Nationwide trends in intensive care unit utilization in the elective endovascular treatment of unruptured intracranial aneurysms.

OBJECTIVE: Multiple studies suggest routine post-operative intensive care unit (ICU) stays after endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs) is unnecessary, though rates of ICU utilization nationwide are unknown. We aim to evaluate rates and characteristics of ICU utilization in patients undergoing elective endovascular repair of UIAs. METHODS: This is a retrospective cohort study utilizing a nationwide private-payer database in the United States to evaluate the ICU utilization in patients undergoing elective endovascular repair of UIAs between 2005 and 2019. Demographics and pre-operative comorbidities as well as post-procedural complications and discharge status were compared. An analysis of charges and costs was also performed. RESULTS: Among 6218 patients who underwent elective EVT of a UIA, 4890 (78.6%) were admitted to the ICU post-operatively. There were no differences in age, sex, or Charlson comorbidity scores in patients admitted to the ICU post-operatively compared to those admitted elsewhere. ICU utilization was more common in urban locations compared to rural. 12.7% of patients had ICU-specific needs sufficient to be billed by a critical care provider. Total provider costs were significantly higher in patients utilizing the ICU post-operatively, even among uncomplicated patients with routine discharges. CONCLUSION: Most patients undergoing elective endovascular UIA repair in the United States are admitted to the ICU postoperatively. Only 12.7% have ICU needs, and these patients are predictable from pre-operative characteristics or peri-operative complications. Reducing ICU use in this subgroup of patients may be an important target to improve healthcare value in this patient population.

Repeat stereotactic radiosurgery for persistent cerebral arteriovenous malformations in pediatric patients.

OBJECTIVE: The purpose of this study was to describe the long-term outcomes and associated risks related to repeat stereotactic radiosurgery (SRS) for persistent arteriovenous malformations (AVMs) in pediatric patients. METHODS: Under the auspices of the International Radiosurgery Research Foundation, this retrospective multicenter study analyzed pediatric patients who underwent repeat, single-session SRS between 1987 and 2022. The primary outcome variable was a favorable outcome, defined as nidus obliteration without hemorrhage or neurological deterioration. Secondary outcomes included rates and probabilities of hemorrhage, radiation-induced changes (RICs), and cyst or tumor formation. RESULTS: The cohort included 83 pediatric patients. The median patient age was 11 years at initial SRS and 15 years at repeat SRS. Fifty-seven children (68.7%) were managed exclusively using SRS, and 42 (50.6%) experienced hemorrhage prior to SRS. Median AVM diameter and volume were substantially different between the first (25 mm and 4.5 cm3, respectively) and second (16.5 mm and 1.6 cm3, respectively) SRS, while prescription dose and isodose line remained similar. At the 5-year follow-up evaluation from the second SRS, nidus obliteration was achieved in 42 patients (50.6%), with favorable outcome in 37 (44.6%). The median time to nidus obliteration and hemorrhage was 35.5 and 38.5 months, respectively. The yearly cumulative probability of favorable outcome increased from 2.5% (95% CI 0.5%-7.8%) at 1 year to 44% (95% CI 32%-55%) at 5 years. The probability of achieving obliteration followed a similar pattern and reached 51% (95% CI 38%-62%) at 5 years. The 5-year risk of hemorrhage during the latency period after the second SRS reached 8% (95% CI 3.2%-16%). Radiographically, 25 children (30.1%) had RICs, but only 5 (6%) were symptomatic. Delayed cyst formation occurred in 7.2% of patients, with a median onset of 47 months. No radiation-induced neoplasia was observed. CONCLUSIONS: The study results showed nidus obliteration in most pediatric patients who underwent repeat SRS for persistent AVMs. The risks of symptomatic RICs and latency period hemorrhage were quite low. These findings suggest that repeat radiosurgery should be considered when treating pediatric patients with residual AVM after prior SRS. Further study is needed to define the role of repeat SRS more fully in this population.

Localization of spinal dural arteriovenous fistulas from the spatial relationships of perimedullary vessels on standard MRI.

OBJECTIVE: The goal in this study was to explore the spatial relationship of perimedullary vessels visualized on MRI to localize the side and the site of spinal dural arteriovenous fistula (SDAVF). METHODS: A retrospective analysis of 30 consecutive patients diagnosed with SDAVF on MRI was undertaken. Two experienced reviewers blinded to all reports and angiographic images analyzed T2-weighted as well as postcontrast T1-weighted sequences. A focal prominent zone of perimedullary vessels with lateralization to one side in the thecal space was evaluated to locate the side and the site of the fistula. Spinal digital subtraction angiography served as the gold standard technique. RESULTS: Good interrater agreement (κ = 0.77) was shown for the diagnosis of SDAVF with perimedullary vessels on T2-weighted MRI. Flow voids on T2-weighted MRI demonstrated a sensitivity of 1.0 (95% CI 1.0-1.0) and an accuracy of 0.87 (95% CI 0.79-0.95) to identify the presence of fistula. The flow voids on T2-weighted MRI also demonstrated 0.88 (95% CI 0.71-1.03) sensitivity and 0.81 (95% CI 0.70-0.92) accuracy to identify the side of SDAVF. Furthermore, flow voids on T2-weighted MRI showed 0.87 (95% CI 0.71-1.03) sensitivity and 0.87 (95% CI 0.79-0.95) accuracy to identify the site of SDAVF within 3 vertebral levels above or below the actual site. Area under the receiver operating characteristic curve demonstrated significant results (0.87 [95% CI 0.73-1.0]; p < 0.001) for flow voids on T2-weighted MRI to identify the site of shunts within 3 vertebral levels in the cranial or caudal direction. CONCLUSIONS: Spatial distribution of perimedullary vessels observed on standard MRI show promise to locate the side and the site of fistula in patients with SDAVF.

Third Stereotactic Radiosurgery for Residual Arteriovenous Malformations: A Retrospective Multicenter Study.

BACKGROUND AND OBJECTIVES: There are no studies evaluating the efficacy and safety of more than 2 stereotactic radiosurgery (SRS) procedures for cerebral arteriovenous malformations (AVM). The aim of this study was to provide evidence on the role of third single-session SRS for AVM residual. METHODS: This multicenter, retrospective study included patients managed with a third single-session SRS procedure for an AVM residual. The primary study outcome was defined as AVM nidus obliteration without AVM bleeding or symptomatic radiation-induced changes (RIC). Secondary outcomes evaluated were AVM obliteration, AVM hemorrhage, asymptomatic, and symptomatic RIC. RESULTS: Thirty-eight patients (20/38 [52.6%] females, median age at third SRS 34.5 [IQR 20] years) were included. The median clinical follow-up was 46 (IQR 14.8) months, and 17/38 (44.7%) patients achieved favorable outcome. The 3-year and 5-year cumulative probability rates of favorable outcome were 23% (95% CI = 10%-38%) and 53% (95% CI = 29%-73%), respectively. The cumulative probability of AVM obliteration at 3 and 5 years after the third SRS was 23% (95% CI = 10%-37%) and 54% (95% CI = 29%-74%), respectively. AVM bleeding occurred in 2 patients, and 1 of them underwent subsequent resection. The cumulative probability rate of post-SRS AVM hemorrhage remained constant at 5.3% (95% CI = 1%-16%) during the first 5 years of follow-up. Transient symptomatic RIC managed conservatively occurred in 5/38 patients (13.2%) at a median time of 12.5 (IQR 22.5) months from third SRS. Radiation-induced cyst formation was noted in 1 patient (4.2%) 19 months post-SRS. No mortality, radiation-associated malignancy, or permanent symptomatic RIC was noted during follow-up. CONCLUSION: A third single-session SRS to treat a residual intracranial AVM offers obliteration in most patients. The risk of RIC was low, and these effects were transient. While not often required, a third SRS can be performed in patients with persistent residual AVMs.

Effect of cerebral arteriovenous malformation location on outcomes of repeat, single-fraction stereotactic radiosurgery: a matched-cohort analysis.

OBJECTIVE: Patients with deep-seated arteriovenous malformations (AVMs) have a higher rate of unfavorable outcome and lower rate of nidus obliteration after primary stereotactic radiosurgery (SRS). The aim of this study was to evaluate and quantify the effect of AVM location on repeat SRS outcomes. METHODS: This retrospective, multicenter study involved 505 AVM patients managed with repeat, single-session SRS. The endpoints were nidus obliteration, hemorrhage in the latency period, radiation-induced changes (RICs), and favorable outcome. Patients were split on the basis of AVM location into the deep (brainstem, basal ganglia, thalamus, deep cerebellum, and corpus callosum) and superficial cohorts. The cohorts were matched 1:1 on the basis of the covariate balancing score for volume, eloquence of location, and prescription dose. RESULTS: After matching, 149 patients remained in each cohort. The 5-year cumulative probability rates for favorable outcome (probability difference -18%, 95% CI -30.9 to -5.8%, p = 0.004) and AVM obliteration (probability difference -18%, 95% CI -30.1% to -6.4%, p = 0.007) were significantly lower in the deep AVM cohort. No significant differences were observed in the 5-year cumulative probability rates for hemorrhage (probability difference 3%, 95% CI -2.4% to 8.5%, p = 0.28) or RICs (probability difference 1%, 95% CI -10.6% to 11.7%, p = 0.92). The median time to delayed cyst formation was longer with deep-seated AVMs (deep 62 months vs superficial 12 months, p = 0.047). CONCLUSIONS: AVMs located in deep regions had significantly lower favorable outcomes and obliteration rates compared with superficial lesions after repeat SRS. Although the rates of hemorrhage in the latency period and RICs in the two cohorts were comparable, delayed cyst formation occurred later in patients with deep-seated AVMs.

Safety and efficacy of endovascular versus microsurgical treatment of unruptured wide-necked middle cerebral artery aneurysms: a propensity score-matched analysis of the NeuroVascular Quality Initiative Quality Outcomes Database Cerebral Aneurysm Registry.

OBJECTIVE: Unruptured, wide-necked middle cerebral artery (WN-MCA) aneurysms have traditionally been considered ideal candidates for microsurgery (MS), although endovascular treatment (EVT) has dramatically increased in popularity with the advent of novel devices such as intrasaccular flow disruptors. The purpose of this study was to evaluate the safety and efficacy of MS versus EVT for unruptured WN-MCA aneurysms. METHODS: The NeuroVascular Quality Initiative Quality Outcomes Database (NVQI-QOD) Cerebral Aneurysm Registry, a multiinstitutional, prospectively collected procedural database, was queried for cases of unruptured WN-MCA aneurysms treated with MS or EVT between 2015 and 2022. A wide neck was defined as an aneurysm neck ≥ 4 mm or a dome/neck ratio ≤ 2. Demographics and aneurysm characteristics were queried. Propensity score matching (PSM) was utilized to match aneurysm size, number of aneurysms treated, patient age, and aneurysm status. Safety outcomes were evaluated including intraoperative and postoperative complication rates. Aneurysm occlusion status and clinical outcomes using the modified Rankin Scale (mRS) score at discharge and the last follow-up were also assessed. RESULTS: Of 671 unruptured MCA aneurysms, 319 were wide necked. Thirty cases were excluded, as the aneurysm had been previously treated. Two hundred eighty-nine operations (203 EVT, 86 MS) in 282 patients satisfied inclusion criteria. After PSM, there were 86 operations in each group for analysis. The mean aneurysm width was 5.0 (EVT) versus 4.9 mm (MS; p = 0.285). Safety data showed similar intraoperative (7.0% EVT vs 3.5% MS, p = 0.496) and postoperative (4.7% vs 7%, p = 0.746) complication rates. The MS patients were more likely to have complete aneurysm occlusion at discharge (90.4% vs 58.8%, p < 0.001). In a limited subset of patients (52.9%) for whom outcome data were available, the EVT patients were more likely to have an mRS score 0 at discharge (50/59 [84.7%] vs 29/54 [53.7%], p < 0.0003] and at the last follow-up (36/55 [65.5%] vs 13/36 [36.1%], p = 0.006). CONCLUSIONS: This study describes a large, modern cohort of propensity score-matched patients who underwent treatment of unruptured WN-MCA aneurysms. Safety data on intraoperative and postoperative complication rates were similar in both treatment groups. MS was more likely to result in complete aneurysm occlusion at discharge. In a subset of patients with available outcome data, EVT was associated with better functional outcomes at discharge and the last follow-up. Given the lack of complete follow-up data and rates of retreatment, these results should be interpreted cautiously.

Conscious sedation by sedation-trained interventionalists versus anesthesia providers in patients with acute ischemic stroke undergoing endovascular thrombectomy: A propensity score-matched analysis.

BACKGROUND: The appropriate choice of perioperative sedation during endovascular thrombectomy for ischemic stroke is unknown. Few studies have evaluated the role of nursing-administered conscious sedation supervised by a trained interventionalist. OBJECTIVE: To compare the safety and efficacy of endovascular thrombectomy for ischemic stroke performed with nursing-administered conscious sedation supervised by a trained interventionalist with monitored anesthesia care supervised by an anesthesiologist. METHODS: A retrospective review of a prospectively collected stroke registry was performed. The primary outcome was functional independence at 90 days, defined as a modified Rankin score of 0-2. Propensity score matching was performed to control for known confounders including patient comorbidities, access type, and direct-to-suite transfers. RESULTS: A total of 355 patients underwent endovascular thrombectomy for large vessel occlusion between 2018 and 2022. Thirty five patients were excluded as they arrived at the endovascular suite intubated. Three hundred and twenty patients were included in our study, 155 who underwent endovascular thrombectomy with nursing-administered conscious sedation and 165 who underwent endovascular thrombectomy with monitored anesthesia care. After propensity score matching, there were 111 patients in each group. There was no difference in modified Rankin score 0-2 at 90 days (26.1% vs 35.1%, p = 0.190). Patients undergoing monitored anesthesia care received significantly more vasoactive medications (23.4% vs 49.5%, p < 0.001) and had a lower intraoperative minimum systolic blood pressure (134 vs 123 mmHg, p < 0.046). There was no difference in procedural efficacy, safety, intubation rates, and postoperative complications. CONCLUSION: Perioperative sedation with nursing-administered conscious sedation may be safe and effective in patients undergoing endovascular thrombectomy for ischemic stroke.

Outcome Evaluation of Repeat Stereotactic Radiosurgery for Cerebral Arteriovenous Malformations.

BACKGROUND: Repeat stereotactic radiosurgery (SRS) for persistent cerebral arteriovenous malformation (AVM) has generally favorable patient outcomes. However, reporting studies are limited by small patient numbers and single-institution biases. The purpose of this study was to provide the combined experience of multiple centers, in an effort to fully define the role of repeat SRS for patients with arteriovenous malformation. METHODS: This multicenter, retrospective cohort study included patients treated with repeat, single-fraction SRS between 1987 and 2022. Follow-up began at repeat SRS. The primary outcome was a favorable patient outcome, defined as a composite of nidus obliteration in the absence of hemorrhage or radiation-induced neurological deterioration. Secondary outcomes were obliteration, hemorrhage risk, and symptomatic radiation-induced changes. Competing risk analysis was performed to compute yearly rates and identify predictors for each outcome. RESULTS: The cohort comprised 505 patients (254 [50.3%] males; median [interquartile range] age, 34 [15] years) from 14 centers. The median clinical and magnetic resonance imaging follow-up was 52 (interquartile range, 61) and 47 (interquartile range, 52) months, respectively. At last follow-up, favorable outcome was achieved by 268 (53.1%) patients (5-year probability, 50% [95% CI, 45%-55%]) and obliteration by 300 (59.4%) patients (5-year probability, 56% [95% CI, 51%-61%]). Twenty-eight patients (5.6%) experienced post-SRS hemorrhage with an annual incidence rate of 1.38 per 100 patient-years. Symptomatic radiation-induced changes were evident in 28 (5.6%) patients, with most occurring in the first 3 years. Larger nidus volumes (between 2 and 4 cm3, subdistribution hazard, 0.61 [95% CI, 0.44-0.86]; P=0.005; >4 cm3, subdistribution hazard, 0.47 [95% CI, 0.32-0.7]; P<0.001) and brainstem/basal ganglia involvement (subdistribution hazard, 0.6 [95% CI, 0.45-0.81]; P<0.001) were associated with reduced probability of favorable outcome. CONCLUSIONS: Repeat SRS confers reasonable obliteration rates with a low complication risk. With most complications occurring in the first 3 years, extending the latency period to 5 years generally increases the rate of favorable patient outcomes and reduces the necessity of a third intervention.

Variation in Carotid Artery Stenosis Measurements Among Facilities Seeking Carotid Stenting Facility Accreditation.

BACKGROUND: Based on the inclusion criteria of clinical trials, the degree of cervical carotid artery stenosis is often used as an indication for stent placement in the setting of extracranial carotid atherosclerotic disease. However, the rigor and consistency with which stenosis is measured outside of clinical trials are unclear. In an agreement study using a cross-sectional sample, we compared the percent stenosis as measured by real-world physician operators to that measured by independent expert reviewers. METHODS: As part of the carotid stenting facility accreditation review, images were obtained from 68 cases of patients who underwent carotid stent placement. Data collected included demographics, stroke severity measures, and the documented degree of stenosis, termed operator-reported stenosis (ORS), by 34 operators from 14 clinical sites. The ORS was compared with reviewer-measured stenosis (RMS) as assessed by 5 clinicians experienced in treating carotid artery disease. RESULTS: The median ORS was 90.0% (interquartile range, 80.0%-90.0%) versus a median RMS of 61.1% (interquartile range, 49.8%-73.6%), with a median difference of 21.8% (interquartile range, 13.7%-34.4%), P<0.001. The median difference in ORS and RMS for asymptomatic versus symptomatic patients was not statistically different (24.6% versus 19.6%; P=0.406). The median difference between ORS and RMS for facilities granted initial accreditation was smaller compared with facilities whose accreditation was delayed (17.9% versus 25.5%, P=0.035). The intraclass correlation between ORS and RMS was 0.16, indicating poor agreement. If RMS measurements were used, 72% of symptomatic patients and 10% of asymptomatic patients in the population examined would meet the Centers for Medicare and Medicaid Services criteria for stent placement. CONCLUSIONS: Real-world operators tend to overestimate carotid artery stenosis compared with external expert reviewers. Measurements from facilities granted initial accreditation were closer to expert measurements than those from facilities whose accreditation was delayed. Since decisions regarding carotid revascularization are often based on percent stenosis, such measuring discrepancies likely lead to increased procedural utilization.

Neuroendovascular Procedures in Patients with Ehlers-Danlos Type IV: Multicenter Case Series and Systematic Review.

BACKGROUND: Ehlers-Danlos type IV or vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited disorder characterized by profound vascular fragility resulting from defective production of type III procollagen. Cerebrovascular diseases including spontaneous dissections, cerebral aneurysms, and cavernous carotid fistulae are common. Endovascular therapies in this patient population are known to be higher risk, although many studies (before 2000) involved older techniques and equipment. The purpose of this study is to investigate the safety and efficacy of modern neuroendovascular techniques in the treatment of cerebrovascular diseases in patients with vEDS. METHODS: We combined a multi-institutional retrospective case series at 3 quaternary-care centers with a systematic literature review of individual case reports and case series spanning 2000-2021 to evaluate the safety and efficacy of neuroendovascular procedure in patients with vEDS with cerebrovascular diseases. RESULTS: Fifty-nine patients who underwent 66 neuroendovascular procedures were evaluated. Most of the patients had direct cavernous carotid fistulas (DCCF). Neuroendovascular procedures had a 94% success rate, with a complication rate of 30% and a mortality of 7.5%. CONCLUSIONS: Neuroendovascular procedures can be performed with a high rate of success in the treatment of cerebrovascular diseases in patients with vEDS, although special care is required because complication rates and mortality are high. Access site and procedure-related vascular injuries remain a significant hurdle in treating vEDS with cerebrovascular diseases, even with modern techniques.

Hemorrhage and Recurrence of Obliterated Brain Arteriovenous Malformations Treated With Stereotactic Radiosurgery.

BACKGROUND: Although complete nidal obliteration of brain arteriovenous malformations (AVM) is generally presumed to represent durable cure, postobliteration hemorrhage, and AVM recurrence have become increasingly recognized phenomena. The goal of the study was to define hemorrhage and nidal recurrence risks of obliterated AVMs treated with stereotactic radiosurgery (SRS). METHODS: This is a retrospective cohort study from the International Radiosurgery Research Foundation comprising AVM patients treated between 1987 and 2020. Patients with AVM obliteration on digital subtraction angiography (DSA) were included. Outcomes were (1) hemorrhage and (2) AVM recurrence. Follow-up duration began at the time of AVM obliteration and was censored at subsequent hemorrhage, AVM recurrence, additional AVM treatment, or loss to follow-up. Annualized risk and survival analyses were performed. A sensitivity analysis comprising patients with AVM obliteration on magnetic resonance imaging or DSA was also performed for postobliteration hemorrhage. RESULTS: The study cohort comprised 1632 SRS-treated patients with AVM obliteration on DSA. Pediatric patients comprised 15% of the cohort, and 42% of AVMs were previously ruptured. The mean imaging follow-up after AVM obliteration was 22 months. Among 1607 patients with DSA-confirmed AVM obliteration, 16 hemorrhages (1.0%) occurred over 2223 patient-years of follow-up (0.72%/y). Of the 1543 patients with DSA-confirmed AVM obliteration, 5 AVM recurrences (0.32%) occurred over 2071 patient-years of follow-up (0.24%/y). Of the 16 patients with postobliteration hemorrhage, AVM recurrence was identified in 2 (12.5%). In the sensitivity analysis comprising 1939 patients with post-SRS AVM obliteration on magnetic resonance imaging or DSA, 16 hemorrhages (0.83%) occurred over 2560 patient-years of follow-up (0.63%/y). CONCLUSIONS: Intracranial hemorrhage and recurrent arteriovenous shunting after complete nidal obliteration are rare in AVM patients treated with SRS, and each phenomenon harbors an annual risk of <1%. Although routine postobliteration DSA cannot be recommended to SRS-treated AVM patients, long-term neuroimaging may be advisable in these patients.

Role of Neurovascular Compression of Oculomotor Nerve in Ophthalmoplegic Migraine.

Ophthalmoplegic migraine is considered to occur more commonly in children than in adults. It commonly affects the oculomotor nerve among the cranial nerves. Demyelination of the nerve is proposed as the main mechanism for the etiology of ophthalmoplegic migraine, though it is not fully understood. Neurovascular compression as a cause of ophthalmoplegic migraine has not been well demonstrated in children. In this report, we present a case of a 13-year-old male with recurrent episodes of left ophthalmoplegic migraine. Oculomotor nerve enhancement with swelling was evident on MRI at the exit zone. Magnetic resonance angiography (MRA) revealed a sharp loop of the left posterior cerebral artery compressing the nerve. The case highlighted the unusual etiology of neurovascular compression resulting in ophthalmoplegic migraine in a pediatric patient. A supplemental case of ophthalmoplegic migraine in a seven-year-old male is also shown to highlight the role of neurovascular compression and the importance of using MR angiography to evaluate cases presenting clinically with ophthalmoplegic migraine.

Magnetic Resonance Angiography After Flow Diversion: The Use of Complementary Magnetic Resonance Angiography Techniques to Monitor Aneurysm Occlusion and Device and Arterial Branch Patency After Flow Diverter Placement.

BACKGROUND: Few studies have evaluated flow diversion with magnetic resonance angiography (MRA). Studies have shown better success of MRA in assessing the aneurysm response, but limited success in assessing stent patency. The patency of arterial branches on MRA remains to be explored. METHODS: Retrospective evaluation of 31 consecutive cases of carotid aneurysms treated with flow diversion was performed with noncontrast time-of-flight (TOF), contrast-enhanced TOF, and cine MRA (time-resolved angiography with interleaved stochastic trajectories) independently by 2 investigators for aneurysm occlusion, stent patency, and arterial branch patency. Digital subtraction angiography served as the gold standard technique. RESULTS: Patients were 6 men and 25 women with a mean ± SD age of 57.8 ± 12.27 years (range, 32-79 years). Stent patency, aneurysm occlusion, and branch patency mostly revealed substantial to perfect interobserver agreement (κ >0.60). Sensitivity, specificity, positive predictive value, and negative predictive value for stent patency on raw data images of TOF were 0.50, 0.86, 0.20, and 0.96 and on contrast-enhanced TOF were 1.0, 0.93, 0.50, and 1.0. Ranges for aneurysm response on the 3 MRA scans were 0.78-0.89 for sensitivity, 0.54-0.92 for specificity, 0.73-0.93 for positive predictive value, and 0.78-0.86 for negative predictive value. Ranges for arterial branch patency among the 3 MRA scans were 0.87-0.96 for sensitivity, 0.50-1.0 for specificity, 0.90-1.0 for positive predictive value, and 0.33-0.80 for negative predictive value. CONCLUSIONS: Aneurysm occlusion, stent patency, and arterial branch patency in flow diversion can be successfully evaluated with the combination of 3 MRA techniques.

Patterns of prophylactic anticonvulsant use in spontaneous intracerebral and subarachnoid hemorrhage: results of a practitioner survey.

BACKGROUND: The use of prophylactic anti-seizure medications (ASMs) in the management of patients with spontaneous intracerebral hemorrhage (sICH) and aneurysmal subarachnoid hemorrhage (aSAH) is controversial. OBJECTIVE: The purpose of this survey was to better characterize the current state of prophylactic ASM use in sICH and aSAH in North America. METHODS: US and Canadian neurosurgeons, neurologists, and interventional neuroradiologists with an interest in or expertise in the management of neurovascular disease were surveyed using an electronic survey tool. RESULTS: Seven hundred ninety-four survey requests were sent; responses were received from 103 (13%). The majority of respondents were neurosurgeons (84%). Thirty-eight percent of respondents self-identified as vascular neurosurgeons and 10% self-identified as neurocritical care specialists. Seventy-two percent were in academic practice. When asked their preference for ASM prophylaxis (aSAH, sICH, or both), the most common response was to use prophylaxis in both aSAH and sICH (43, 45%). Twenty-one (22%) did not use routine prophylaxis, while 22 (23%) used prophylaxis only in aSAH and 9 (9%) only in sICH. The majority of practitioners (35, 67%) who answered that they used ASM prophylaxis in sICH, used ASMs selectively. For aSAH, the vast majority (53, 82%) used prophylaxis for all patients. Respondents felt that they were more likely to use ASMs for sICH patients if the sICH was in a cortical location, supratentorial location, or was related to a structural abnormality (e.g., tumor, arteriovenous malformation) Levetiracetam (Keppra) was the most commonly used ASM (73, 99%). When asked whether the statement "Current AHA/ASA Guidelines recommend against the use of prophylactic anticonvulsants in spontaneous ICH" was true or false, 78 (83%) responded correctly that the recommendation is true. Only 24 respondents answered the question as to whether they would be willing to randomize sICH and/or aSAH patients to management with or without ASM prophylaxis. Of these, 13 (54%) said they would be willing to randomize sICH patients, while only 6 (25%) were willing to randomize aSAH patients. There were no statistically significant differences in responses to survey questions when analyzed by practice type (academic versus non-academic) or physician specialty (critical care versus non-critical care, or vascular neurology/neurosurgery versus other). CONCLUSION: The use of ASMs for seizure prophylaxis after sICH and aSAH remains widespread despite the lack of any specific evidence-based guideline to support the practice. A large-scale randomized controlled trial is needed to add clarity to the practice of prophylactic ASM use in patients with spontaneous intracranial hemorrhage.

Risk Factors Associated with ICU-Specific Care in Patients Undergoing Endovascular Treatment of Unruptured Intracranial Aneurysms.

BACKGROUND: Multiple studies suggest routine postoperative intensive care unit (ICUs) stays in presumed high-risk neurosurgical procedures may be unnecessary. Our objective was to evaluate the risk factors associated with ICU-specific needs in patients undergoing elective endovascular treatment of unruptured intracranial aneurysms. METHODS: A retrospective review of consecutive patients undergoing elective endovascular treatment of unruptured aneurysms was performed between January 2010 and January 2020 in a single academic medical center. Patient demographic information, aneurysm and treatment characteristics, intraoperative and postoperative complications, as well as ICU-specific needs, were abstracted. The primary outcome was ICU-specific needs. RESULTS: A total of 382 patient encounters in 344 unique patients were abstracted. 13.6% (52 of 382) of patient encounters had an ICU-specific need. Multivariate analysis revealed that age [adjusted odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01-1.07, p = 0.03], procedure duration greater 200 min (adjusted OR 2.75, 95% CI 1.34-5.88, p = 0.007), and any intraoperative complication (adjusted OR 20.41, CI 7.97-56.57, p < 0.001) were independent predictors of postoperative ICU-specific needs. The majority of ICU-specific needs (94%, 49 of 52) occurred within 6 h of surgery. CONCLUSIONS: Our results show that age, procedure duration greater than or equal to 200 min, and intraoperative complication were independent predictors of postoperative ICU-specific needs in patients presenting for elective endovascular treatment of unruptured intracranial aneurysms. The majority of ICU-specific needs and associated complications occurred in the immediate postoperative period. This data can be used to help decide the appropriate postoperative level of care in this patient population.

Balloon-Assisted Roadmap Technique to Enable Flow Diversion of a High-Flow Direct Carotid-Cavernous Fistula.

BACKGROUND: The use of flow diverters as a first-line treatment for direct carotid cavernous fistula (CCF) is a relatively new approach in the neurointerventional field which allows obliteration of the fistula with less mass effect from coils in the cavernous sinus. Safe and successful deployment of a flow diverter requires adequate imaging of the parent vessel, which may be challenging in the setting of high-flow CCF without antegrade flow. OBJECTIVE: To facilitate adequate parent vessel imaging in the setting of high-flow CCF to enable the safe development of a flow diverter device. METHODS: Here we present the case of a patient with delayed presentation of post-traumatic direct CCF after a motor vehicle accident, with no antegrade flow past the fistulous connection. We used temporary balloon occlusion of the fistulous connection to enable road-map imaging of the parent vessel and flow-diverter placement. "Drag and drop" device opening in the middle cerebral artery facilitated better deployment of the flow-diverter against retrograde cavernous flow through the fistula. RESULTS: Temporary balloon occlusion of the fistulous connection was used to acquire a roadmap to facilitate safe deployment of a flow diverter and subsequent treatment of the CCF with transvenous coil embolization, with complete resolution of symptoms. CONCLUSION: Balloon-assisted roadmap use is a novel means of visualizing the parent vessel in direct CCF to facilitate safe flow diverter deployment.

Management of neurophysiological monitoring changes during carotid endarterectomy exposure.

BACKGROUND: Carotid endarterectomy (CEA) is a safe and effective operation in the management of carotid stenosis. Intraoperative neurophysiologic monitoring (IONM) changes during carotid clamping has been well studied, but there is scant evidence detailing IONM changes during carotid exposure. OBJECTIVE: We analyzed our experience with IONM changes during CEA exposure to determine whether multimodal IONM changes during exposure predict outcomes and how best to manage this challenging clinical scenario. METHODS: We reviewed all CEAs performed at our medical center between January 2015 and June 2020 and identified patients with multimodal IONM changes during exposure of the carotid artery. Our primary outcomes were perioperative stroke and functional outcomes. Functional outcomes were measured by modified Rankin scale (mRS), with good functional outcome defined at mRS scores 0-3. We also reviewed our intraoperative IONM change management strategies. RESULTS: Five patients (4 males, 1 female) with an average age of 67 ± 12 years had intraoperative IONM changes during carotid exposure. Among these, three patients were discharged with good functional outcome, and four patients had a good functional outcome at last follow-up. Two patients had perioperative stroke, half of which resulted in significant disability. One patient was transferred to the neuroendovascular suite intraoperatively for evaluation for thromboembolism followed by angioplasty and stenting with distal protection. CONCLUSION: Intraoperative IONM changes during carotid exposure predict outcomes in CEA. We propose that transition to the neuroendovascular suite following significant IONM changes during carotid exposure may be a useful strategy for management of this challenging clinical scenario. This approach provides the opportunity to evaluate and treat thromboembolism and still complete carotid revascularization when appropriate. This algorithm may be particularly useful in the era of dual trained vascular neurosurgeons.

Self-expanding covered stent placement to treat a pseudoaneurysm caused by iatrogenic vertebral artery injury.

Vertebral artery injuries account for approximately 19% of cerebral vascular injuries and are typically managed conservatively. However, some patients require operative intervention to gain control of an active hemorrhage, either via surgical ligation or endovascular intervention. We present a case of iatrogenic vertebral artery injury occurring during cervical spine surgery which was treated emergently with a self-expanding covered stent. A 58-year-old male presented for cervical traction, C5 and C6 corpectomy, and possible C4 to T2 posterior fusion following a motor vehicle accident. Intraoperatively, following drilling the C5 endplate, copious bleeding was observed from injury to the right vertebral artery resulting in pseudoaneurysm formation. The patient was loaded with ticagrelor and a self-expanding covered stent was placed via a transfemoral approach, resulting in obliteration of the pseudoaneurysm prior to completion of his cervical spine surgery. Emergent self-expanding covered stent placement for iatrogenic vertebral artery injury in the setting of an intraoperative injury is a safe and effective option. Ticagrelor is a viable alternative to traditional dual antiplatelet therapy for preventing thromboembolic complications in this urgent setting.

Management of Internal Carotid Artery and Intracranial Anterior Circulation Tandem Occlusion with Stenting versus No Stenting: A Multicenter Study.

BACKGROUND: Tandem occlusion (TO) describes not only occlusion of the middle cerebral artery but a contemporaneous occlusion of the cervical internal carotid artery. There is a paucity of data over whether mechanical thrombectomy (MT) alone, MT with angioplasty, or MT with carotid artery stent placement is superior. We aim to address a gap in the literature comparing carotid stenting with mechanical thrombectomy (CSMT) and carotid angioplasty with mechanical thrombectomy (CAMT) in patients presenting with acute anterior circulation TOs. METHODS: This is a multicenter, retrospective study from 2012 to 2020 comparing CSMT and CAMT presenting with acute anterior circulation TOs. Primary outcomes of interest were functional status, perioperative stroke, mortality, and symptomatic intracranial hemorrhage (sICH). A total of 92 patients (66 vs. 26 in CSMT and CAMT, respectively) met inclusion criteria for analysis. RESULTS: There was no statistically significant difference in functional outcomes at 90-day follow-up (adjusted odds ratio [aOR] 0.82; 95% confidence interval [CI] 0.20-3.5; P = 0.46). In addition, there was no statistically significant difference in 90-day mortality (aOR 0.361; 95% CI 0.016-2.92; P = 0.532) and perioperative stroke rate (aOR 1.76; 95% CI 0.160-15.6; P = 0.613). However, sICH risk was significantly greater in the stent-treated cohort (aOR 3.94; 95% CI 0.529-37.4; P = 0.003). CONCLUSIONS: Functional outcomes, mortality, and perioperative stroke rates do not significantly differ in CSMT and CAMT procedures in the acute setting. However, CSMT-treated patients do appear to have an increased risk of sICH, potentially due to the use of additional antiplatelet agents following stent placement.