Faculty Bibliography

BACKGROUND:Patients with aneurysmal subarachnoid hemorrhage (aSAH) frequently suffer from vasospasm. We analyzed the association between absence of early angiographic vasospasm and early discharge. METHODS:All aSAH patients treated from August 1, 2007, to July 31, 2019, at a single tertiary center were reviewed. Patients undergoing diagnostic digital subtraction angiography (DSA) on post-aSAH days 5 to 7 were analyzed; cohorts with and without angiographic vasospasm (angiographic reports by attending neurovascular surgeons) were compared. Primary outcome was hospital length of stay; secondary outcomes were intensive care unit length of stay, 30 day return to the emergency department (ED), and poor neurologic outcome, defined as a modified Rankin Scale (mRS) score >2. RESULTS:A total of 298 patients underwent DSA on post-aSAH day 5, 6, or 7. Most patients (n=188, 63%) had angiographic vasospasm; 110 patients (37%) did not. Patients without vasospasm had a significantly lower mean length of hospital stay than vasospasm patients (18.0±7.1 days vs 22.4±8.6 days; p<0.001). The two cohorts did not differ significantly in the proportion of patients with mRS scores >2 at last follow-up or those returning to the ED before 30 days. After adjustment for Hunt and Hess scores, Fisher grade, admission Glasgow Coma Scale score, and age, logistic regression analysis showed that the absence of vasospasm on post-aSAH days 5-7 predicted discharge on or before hospital day 14 (OR 3.4, 95% CI 1.8 to 6.4, p<0.001). CONCLUSION/CONCLUSIONS:Lack of angiographic vasospasm 5 to 7 days after aSAH is associated with shorter hospitalization, with no increase in 30 day ED visits or poor neurologic outcome.

BACKGROUND:levels and adverse cardiovascular outcomes in patients treated with drug-eluting stents. However, omeprazole use among patients treated with flow-diverting stents for intracranial aneurysms has not been evaluated. METHODS:levels, and thorough documentation of administration of other medications, including omeprazole. RESULTS:level >180 PRU in the omeprazole cohort (14 of 16 [88%] vs 24 of 122 [20%]; P<0.001; OR [95% CI], 29 [6-134]). CONCLUSION/CONCLUSIONS:reactivity level among patients with intracranial aneurysms treated with flow-diverting devices who received clopidogrel. However, receipt of omeprazole was not associated with an increased risk of ischemic events or stent stenosis. For neuroendovascular patients who are treated with a flow diverter while receiving clopidogrel, alternative gastrointestinal medication regimens should be considered.

BACKGROUND:Transradial access (TRA) for neuroendovascular procedures is increasing in prevalence. The safety benefits of TRA at a patient level may be offset at a population level by a paradoxical increase in transfemoral access (TFA) vascular access site complications (VASCs), the so-called "radial paradox." OBJECTIVE:To study the effect of TRA adoption on TFA performance and outcomes in neuroendovascular procedures. METHODS:Data were collected for all procedures performed over a 10-mo period after radial adoption at a single center. RESULTS:Over the study period, 1084 procedures were performed, including 719 (66.3%) with an intent to treat by TRA and 365 (33.7%) with an intent to treat by TFA. Thirty-two cases (4.4%) crossed over from TRA to TFA, and 2 cases (0.5%) crossed over from TFA to TRA. TFA was performed in older patients (mean [standard deviation] TFA, 63 [15] vs TRA, 56 [16] years) using larger sheath sizes (≥7 French; TFA, 56.2% vs TRA, 2.3%) ( P < .001 for both comparisons). Overall, 29 VASCs occurred (2.7%), including 27 minor (TFA, 4.6% [18/395] vs TRA, 1.3% [9/689], P = .002) and 2 major (TFA, 0.3% [1/395] vs TRA, 0.1% [1/689], P > .99) complications. Independent predictors of VASC included TFA (OR 2.8, 95% confidence interval [CI] 1.1-7.4) and use of dual antiplatelet therapy (OR 4.2, 95% CI 1.6-11.1). CONCLUSION:TFA remains an important access route, despite a predominantly radial paradigm, and is disproportionately used in patients at increased risk for VASCs. TFA proficiency may still be achieved in predominantly radial practices without an increase in femoral complications.

BACKGROUND:The middle meningeal artery (MMA) has been implicated in chronic headaches, but no studies have examined the relationship between MMA embolization and headaches. METHODS:Patients treated with MMA embolization for a chronic subdural hematoma (cSDH) between January 1, 2018, and December 31, 2020, were retrospectively assessed. Patients with a Glasgow Coma Scale (GCS) score of 15 at discharge received a follow-up telephone call to assess their history of chronic headache, defined as a headache ≥2 years before the cSDH and symptoms ≥2 days/month. A Headache Impact Test (HIT-6) was performed during the follow-up telephone call. The primary outcome was resolution or improvement of headaches after embolization. RESULTS:Of 76 patients undergoing MMA embolization for a cSDH during the study period, 56 (74%) had a discharge GCS score of 15. Of these 56 patients, 46 (82%) responded to a follow-up telephone call and were analyzed (mean [SD] age 68 [11] years; 36 [78%] men and 10 [22%] women). Nine (20%) reported chronic headaches before embolization. With a mean (SD) follow-up of 489 (173) days, eight of the nine patients reported improvement of chronic headaches, with seven having complete resolution. For these nine patients, the mean (SD) HIT-6 score was significantly higher before embolization than after embolization (64 [7.1] vs 40 [9.1], p<0.001). CONCLUSION/CONCLUSIONS:In patients with chronic headaches who underwent MMA embolization for a cSDH, the majority reported improvement of headaches after the procedure. Future prospective studies are warranted to assess the usefulness of MMA embolization to treat chronic headaches.

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.

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/CONCLUSIONS: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.

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.

BACKGROUND:The coronavirus disease 2019 pandemic necessitated the use of telemedicine for most medical specialties, including neurosurgery, although before the pandemic, neurosurgeons infrequently used telemedicine for outpatient visits. We conducted a patient-centric evaluation of telemedicine in our endovascular neurosurgery practice, covering a 4-month period early in the pandemic. METHODS:Survey e-mails after telemedicine visits were sent to all patients who underwent an outpatient telemedicine visit between March 11, 2020, and June 22, 2020, at an endovascular neurosurgery clinic affiliated with a tertiary care center. RESULTS:Of 140 patients, 65 (46%) completed the e-mail survey. Of the 65 respondents, 35 (54%) agreed or strongly agreed with the statement that even before their telemedicine experience, they thought telemedicine would be a convenient way to receive a neurological consultation. After their telemedicine visit, 47 (72%) agreed or strongly agreed with this statement, and 28 (43%) agreed or strongly agreed that they would prefer telemedicine for future visits. Of the 65 respondents, 61 (94%) rated their telemedicine visit as average or better: 34 (52%) rated it excellent, 12 (18%) rated it above average, and 15 (23%) rated it average. When patients compared their telemedicine visit with a prior in-person clinic visit, only 10 of 44 patients (23%) thought the telemedicine visit was more complicated than an in-person visit, and 21 of 44 (48%) said they would prefer telemedicine for future visits. CONCLUSIONS:Our patients expressed satisfaction with their telemedicine visits, and telemedicine will likely play an important role in future outpatient endovascular neurosurgery consultations.

OBJECTIVE:Supplemented Spetzler-Martin grading (Supp-SM), which is the combination of Spetzler-Martin and Lawton-Young grades, was validated as being more accurate than stand-alone Spetzler-Martin grading, but an operability cutoff was not established. In this study, the authors surgically treated intermediate-grade AVMs to provide prognostic factors for neurological outcomes and to define AVMs at the boundary of operability. METHODS:Surgically treated Supp-SM intermediate-grade (5, 6, and 7) AVMs were analyzed from 2011 to 2018 at two medical centers. Worsened neurological outcomes were defined as increased modified Rankin Scale (mRS) scores on postoperative examinations. A second analysis of 2000-2011 data for Supp-SM grade 6 and 7 AVMs was performed to determine the subtypes with improved or unchanged outcomes. Patients were separated into three groups based on nidus size (S1: < 3 cm, S2: 3-6 cm, S3: > 6 cm) and age (A1: < 20 years, A2: 20-40 years, A3: > 40 years), followed by any combination of the combined supplemented grade: low risk (S1A1, S1A2, S2A1), intermediate risk (S2A2, S1A3, S3A1, or high risk (S3A3, S3A2, S2A3). RESULTS:Two hundred forty-six patients had intermediate Supp-SM grade AVMs. Of these patients, 102 had Supp-SM grade 5 (41.5%), 99 had Supp-SM grade 6 (40.2%), and 45 had Supp-SM grade 7 (18.3%). Significant differences in the proportions of patients with worse mRS scores at follow-up were found between the groups, with 24.5% (25/102) of patients in Supp-SM grade 5, 29.3% (29/99) in Supp-SM grade 6, and 57.8% (26/45) in Supp-SM grade 7 (p < 0.001). Patients with Supp-SM grade 7 AVMs had significantly increased odds of worse postoperative mRS scores (p < 0.001; OR 3.7, 95% CI 1.9-7.3). In the expanded cohort of 349 Supp-SM grade 6 AVM patients, a significantly higher proportion of older patients with larger Supp-SM grade 6 AVMs (grade 6+, 38.6%) had neurological deterioration than the others with Supp-SM grade 6 AVMs (22.9%, p = 0.02). Conversely, in an expanded cohort of 197 Supp-SM grade 7 AVM patients, a significantly lower proportion of younger patients with smaller Supp-SM grade 7 AVMs (grade 7-, 19%) had neurological deterioration than the others with Supp-SM grade 7 AVMs (44.9%, p = 0.01). CONCLUSIONS:Patients with Supp-SM grade 7 AVMs are at increased risk of worse postoperative neurological outcomes, making Supp-SM grade 6 an appropriate operability cutoff. However, young patients with small niduses in the low-risk Supp-SM grade 7 group (grade 7-) have favorable postoperative outcomes. Outcomes in Supp-SM grade 7 patients did not improve with surgeon experience, indicating that the operability boundary is a hard limit reflecting the complexity of high-grade AVMs.