1386 nondiagnostic neurointerventional procedures were performed during the study period, 631 (46%) initially via TRA. The 631 TRA cases were performed for aneurysm embolization (n=221, 35%), mechanical thrombectomy (n=116, 18%), carotid stent/angioplasty (n=40, 6%), arteriovenous malformation embolization (n=38, 6%), and other reasons (n=216, 34%). Thirty-nine (6%) TRA procedures crossed over to femoral access, most commonly because the artery of interest could not be catheterized (26/39, 67%). A retained catheter was identified in five cases (1%), and one (0.2%) patient had an entrapped catheter that was recovered. All six patients with a retained or entrapped catheter had aberrant radial anatomy. CONCLUSION: Retained catheters for neurointerventional procedures performed via TRA are rare. However, this complication may be associated with variant radial anatomy. With the increased use of TRA for neurointerventional procedures, awareness of anatomical abnormalities that may lead to a retained catheter is necessary. We propose a simple protocol to avoid catheter entrapment, including in emergent situations such as TRA for stroke thrombectomy.

Direct puncture of the superior ophthalmic vein for carotid cavernous fistulas: a 21-year experience.

BACKGROUND: Direct puncture of the superior ophthalmic vein (SOV) is an alternative approach to traversing the inferior petrosal sinus for embolization of carotid cavernous fistulas (CCFs). OBJECTIVE: To analyze direct SOV puncture for the treatment of CCFs and review the literature. METHODS: All patients at a single center, treated for a CCF with direct SOV cannulation between January 1, 2000, and December 31, 2020, were retrospectively analyzed. An additional review of the literature for all case series for direct puncture of the SOV for treatment of CCF was performed. RESULTS: During the 21-year study period, direct cannulation of the SOV for treatment of a CCF was attempted for 19 patients, with the procedure aborted for one patient because of an inability to navigate the wire into the distal aspect of the cavernous sinus. In 18 patients with direct SOV CCF treatment, 1 experienced a minor complication with an asymptomatic postoperative hemorrhage. Angiographic cure and improvement of symptoms were achieved in 17 patients with a mean (SD) follow-up of 6 (5.2) months. In the review of the literature, an additional 45 patients were reported to have direct cannulation of the SOV for CCF treatment, with angiographic cure in 43 (96%) and decreased objective visual acuity in 1 (2%). CONCLUSION: Direct SOV cannulation to treat CCFs is safe and effective. Although it is typically used after other endovascular approaches have failed, SOV access for CCF treatment may be warranted as a first-line treatment for select patients.

Resection of Quadrigeminal Midbrain Cavernous Malformation Using the Supracollicular Safe Entry Zone.

Brainstem cavernous malformations (BSCMs) are rare and challenging neurosurgical lesions that demand a sophisticated and nuanced strategy for resection. A key element of surgical planning for BSCM resection is brainstem safe entry zones, a set of neuroanatomically defined locations where a pial resection can be executed with minimal risk to the adjacent central nervous system tracts and nuclei.1-5 Quadrigeminal BSCMs are particularly unusual and can be accessed via the supra-, inter-, or infracollicular safe entry zones.2,4,5 We report a unique demonstration of the supracollicular safe entry zone for the resection of a symptomatic hemorrhagic quadrigeminal plate BSCM. A man in his early 60s presented with transient hearing loss and visual dysfunction. A right quadrigeminal midbrain cavernous malformation was identified on magnetic resonance imaging. Surgical resection was performed with the patient in the sitting position. A bipedicular suboccipital flap, torcular craniotomy, and midline supracerebellar infratentorial approach were used. The lesion itself was accessed via the supracollicular safe entry zone, where pial hemosiderin staining was also encountered, using a linear transverse incision just above the right superior colliculus. Gross total resection was achieved, and the patient recovered from surgery with no new neurologic deficits (Video 1).

Incidence and Prediction of Chronic Depression Following Aneurysmal Subarachnoid Hemorrhage: A Single-Center 17-Year Experience.

OBJECTIVE: The incidence and risk factors for chronic depression after aneurysmal subarachnoid hemorrhage (aSAH) are described. METHODS: Patients with aSAH treated at a single institution (January 1, 2003-December 31, 2019) and a modified Rankin Scale score ≤3 at follow-up who were evaluated for chronic depression were analyzed. Chronic depression was defined using a depression screening questionnaire as ≥5 positive answers for symptoms lasting >2 weeks. A predictive model was designed for the primary outcome of depression. RESULTS: Among 1419 patients with aSAH, 460 patients were analyzed; 130 (28%) had major depressive disorder. Mean follow-up was >6 years. Higher depression rates were associated with tobacco smoking (odds ratio [OR] = 2.64, P < 0.001), illicit drug use (OR = 2.35, P = 0.007), alcohol use disorder (1.92, P = 0.04), chronic obstructive pulmonary disease (COPD) (OR=2.68, P = 0.03), and vasospasm requiring angioplasty (OR=2.09, P = 0.048). The predictive model included tobacco smoking, illicit drug use, liver disease, COPD, diabetes, nonsaccular aneurysm type, anterior communicating artery or anterior cerebral artery aneurysm location, refractory spasm requiring angioplasty, and a modified Rankin Scale score at discharge of >1 (P ≤ 0.03). The model performed with appropriate goodness of fit and an area under the receiver operator curve of 0.70 for depression. Individual independent predictors of depression were tobacco smoking, COPD, diabetes, and nonsaccular aneurysm. CONCLUSIONS: A substantial percentage of patients had symptoms of depression on follow-up. The proposed predictive model for depression may be a useful clinical tool to identify patients at high risk for developing depression who warrant early screening and evaluation.

Republished: Resolution of an enlarging subdural haematoma after contralateral middle meningeal artery embolisation.

A man in his 50s presented 1 month after an automobile accident with worsening headaches and an enlarging chronic left subdural haematoma (SDH). He underwent left middle meningeal artery (MMA) embolisation. Due to tortuosity at its origin, we were unable to catheterise the MMA distally. Only proximal coil occlusion at the origin was performed. Follow-up interval head CT showed an increase in the size of the SDH with new haemorrhage, worsening mass effect and midline shift. However, he remained neurologically intact. Contralateral embolisation of the right MMA was performed with a liquid embolic agent. His headaches improved, and a follow-up head CT 3 months later showed near-complete resolution of the SDH.

Microsurgical Treatment of Cerebral Aneurysms.

Despite advances in endovascular techniques, microsurgery continues to play an important role in the treatment of cerebral aneurysms. This article reviews the history of surgical treatment of intracranial aneurysms and the evolving role of microsurgery in the endovascular era. Although endovascular tools and techniques have changed significantly since the placement of the first Guglielmi coils in 1990, with the development of endoluminal flow-diverting stents and now endosaccular flow-diverting devices, microsurgical treatment of aneurysms has also continued to evolve. Since the first treatment with Hunterian ligation by Horsley in the 1800s, surgical treatment of intracranial aneurysms has advanced significantly beginning with the introduction of the microscope and microsurgical techniques in the 1950s. More recent advances in microsurgical treatment of aneurysms include microsurgical adjuncts, such as indocyanine green angiography, adenosine, and the exoscope, as well as tailored craniotomies, retractorless surgery, and novel bypass constructs for complex aneurysms. Microsurgery continues to play an important role in the endovascular era.

Effects of Preoperative Embolization on Spetzler-Martin Grade I and II Arteriovenous Malformations: A Propensity-Adjusted Analysis.

BACKGROUND: Cerebral arteriovenous malformations (AVMs) with low Spetzler-Martin grades (I and II) are associated with good neurological outcomes after microsurgical resection; however, the use of preoperative embolization for these lesions is controversial. OBJECTIVE: To compare the neurological outcomes of preoperative embolization with no embolization in patients with low-grade AVMs. METHODS: Patients with a Spetzler-Martin grade I or II AVM who underwent microsurgical resection during January 1, 1997, through December 31, 2019, were analyzed. Patients undergoing preoperative embolization were compared with patients not undergoing embolization. A propensity score was constructed from baseline characteristics and used to match intervention (embolization) and control (nonembolization) groups in a 1:1 ratio. The primary outcome was poor neurological status on last follow-up examination, defined as a modified Rankin Scale score >2 and a modified Rankin Scale score worse at follow-up than at the preoperative examination. RESULTS: Of the 603 patients analyzed, 310 (51.4%) underwent preoperative embolization and 293 (48.6%) did not. Patients in the embolization cohort compared with those in the nonembolization cohort had a higher percentage of Spetzler-Martin grade II AVMs (71.6% vs 52.6%, P < .001) and a lower percentage of hemorrhage (41% vs 55%, P = .001). After propensity score matching, no differences were found between paired cohorts (each N = 203) for baseline characteristics with a significant reduction in absolute standardized mean differences. No significant differences were found in primary outcomes between treatment groups in the matched or unmatched cohorts. CONCLUSION: Preoperative embolization of low-grade Spetzler-Martin AVMs is not associated with improved neurological outcomes after microsurgical resection.

Total 1-year hospital cost of middle meningeal artery embolization compared to surgery for chronic subdural hematomas: a propensity-adjusted analysis.

BACKGROUND: Middle meningeal artery (MMA) embolization results in fewer treatment failures than surgical evacuation for chronic subdural hematomas (cSDHs). We compared the total 1-year hospital cost for MMA embolization versus surgical evacuation for patients with cSDH. METHODS: Data for patients who presented with cSDHs from January 1, 2018, through May 31, 2020, were retrospectively reviewed. Patients were grouped by initial treatment (surgery vs MMA embolization), and total hospital cost was obtained. A propensity-adjusted analysis was performed. The primary outcome was difference in mean hospital cost between treatments. RESULTS: Of 170 patients, 48 (28%) underwent embolization and 122 (72%) underwent surgery. cSDHs were larger in the surgical (20.5 (6.7) mm) than in the embolization group (16.9 (4.6) mm; P<0.001); and index hospital length of stay was longer in the surgical group (9.8 (7.0) days) than in the embolization group (5.7 (2.4) days; P<0.001). More patients required additional hematoma treatment in the surgical cohort (16%) than in the embolization cohort (4%; P=0.03), and more required readmission in the surgical cohort (28%) than in the embolization cohort (13%; P=0.04). After propensity adjustment, MMA embolization was associated with a lower total hospital cost compared to surgery (mean difference -$32 776; 95% CI -$52 766 to -$12 787; P<0.001). A propensity-adjusted linear regression analysis found that unexpected additional treatment was the only significant contributor to total hospital cost (mean difference $96 357; 95% CI $73 886 to $118 827; P<0.001). CONCLUSIONS: MMA embolization is associated with decreased total hospital cost compared with surgery for cSDHs. This lower cost is directly related to the decreased need for additional treatment interventions.

Contralateral Supracerebellar-Transtentorial Approach for Posterior Mediobasal Temporal Cavernous Malformation Resection.

Cerebral cavernous malformations are abnormal clusters of thin-walled sinusoidal vascular channels without intervening brain parenchyma. The most common presenting symptom is seizure, which results from hemosiderin deposition in surrounding tissues. Early surgical resection of these malformations confers the greatest likelihood of long-term seizure freedom. This operative video demonstrates the resection of a posterior mediobasal temporal cavernous malformation through a contralateral supracerebellar-transtentorial (cSCTT) approach. The patient, a 65-year-old woman, presented with a complex partial seizure with secondary generalization. On preoperative evaluation, she was neurologically intact. The risks and benefits of treatment alternatives, including observation, were explained to her. She consented to proceed with surgery to remove the cavernous malformation. The patient was placed in the sitting position with neck flexion to flatten the angle of the tentorium. A torcular craniotomy was performed to expose the confluence of the sagittal and transverse sinuses. Gravity retraction of the cerebellum plus contralateral supracerebellar arachnoid dissection allowed generous exposure of the ambient cistern and incisura with no brain retraction or transgression. The tentorium was opened, and the cavernous malformation was then circumferentially dissected and removed en bloc. Postoperative magnetic resonance imaging findings indicated complete resection without cortical injury. The patient remained free of seizures through the 6-month follow-up. Video 1 demonstrates the cSCTT approach to lesions of the posterior mediobasal temporal lobe without the need for retraction or transcortical dissection. The cSCTT approach extends the reach of the ipsilateral, infratentorial approach laterally, which is nearly 2 cm off midline, more than is possible without cutting the tentorium.

Endovascular treatment of vertebral artery dissecting aneurysms : a 20-year institutional experience.

BACKGROUND: The ideal treatment for unruptured vertebral artery dissecting aneurysms (VADAs) and ruptured dominant VADAs remains controversial. We report our experience in the management and endovascular treatment of patients with VADAs. METHODS: Patients treated endovascularly for intradural VADAs at a single institution from January 1, 1999, to December 31, 2019, were retrospectively reviewed. Primary neurological outcomes were assessed using modified Rankin Scale (mRS) scores, with mRS >2 considered a poor neurological outcome. Additionally, any worsening (increase) in the mRS score from the preoperative neurological examination was considered a poor outcome. RESULTS: Ninety-one patients of mean (SD) age 53 (11.6) years (48 (53%) men) underwent endovascular treatment for VADAs. Fifty-four patients (59%) presented with ruptured VADAs and 44 VADAs (48%) involved the dominant vertebral artery. Forty-seven patients (51%) were treated with vessel sacrifice of the parent artery, 29 (32%) with flow diversion devices (FDDs), and 15 (17%) with stent-assisted coil embolization (stent/coil). Rates of procedural complications and retreatment were significantly higher with stent/coil treatment (complications 4/15; retreatment 6/15) than with vessel sacrifice (complications 1/47; retreatment 2/47) or FDD (complications 2/29; retreatment 4/29) (p=0.008 and p=0.002, respectively). Of 37 patients with unruptured VADAs treated, only two (5%) had mRS scores >2 on follow-up. CONCLUSION: Endovascular FDD treatment of VADAs appears to be associated with lower retreatment and complication rates than stenting/coiling, although further study is required for confirmation. Endovascular treatment of unruptured VADAs was safe and was associated with favorable angiographic and neurological outcomes.