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Cerebrovascular disease encompasses a vast array of conditions. The imaging recommendations for stroke-related conditions involving noninflammatory steno-occlusive arterial and venous cerebrovascular disease including carotid stenosis, carotid dissection, intracranial large vessel occlusion, and cerebral venous sinus thrombosis are encompassed by this document. Additional imaging recommendations regarding complications of these conditions including intraparenchymal hemorrhage and completed ischemic strokes are also discussed. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation., (Copyright © 2024 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Background: Disorders of consciousness impair early recovery after aneurysmal subarachnoid hemorrhage (aSAH). Modafinil, a wakefulness-promoting agent, is efficacious for treating fatigue in stroke survivors, but data pertaining to its use in the acute setting are scarce. This study sought to assess the effects of modafinil use on mental status after aSAH., Methods: Modafinil timing and dosage, neurological examination, intubation status, and physical and occupational therapy participation were documented. Repeated-measures paired tests were used for a before-after analysis of modafinil recipients. Propensity score matching (1:1 nearest neighbor) for modafinil and no-modafinil cohorts was used to compare outcomes., Results: Modafinil (100-200 mg/day) was administered to 21% (88/422) of aSAH patients for a median (IQR) duration of 10.5 (4-16) days and initiated 14 (7-17) days after aSAH. Improvement in mentation (alertness, orientation, or Glasgow Coma Scale score) was documented in 87.5% (77/88) of modafinil recipients within 72 hours and 86.4% (76/88) at discharge. Of 37 intubated patients, 10 (27%) were extubated within 72 hours after modafinil initiation. Physical and occupational therapy teams noted increased alertness or participation in 47 of 56 modafinil patients (83.9%). After propensity score matching for baseline covariates, the modafinil cohort had a greater mean (SD) change in Glasgow Coma Scale score than the no-modafinil cohort at discharge (2.2 [4.0] vs. -0.2 [6.32], P = 0.003)., Conclusions: A temporal relationship with improvement in mental status was noted for most patients administered modafinil after aSAH. These findings, a favorable adverse-effect profile, and implications for goals-of-care decisions favor a low threshold for modafinil initiation in aSAH patients in the acute-care setting., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: Aneurysmal subarachnoid hemorrhage (aSAH) is associated with increased blood-brain barrier permeability, disrupted tight junctions, and increased cerebral edema. Sulfonylureas are associated with reduced tight-junction disturbance and edema and improved functional outcome in aSAH animal models, but human data are scant. We analyzed neurological outcomes in aSAH patients prescribed sulfonylureas for diabetes mellitus., Methods: Patients treated for aSAH at a single institution (August 1, 2007-July 31, 2019) were retrospectively reviewed. Patients with diabetes were grouped by presence or absence of sulfonylurea therapy at hospital admission. The primary outcome was favorable neurologic status at last follow-up (modified Rankin Scale score ≤2). Variables with an unadjusted P-value of <0.20 were included in a propensity-adjusted multivariable logistic regression analysis to identify predictors of favorable outcomes., Results: Of 1013 aSAH patients analyzed, 129 (13%) had diabetes at admission, and 16 of these (12%) were receiving sulfonylureas. Fewer diabetic than nondiabetic patients had favorable outcomes (40% [52/129] vs. 51% [453/884], P = 0.03). Among diabetic patients, sulfonylurea use (OR 3.90, 95% CI 1.05-15.9, P = 0.046), Charlson Comorbidity Index <4 (OR 3.66, 95% CI 1.24-12.1, P = 0.02), and absence of delayed cerebral infarction (OR 4.09, 95% CI 1.20-15.5, P = 0.03) were associated with favorable outcomes in the multivariable analysis., Conclusions: Diabetes was strongly associated with unfavorable neurologic outcomes. An unfavorable outcome in this cohort was mitigated by sulfonylureas, supporting some preclinical evidence of a possible neuroprotective role for these medications in aSAH. These results warrant further study on dose, timing, and duration of administration in humans., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Sparse data exist on socioeconomic disparities among patients treated for aneurysmal subarachnoid hemorrhage (aSAH). The authors analyzed factors possibly influencing patient outcomes, including having a primary care physician (PCP) at admission, family/caregiver support, a foreign language barrier, primary payer status, and race., Methods: Socioeconomic data were abstracted for patients treated endovascularly or microsurgically for aSAH at a single center (January 1, 2014-July 31, 2019). Binary logistic regression analyses were used to identify independent predictors of an unfavorable outcome (modified Rankin Scale [mRS] score >2) and for predictive modeling., Results: Among 422 patients, the median (interquartile range) follow-up was 2 (1-23) months. Lack of caregiver support was the only socioeconomic factor associated with an unfavorable outcome at discharge. Independent predictors of mRS score >2 at last follow-up included baseline markers of disease severity (P ≤ 0.03), nonwhite race (OR, 1.69; P = 0.047), lack of caregiver support (OR, 5.55; P = 0.007), and lack of a PCP (OR, 1.96; P = 0.007). Adjusting for follow-up mediated the effects of race and PCP, although caregiver support remained significant and PCP was associated with a lower mortality risk independent of follow-up (OR, 0.51; P = 0.047). Predischarge socioeconomic factors, alongside disease severity, predicted a follow-up mRS score >2 with excellent discrimination (area under the receiver operating curve, 0.81; 95% CI, 0.77-0.86)., Conclusions: At a large, urban, comprehensive stroke center, patients with PCPs, caregiver support, and white race had significantly better long-term outcomes after aSAH. These results reflect disparities in access to healthcare after aSAH for vulnerable populations with extensive lifetime needs., (Copyright © 2023 Elsevier Inc. All rights reserved.)

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., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: The "weekend effect" is the negative effect on disease course and treatment resulting from being admitted to the hospital during a weekend. Whether the weekend effect is associated with worse outcomes for patients treated for aneurysmal subarachnoid hemorrhage (aSAH) is unknown. We assessed neurologic outcomes of patients with aSAH admitted during the weekend versus during the week., Methods: A retrospective database was reviewed to identify all patients with aSAH who received open or endovascular treatment from August 1, 2007, to July 31, 2019, at a quaternary center. The primary outcome was a poor neurologic outcome (modified Rankin Scale score >2). Propensity adjustment included age, sex, treatment type, Hunt and Hess grade, and Charlson Comorbidity Index., Results: A total of 1014 patients (women, 703 [69.3%]; men, 311 [30.7%]; mean age, 56 [standard deviation, 14]) met inclusion criteria; 726 (71.6%) had weekday admissions, and 288 (28.4%) had weekend admissions. There was no significant difference between patients with a weekday versus a weekend admission in mean (standard deviation) time to treatment (0.85 [1.29] vs. 0.93 [1.30] days, P = 0.10) or length of stay (19 [9] vs. 19 [9] days, P = 0.04). Total cost and rates of delayed cerebral ischemia and vasospasm were similar between the admission groups, both overall and within the open and endovascular treatment cohorts. After propensity adjustment, weekend admission was not a significant predictor of a modified Rankin Scale score greater than 2 (odds ratio [95% confidence interval]; 1.12 [0.85-1.49]; P = 0.4)., Conclusion: No difference in neurologic outcomes was associated with weekend admission among this cohort of patients with aSAH., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: The additional hospital costs associated with delayed cerebral ischemia (DCI) have not been well investigated in prior literature. In this study, the total hospital cost of DCI in aneurysmal subarachnoid hemmorhage (aSAH) patients treated at a single quaternary center was analyzed., Methods: All patients in the Post-Barrow Ruptured Aneurysm Trial treated for an aSAH between January 1, 2014, and July 31, 2019, were retrospectively analyzed. DCI was defined as cerebral infarction identified on computed tomography, magnetic resonance imaging, or autopsy after exclusion of procedure-related infarctions. The primary outcome was the difference in total cost (including hospital, discharge facility, and all follow-up) using a propensity-adjusted analysis. Propensity score covariate-adjusted linear regression analysis included age, sex, open versus endovascular treatment, Hunt and Hess score, and Charlson Comorbidity Index score., Results: Of the 391 patients included, 144 (37%) had DCI. Patients with DCI had a significantly greater cost compared to patients without DCI (mean standard deviation $112,081 [$54,022] vs. $86,159 [$38,817]; P < 0.001) and a significantly greater length of stay (21 days [11] vs. 18 days [8], P = 0.003, respectively). In propensity-adjusted linear regression analysis, both DCI (odds ratio, $13,871; 95% confidence interval, $7558-$20,185; P < 0.001) and length of stay (odds ratio, $3815 per day; 95% confidence interval, $3480-$4149 per day; P < 0.001) were found to significantly increase the cost., Conclusions: The significantly higher costs associated with DCI further support the evidence that adverse effects associated with DCI in aSAH pose a significant burden to the health care system., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Liver cirrhosis is associated with an increased risk of aneurysmal subarachnoid hemorrhage (aSAH). However, large studies analyzing the prognosis of cirrhotic patients after aSAH treatment are lacking. This study explores factors associated with inpatient mortality among aSAH patients with cirrhosis., Methods: All patients who underwent open or endovascular treatment for an aSAH at a large quaternary center between January 1, 2003, and July 31, 2019, were retrospectively reviewed. Patients were grouped into cirrhosis versus noncirrhosis groups. Univariate analysis determined variables associated with inpatient mortality. Variables with P < 0.20 were included in a propensity-adjusted multivariable logistic regression analysis to predict inpatient mortality., Results: A total of 1419 patients were treated for aSAH; 17 (1.2%) had confirmed cirrhosis. Inpatient mortality was significantly higher among cirrhotic patients than noncirrhotic patients (35.3% vs. 6.8%; P < 0.001). In the univariate analysis for inpatient mortality, the variables cirrhosis, age >65 years, Charlson Comorbidity Index >4, aneurysm size ≥10 mm, Hunt and Hess grade >3, Fisher grade 4, delayed cerebral ischemia (DCI), and posterior circulation aneurysm had P < 0.20 and were included in the multivariable analysis. The propensity-adjusted stepwise multivariable logistic regression analysis showed that cirrhosis (odds ratio [OR]: 12.7, 95% confidence interval [CI]: 3.3-48.7), Hunt and Hess grade >3 (OR: 3.9, 95% CI: 2.3-6.4), Fisher grade 4 (OR: 3.7, 95% CI: 1.3-10.7), and DCI (OR: 2.4, 95% CI: 1.5-3.9) were associated with inpatient mortality (P ≤ 0.01)., Conclusions: Cirrhosis was a predictor of inpatient mortality among aSAH patients and was a stronger predictor than DCI or a poor Hunt and Hess grade among patients in this study., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Nationwide study results have suggested varying trends in the incidence of aneurysmal subarachnoid hemorrhage (aSAH) over time. Herein, trends over time for aSAH treated at a quaternary care center are compared with low-volume hospitals., Methods: Cases were retrospectively reviewed for patients with aSAH treated at our institution. Trend analyses were performed on the number of aSAH hospitalizations, treatment type, Charlson Comorbidity Index (CCI), Hunt and Hess grade, aneurysm location, aneurysm type, and in-hospital mortality. The National Inpatient Sample (NIS) was queried to compare the CCI scores of our patients with those of patients in low-volume hospitals (<20 aSAH/year) in our census division., Results: Some 1248 patients (321 during 2004-2006; 927 during 2008-2018) hospitalized with aSAH were treated with endovascular therapy (489, 39%) or microsurgery (759, 61%). A significant downtrend in the annual aSAH caseload occurred (123 patients in 2004, 75 in 2018, P < 0.001). A linear uptrend was observed for the mean CCI score of patients (R  2  = 0.539, P < 0.001), with no change to in-hospital mortality (R  2  = 0.220, P = 0.24). Mean (standard deviation) CCI for small-volume hospitals treating aSAH within our division was significantly lower than that of our patient population (1.8 [1.6] vs 2.1 [2.0]) for 2012-2015., Conclusions: A decreasing number of patients were hospitalized with aSAH throughout the study. Compared with patients with aSAH admitted in 2004, those admitted more recently were sicker in terms of preexisting comorbidity and neurologic complexity. These trends could be attributable to the increasing availability of neurointerventional services at smaller-volume hospitals capable of treating healthier patients., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Although several commercially available sutureless anastomotic techniques are available, they are not routinely used in neurosurgery. We performed an in vivo flow analysis of end-to-end anastomosis using a microvascular coupler device in rats. We report our first clinical use of the microvascular anastomotic coupler., Methods: Bilateral rat common carotid arteries (CCAs) were exposed, and a microvascular coupler was used to perform 8 anastomoses. A microflow probe provided quantitative measurement of blood-flow volume. Flow augmentation was assessed with end-to-side anastomoses connecting the distal CCA to the jugular vein (JV). A patient with chronic dominant hemisphere atherosclerotic ischemic disease and progressive symptoms refractory to medical management underwent end-to-end cerebral artery bypass using the microvascular coupler., Results: Mean preanastomosis flow in the rat CCA was 3.95 ± 0.45 mL/min; this flow was maintained at 3.99 ± 0.24 mL/min on final measurements 54-96 minutes postanastomosis. Total occlusion time for each rat CCA was 12-19 minutes. After end-to-side anastomosis, with proximal and distal JV patent, CCA flow increased 477% to 22.8 ± 3.70 mL/min (P = 0.04, proximal; P = 0.01, distal). After in vivo testing, we successfully used the coupler clinically in a superficial temporal artery-to-middle cerebral artery bypass for dominant hemisphere flow augmentation., Conclusions: In vivo quantitative flow analysis demonstrated no flow difference between an unaltered artery and artery with end-to-end anastomosis using a microvascular coupler in rats. A 1-mm coupled anastomosis achieved a 4-fold flow increase with low-resistance venous outflow in rats, simulating increased arterial demand. The coupler was successfully used for extracranial-to-intracranial bypass in a patient., (Copyright © 2022 Elsevier Inc. All rights reserved.)

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., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Cerebrovascular disease is a broad topic. This document focuses on the imaging recommendations for the varied clinical scenarios involving intracranial aneurysms, vascular malformations, and vasculitis, which all carry high risk of morbidity and mortality. Additional imaging recommendations regarding complications of these conditions, including subarachnoid hemorrhage and vasospasm, are also covered. While each variant presentation has unique imaging recommendations, the major focus of this document is neurovascular imaging techniques. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment., (Copyright © 2021 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Background: Preoperative embolization of meningiomas to reduce tumor vascularity and intraoperative blood loss remains controversial. Incomplete devascularization on angiography is not significantly correlated with intraoperative estimated blood loss (EBL). Magnetic resonance imaging (MRI) may provide a better assessment of devascularization and prediction of EBL., Methods: We retrospectively analyzed patients undergoing preoperative embolization for intracranial meningiomas. Cohorts based on postembolization devascularization (>50% vs. ≤50%) were compared., Results: Of 84 patients with meningioma undergoing preoperative embolization, 35 (42%) had a postembolization MRI before resection and met study inclusion criteria. The mean tumor diameter was 4.9 ± 1.3 cm, and mean intraoperative EBL was 576 ± 341 mL. Compared with MRI, angiography overestimated devascularization in 22 patients (63%). Using pre- versus postembolization MRIs, 17 (49%) patients had a >50% decrease in enhancement, which was associated with lower mean intraoperative blood loss (444 ± 255 mL) compared with 17 patients with ≤50% devascularization (700 ± 374 mL) (P = 0.03). On angiography, the 22 (63%) patients who demonstrated >50% devascularization during embolization did not statistically differ in intraoperative EBL when compared with 13 (37%) patients with <50% angiographic devascularization. Patients with a ≤50% decrease in contrast enhancement on postembolization MRI were 9 times more likely to lose >500 mL blood intraoperatively during resection (95% confidence interval 1.6-54, P = 0.01)., Conclusions: Postembolization contrast-enhanced MRI is a better predictor of intraoperative blood loss during meningioma resection than postembolization angiography, which overestimates the degree of embolic devascularization. Postembolization preoperative MRI is warranted for optimal patient management., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Optimal management of patients with extracranial blunt cerebrovascular injury (BCVI) remains controversial, with both anticoagulation and antiplatelet therapy being recommended. The purpose of this study was to evaluate the efficacy and safety of using acetylsalicylic acid (ASA) in the management of BCVI., Methods: Patients with BCVI were identified from the registry of a Level 1 trauma center between 2010 and 2017. Digital imaging and electronic medical records were reviewed for patient information including demographic characteristics, injury type, therapy, outcomes, and follow-up., Results: Over the study period, 13,578 patients were admitted following blunt trauma, with 94 (0.7%) having confirmed BCVI (mean age, 42 years; 72% male). Mean Injury Severity Score and Glasgow Coma Score were 27 and 10, respectively. BCVI was identified in 130 vessels with Biffl grade I (38%) and grade II injury (29%) being most common. Twelve (13%) patients experienced an ischemic event, but only 3 events occurred after diagnosis. ASA was primary treatment for 56 (60%) patients. Thirty patients (32%) received no treatment; 21 patients died within 24 hours of primary injury. Only 4 patients had ASA contraindications. Four patients (7%) had ASA-related complications; there were 2 cases of intracranial hemorrhage progression and 2 cases of gastrointestinal bleeding. Follow-up vascular imaging at a mean of 36 days demonstrated stable or improved levels of BCVI in 94% of patients., Conclusions: An ASA-based management strategy for BCVI was efficacious and relatively safe in this study. This approach may be the preferred treatment for BCVI, but confirmation is needed., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Acute changes in mental status represent a broad collection of symptoms used to describe disorders in mentation and level of arousal, including the more narrowly defined diagnoses of delirium and psychosis. A wide range of precipitating factors may be responsible for symptom onset including infection, intoxication, and metabolic disorders. Neurologic causes that may be detected on neuroimaging include stroke, traumatic brain injury, nonconvulsive seizure, central nervous system infection, tumors, hydrocephalus, and inflammatory disorders. Not infrequently, two or more precipitating factors may be found. Neuroimaging with CT or MRI is usually appropriate if the clinical suspicion for an acute neurological cause is high, where the cause of symptoms is not found on initial assessment, and for patients whose symptoms do not respond appropriately to management. There was disagreement regarding the appropriateness of neuroimaging in cases where a suspected, nonneurologic cause is found on initial assessment. Neuroimaging with CT is usually appropriate for patients presenting with delirium, although the yield may be low in the absence of trauma or a focal neurological deficit. Neuroimaging with CT or MRI may be appropriate in the evaluation of new onset psychosis, although the yield may be low in the absence of a neurologic deficit. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment., (Copyright © 2019 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Objective: Preoperative embolization may facilitate skull base meningioma resection, but its safety and efficacy in the Onyx era have not been investigated. In this retrospective cohort study, we evaluated the outcomes of preoperative embolization of skull base meningiomas using Onyx as the primary embolysate., Methods: We queried an endovascular database for patients with skull base meningiomas who underwent preoperative embolization at our institution in 2007-2017. Patient, tumor, procedure, and outcome data were analyzed., Results: Twenty-eight patients (28 meningiomas) underwent successful preoperative meningioma embolization. The mean patient age ± SD was 56 ± 13 years, and 18 patients (64%) were women. The mean tumor size was 49 cm 3 . There were 1, 2, or 3 arterial pedicles embolized in 21 cases (75%), 6 cases (21%), and 1 case (4%), respectively. The embolized pedicles included branches of the middle meningeal artery in 19 cases (68%), the internal maxillary artery in 8 cases (29%), the ascending pharyngeal artery in 2 cases (7%), and the posterior auricular, ophthalmic, occipital, and anterior cerebral arteries in 1 case each (4%). The embolysates used were Onyx alone in 20 cases (71%), n-butyl cyanoacrylate alone in 3 cases (11%), coils/particles and Onyx/n-butyl cyanoacrylate in 2 cases each (7%), and Onyx and coils in 1 case (4%). The median degree of tumor devascularization was 60%. Significant neurologic morbidity occurred in 1 patient (4%) who developed symptomatic peritumoral edema after Onyx embolization., Conclusions: For appropriately selected skull base meningiomas supplied by dura mater-based arterial pedicles without distal cranial nerve supply, preoperative embolization with current embolysate technology affords substantial tumor devascularization with a low complication rate., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Rotational vertebral artery occlusion is a rare syndrome characterized by vertebrobasilar insufficiency secondary to position-dependent occlusion of the vertebral artery. Most cases reported in the literature have been attributed to osteophytic compression, either from the occipital condyle or within the transverse foramen. However, vertebral artery dissection secondary to motion in the setting of anomalous anatomy has not been reported., Case Description: To the authors' knowledge, rotational vertebral artery occlusion and dissection secondary to anomalous entrance into the transverse foramen have never been reported. The authors describe the case of a 42-year-old male who presented with multiple posterior circulation transient ischemic attacks. Standard digital subtraction cerebral angiography demonstrated a non-flow-limiting right vertebral artery dissection, while dynamic digital subtraction cerebral angiography was remarkable for right vertebral artery stenosis that worsened with neck rotation. Computed tomography angiography of the neck revealed an anomalous course of the right vertebral artery, which entered the transverse foramen at C4 with preforaminal compression by the anterior tubercle of the C5 transverse process. The patient had no further symptomatic events after decompression of the vertebral artery by resecting the anterior C5 tubercle., Conclusions: In the setting of codominant vertebral circulation and unilateral bony compression, the authors propose that neck rotation led to vertebral artery trauma, causing dissection complicated by thromboembolism. This is a novel and unusual entity that is different from Bowhunter's syndrome., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Dural arteriovenous fistulas (dAVFs) often are treated via transarterial or transvenous embolization. Incomplete penetration of the draining vein/occult residual often will become apparent on follow-up angiography, requiring repeat embolization, or at times, surgical resection., Case Description: A 41-year-old woman presented with cerebellar hemorrhage from a tentorial dAVF treated with transvenous coil embolization. Follow-up angiography disclosed a residual/recurrent fistula treated with transvenous Onyx embolization. After further follow-up angiography demonstrated another occult residual/recurrence, the fistula was disconnected with the tentorial dura excised via a retrosigmoid approach. Six-month follow-up angiography demonstrated no recurrence., Conclusions: Although endovascular treatment of dAVFs is generally first-line therapy, surgical disconnection of fistulas, particularly high-risk residual/recurrent fistulas, is an excellent option in well-selected cases., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Traumatic carotid cavernous fistula may occur as a complication of endovascular treatment of acute stroke. We report 3 cases of such lesions. All patients were initially managed conservatively. Two patients have remained asymptomatic. One patient became symptomatic with right eye proptosis, chemosis, and right lateral gaze diplopia 3 weeks post thrombectomy. He underwent endovascular embolization via transfemoral transvenous approach via the inferior ophthalmic vein., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Tandem occlusion resulting in acute ischemic stroke is associated with high morbidity and mortality and a poor response to thrombolytic therapy. The use of endovascular strategies for tandem stroke cases results in an improved outcome for this subgroup of patients. We present 2 cases with a pattern of tandem occlusion consisting of proximal obstruction at the origin of the common carotid artery (CCA) with concomitant intracranial occlusion treated by endovascular techniques., Methods: The 2 patients presented each with occlusion at the left CCA origin and ipsilateral intracranial vessel (left middle cerebral artery and carotid terminus, respectively). A transfemoral anterograde approach was used to deliver a balloon-mounted stent across the proximal CCA origin occlusion to gain access to the distal cerebral vasculature. Subsequently, a stent retriever assisted mechanical aspiration thrombectomy was used to revascularize the intracranial occlusion., Results: Complete revascularization with Thrombolysis in Cerebral Infarction scores of 2b and improvement in neurologic deficits occurred in both cases. Good clinical outcome was achieved for both patients at 3-month follow-up., Conclusions: An anterograde transfemoral approach should be considered in cases of tandem occlusion of the proximal CCA and middle cerebral artery., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Spinal arteriovenous malformations (sAVM) are rare vascular pathologies whose natural history remains incompletely understood. Advances in diagnostic imaging, coupled with the evolution of endovascular and microsurgical techniques have led to the description of a number of classification schemes for these lesions. An updated method has changed AVM classification from five categories of lesion based on source and location of feeder vessels to three categories based on pathophysiology. These categories include extradural arteriovenous fistulae (AVFs), intradural AVFs, extradural-intradural AVFs, intramedullary AVMs, and conus medullaris AVM each with individual subclassifications. Treatment outcomes have been shown to differ based on classification criteria. The increased use of advanced imaging prior to surgical intervention has facilitated the treatment of AVFs. Definitive diagnosis and characterization have traditionally required digital subtraction angiography, which is now being supplemented with other forms of noninvasive imaging such as computed tomography angiography (CTA) and magnetic resonance angiography (MRA). Epidemiologically, intradural dorsal AVFs account for 80% of all sAVMs, and are characterized by low-pressure shunts located in the sleeve of the dorsal nerve root. Microsurgical treatment has been shown to be highly effective in cases of intradural dorsal AVFs, although many cases are also amenable to durable occlusion using liquid embolics. Conus medullaris AVMs, which has only been recently characterized as a separate category of sAVM, is best treated using a combination of embolization and microsurgery. Successful treatment of sAVM mandates a thorough understanding of the anatomy and classification of these lesions. The purpose of this chapter is to review and summarize the classification, natural history, and prognosis of sAVMs., (© 2017 Elsevier B.V. All rights reserved.)

Objective: Direct factor Xa inhibitors rivaroxaban and apixaban are efficacious alternatives to warfarin and confer a lower risk of spontaneous intracranial hemorrhage (ICH); however, they lack a validated reversal strategy. We evaluated the efficacy and safety of 4-factor prothrombin complex concentrate (PCC) administration on rivaroxaban- and apixaban-mediated coagulopathy in patients with traumatic and spontaneous ICH., Methods: Retrospective review of patients presenting with traumatic and spontaneous ICH and concurrent use of rivaroxaban or apixaban. Demographic factors, reason for anticoagulation, hemorrhage type and location, Glasgow coma scale score, and when appropriate, ICH score, were included. Patient charts were reviewed for in-hospital mortality, thromboembolic events, pulmonary complications, worsening of hemorrhage, hemorrhagic complications after neurosurgical intervention, and 90-day modified Rankin scale score., Results: Eighteen patients met inclusion criteria; 16 used rivaroxaban and 2 used apixaban. Eight patients presented with traumatic ICH, 8 with hemorrhagic stroke, 1 with subarachnoid hemorrhage, and 1 patient with tumoral hemorrhage. Mean Glasgow coma scale score was 12.6 (range, 6-15) and mean ICH score was 2.3 (range, 0-4). After reversal with PCC, 1 patient (5.6%) demonstrated worsening of ICH on follow-up head computed tomography. PCCs were administered before emergent placement of an external ventricular drain in 1 individual, with no hemorrhagic complications. Six patients (33.3%) experienced in-hospital mortality: family withdrew care in 4 and 2 died due to pneumonia. There was 1 (5.6%) thromboembolic complication. Favorable outcomes at 90 days were seen in 6 patients (33.3%)., Conclusions: Despite no studies demonstrating the efficacy of 4-factor PCC administration for reversal of coagulopathy in patients on direct factor Xa inhibitors, our early experience demonstrates it to be safe, yet potentially reducing hemorrhagic complications and hematoma expansion in this critically ill population., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Diagnosing normal pressure hydrocephalus (NPH) remains challenging. Most clinical tests currently used to evaluate suspected NPH patients for shunt surgery are invasive, require inpatient admission, and are not without complications. An objective, noninvasive, and low-cost alternative would be ideal., Methods: A retrospective review was performed of prospectively collected dynamic gait index (DGI) scores, obtained at baseline and on every day of a 3- to 5-day lumbar cerebrospinal fluid (CSF) drainage trial on patients with suspected NPH at our institution., Results: Between 2003 and 2014, 170 patients were suspected to have primary NPH (166, 97.6%) or secondary NPH (4, 2.4%). Using responsiveness to lumbar CSF drainage and subsequent shunting as the reference standard, we found that a baseline DGI ≥ 7 was found to have significant ability in selecting patients for permanent CSF diverting shunt surgery: sensitivity of 84.2% (95% confidence interval [95% CI]: 75.6%-90.2%), specificity of 80.6% (95% CI 70.0%-88.0%), and diagnostic odds ratio of 22.1 (95% CI 9.9-49.3)., Conclusions: A baseline DGI ≥ 7 appears to provide an objective, low-cost, noninvasive measure to select patients with suspected NPH for a positive response to CSF diversion with high sensitivity, specificity and diagnostic odds ratio., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Bow hunter's syndrome is a rare vascular phenomenon characterized by insufficiency of the posterior cerebral circulation induced by rotation of the head within normal physiologic range. The neurosurgical literature on evidence-based diagnosis and management of the disease is scarce, and reports are largely limited to case studies., Methods: A retrospective chart review was performed on all patients referred to Barrow Neurological Institute during the period 1999-2013 with signs and symptoms that were possibly indicative of bow hunter's syndrome. Demographic data from patient charts were collected, and the patients' imaging studies were reviewed., Results: There were 14 patients referred to Barrow Neurological Institute with symptoms concerning for bow hunter's syndrome, and 11 of these patients were confirmed to have dynamic vertebral artery compression on angiography. The location of compression was centered on C1-2 (50%) or C5-7 (50%). The compressed vertebral artery was typically the left artery (72.7%), and in 54.5% of cases, rotation of the head to the contralateral side produced symptomatic dynamic compression. Surgical decompression, via either an anterior (44.4%) or a posterior (55.6%) approach, was eventually performed in 9 patients. Decompression alone was performed in all cases; however, 1 patient developed cervical instability requiring an anterior cervical instrumented fusion 5 years later., Conclusions: Decompression without fusion is a safe, reliable surgical option in patients with bow hunter's syndrome. Decompression is performed via a posterior approach for atlantoaxial vertebral artery compression and via an anterior approach for subaxial compression. Long-term complications include cervical instability, which may necessitate internal fixation and fusion., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: To evaluate the use of intraaortic balloon pump (IABP) placement to counter severe cardiac dysfunction after aneurysmal subarachnoid hemorrhage (SAH)., Methods: From August 2006 to October 2011, eight patients (seven women, mean age 47 years ± 5) with aneurysmal SAH underwent IABP placement. The modified Rankin scale (mRS) was used to assess outcome at discharge and long-term follow-up., Results: Most patients presented in poor Hunt & Hess grade (grade III, 25%; grade IV, 62.5%; grade V, 12.5%). Three patients underwent surgical clipping, and five patients underwent endovascular treatment. All patients had severe cardiogenic shock, with a mean ejection fraction of 21%. One patient (12.5%) experienced transient left leg ischemia attributable to the IABP. No patient deaths occurred. At discharge, one patient was moderately disabled (mRS = 3), two patients were moderately to severely disabled (mRS, 4), and five patients were severely disabled (mRS = 5). The seven patients available for long-term follow-up (mean, 11.25 months) showed substantial functional improvements. Two patients exhibited no significant disability (mRS = 1), two patients exhibited only slight disability (mRS = 2), and 3 patients exhibited moderate to severe disability (mRS = 4)., Conclusions: In select patients, particularly young women with poor-grade SAH, balloon-pump counterpulsation may serve as a useful adjunct in the management of severe cardiac dysfunction after SAH. Further investigation is necessary to define the optimal patient population for this technique., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objective: Carotid-cavernous fistulas (CCFs) are pathologic arteriovenous shunts between the carotid artery and cavernous sinus. The resulting venous congestion within the cavernous sinus accounts for the classic ocular symptoms associated with these lesions. Endovascular treatment of CCFs has evolved over time to include a variety of transarterial and transvenous embolization techniques. The present series comprises our institutional experience with the endovascular treatment of CCF., Methods: We reviewed our prospectively maintained clinical database for patients with CCF who were evaluated between December 1995 and August 2012. Clinical and demographic data were extracted from medical records, operative notes, and radiographic reports. Cerebral angiograms were reviewed., Results: The study included 100 (42 direct CCF [dCCF], 58 indirect [iCCF]) patients. Of the 42 patients with dCCF, endovascular treatment was possible in 40 (95%), with an overall 8% morbidity and 2% mortality. Before March 2004, dCCFs were primarily treated with the use of detachable balloons. After the withdrawal of detachable balloons from the market, coil embolization emerged as the first-line treatment. It was accomplished either transarterially or transvenously and often incorporated balloon or stent protection of the parent vessel. After initial treatment, 33 patients (82%) exhibited complete obliteration of their fistula, whereas an additional four (10%) patients demonstrated fistula thrombosis on follow-up angiography. Endovascular access was achieved in 48 (83%) of the 58 patients with iCCF. In this cohort, the morbidity rate was 8%, and there were no deaths. Transvenous approaches were used to treat 88% of these patients and included both transfemoral venous access to the cavernous sinus and direct access through the ophthalmic veins. Immediate fistula occlusion was observed in 37 (77%) patients, and 1 of the 11 patients with a residual fistula progressed to thrombosis on follow-up. Transarterial embolization alone was used in six cases, and five required combined transvenous/transarterial approaches., Conclusions: For dCCF, the lack of availability of detachable balloons led to the adoption of both transarterial and transvenous coil embolization with adjunctive techniques of parent vessel protection. For iCCF, advances in techniques of venous access have facilitated treatment of lesions with restricted venous outflow. Treatment strategies for CCF continue to evolve with advances in endovascular techniques., (Copyright © 2013 Elsevier Inc. All rights reserved.)