Search

This meeting abstract was removed due to the OA licensing requirements of this journal. The full abstract is listed here : https://www.svin.org/files/SVIN_2021_Abstracts_for_Web.pdf

This meeting abstract was removed due to the OA licensing requirements of this journal. The full abstract is listed here : https://www.svin.org/files/SVIN_2021_Abstracts_for_Web.pdf

This meeting abstract was removed due to the OA licensing requirements of this journal. The full abstract is listed here : https://www.svin.org/files/SVIN_2021_Abstracts_for_Web.pdf

Hinchazón celular; Edema; Traumatismo cerebral Cellular swelling; Edema; Traumatic brain injury Inflor cel·lular; Edema; Traumatisme cerebral Sulfonylurea receptor 1 (SUR1) is a member of the adenosine triphosphate (ATP)-binding cassette (ABC) protein superfamily, encoded by Abcc8, and is recognized as a key mediator of central nervous system (CNS) cellular swelling via the transient receptor potential melastatin 4 (TRPM4) channel. Discovered approximately 20 years ago, this channel is normally absent in the CNS but is transcriptionally upregulated after CNS injury. A comprehensive review on the pathophysiology and role of SUR1 in the CNS was published in 2012. Since then, the breadth and depth of understanding of the involvement of this channel in secondary injury has undergone exponential growth: SUR1-TRPM4 inhibition has been shown to decrease cerebral edema and hemorrhage progression in multiple preclinical models as well as in early clinical studies across a range of CNS diseases including ischemic stroke, traumatic brain injury, cardiac arrest, subarachnoid hemorrhage, spinal cord injury, intracerebral hemorrhage, multiple sclerosis, encephalitis, neuromalignancies, pain, liver failure, status epilepticus, retinopathies and HIV-associated neurocognitive disorder. Given these substantial developments, combined with the timeliness of ongoing clinical trials of SUR1 inhibition, now, another decade later, we review advances pertaining to SUR1-TRPM4 pathobiology in this spectrum of CNS disease—providing an overview of the journey from patch-clamp experiments to phase III trials. No funding directly supported the writing of this review. R.M.J. is supported by grants from the National Institute of Neurological Disorders and Stroke (NINDS) (K23NS101036; R01NS115815), and the Barrow Neurological Foundation. J.M.S. is supported by grants from the Department of Veterans Affairs (I01RX003060; 1I01BX004652), the Department of Defense (SC170199), the National Heart, Lung and Blood Institute (R01HL082517) and the NINDS (R01NS102589; R01NS105633).

Objective The COVID-19 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 the first patient-centric evaluation of telemedicine in our endovascular neurosurgery practice, covering a 4-month period early in the pandemic. Methods Survey emails after telemedicine visits were sent to all patients who underwent an outpatient telemedicine visit from March 11, 2020, through June 22, 2020, at an endovascular neurosurgery clinic affiliated with a tertiary care center. Results Sixty-five of 140 patients (46%) completed the email survey. Thirty-five of the 65 patients (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. Sixty-one of the 65 patients (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 to 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 neuroendovascular patients expressed satisfaction with their telemedicine visits, and telemedicine will likely play an important role in future outpatient endovascular neurosurgery consultations.

BACKGROUND Coccidioidomycosis is a primarily self-limiting fungal disease endemic to the western United States and South America. However, severe disseminated infection can occur. The authors report a severe case of coccidioidal meningitis that appeared to be a subarachnoid hemorrhage (SAH) on initial inspection. OBSERVATIONS A man in his early 40s was diagnosed with coccidioidal pneumonia after presenting with pulmonary symptoms. After meningeal spread characterized by declining mental status and hydrocephalus, coccidioidal meningitis was diagnosed. The uniquely difficult aspect of this case was the deceptive appearance of SAH due to the presence of multiple aneurysms and blood draining from the patient’s external ventricular drain. LESSONS Coccidioidal infection likely led to the formation of multiple intracranial aneurysms in this patient. Although few reports exist of coccidioidal meningitis progressing to aneurysm formation, patients should be closely monitored for this complication because outcomes are poor. The presence of basal cistern hyperdensities from a coccidioidal infection mimicking SAH makes interpreting imaging difficult. Surgical management of SAH can be considered safe and viable, especially when the index of suspicion is high, such as in the presence of multiple aneurysms. Even if it is unclear whether aneurysmal rupture has occurred, prompt treatment is advisable.

OBJECTIVE Single-position prone lateral lumbar interbody fusion (LLIF) improves the efficiency of staged minimally invasive lumbar spine surgery. However, laterally approaching the lumbar spine, especially L4–5 with the patient in the prone position, could increase the risk of complications and presents unique challenges, including difficult ergonomics, psoas migration, and management of the nearby lumbar plexus. The authors sought to identify postoperative femoral neurapraxia after single-position prone LLIF at L4–5 to better understand how symptoms evolve over time. METHODS This retrospective analysis examined a prospectively maintained database of LLIF patients who were treated by two surgeons (J.S.U. and J.D.T.). Patients who underwent single-position prone LLIF at L4–5 and percutaneous pedicle screw fixation for lumbar stenosis or spondylolisthesis were included if they had at least 6 weeks of follow-up. Outpatient postoperative neurological symptoms were analyzed at 6-week, 3-month, and 6-month follow-up evaluations. RESULTS Twenty-nine patients (16 women [55%]; overall mean ± SD age 62 ± 11 years) met the inclusion criteria. Five patients (17%) experienced complications, including 1 (3%) who had a femoral nerve injury with resultant motor weakness. The mean ± SD transpsoas retractor time was 14.6 ± 6.1 minutes, the directional anterior electromyography (EMG) threshold before retractor placement was 20.1 ± 10.2 mA, and the directional posterior EMG threshold was 10.4 ± 9.1 mA. All patients had 6-week clinical follow-up evaluations. Ten patients (34%) reported thigh pain or weakness at their 6-week follow-up appointment, compared with 3/27 (11%) at 3 months and 1/20 (5%) at 6 months. No association was found between directional EMG threshold and neurapraxia, but longer transpsoas retractor time at L4–5 was significantly associated with femoral neurapraxia at 6-week follow-up (p = 0.02). The only case of femoral nerve injury with motor weakness developed in a patient with a retractor time that was nearly twice as long as the mean time (27.0 vs 14.6 minutes); however, this patient fully recovered by the 3-month follow-up evaluation. CONCLUSIONS To our knowledge, this is the largest study with the longest follow-up duration to date after single-position prone LLIF at L4–5 with percutaneous pedicle screw fixation. Although 34% of patients reported ipsilateral sensory symptoms in the thigh at the 6-week follow-up evaluation, only 1 patient sustained a nerve injury; this resulted in temporary weakness that resolved by the 3-month follow-up evaluation. Thus, longer transpsoas retractor time at L4–5 during prone LLIF is associated with increased ipsilateral thigh symptoms at 6-week follow-up that may resolve over time.

BackgroundStudies have shown an association between surgical treatment volume and improved quality metrics. This study evaluated nationwide results in carotid artery stenting (CAS) procedural readmission rates, costs, and length of stay based on hospital treatment volume.MethodsWe used the Nationwide Readmissions Database for carotid stenosis from 2010 to 2015. Patients receiving CAS were matched based on demographics, illness severity, and relevant comorbidities. Patients were matched 1:1 between low- and high-volume centers using a non-parametric preprocessing matching program to adjust for parametric causal inferences. Nearest-neighbor propensity score matching was performed using logit distance.ResultsLow- and high-volume centers admitted a mean (SD) of 4.68 (3.79) and 25.10 (16.86) patients undergoing CAS per hospital, respectively. Comorbidities were significantly different and initially could not be adequately matched. Because of significant differences in baseline patient population characteristics after attempted matching between low- and high-volume centers, we used propensity adjustment with multivariate analysis. Using this alternative approach, no significant differences were observed between low- and high-volume centers for the presence of any complication, postoperative stroke, postoperative myocardial infarction, and readmission at 30 days.ConclusionIn 1:1 nearest-neighbor matching with a high number of patients, our analysis did not result in well-matched cohorts for the effect of case volume on outcomes. Comparing analytical techniques for various outcomes highlights that outcome disparities may not be related to quality differences based on hospital size, but rather variability in patient populations between low- and high-volume institutions.

BackgroundVasospasm following aneurysmal subarachnoid hemorrhage (SAH) contributes significant morbidity and mortality after brain aneurysm rupture. However, the association between vascular territory of vasospasm and clinical outcome has not been studied. We present a hypothesis-generating study to determine whether the location of vasospasm within the intracranial circulation is associated with functional outcome after SAH.MethodsA retrospective analysis of a prospective, intention-to-treat trial for aneurysmal SAH was performed to supplement trial outcomes with in-hospital angiographic imaging and treatment variables regarding vasospasm. The location of vasospasm and the position on the vessel (distal vs proximal) were evaluated. Modified Rankin scale (mRS) outcomes were assessed at discharge and 6 months, and predictive models were constructed.ResultsA total of 406 patients were included, 341 with follow-up data at 6 months. At discharge, left-sided vasospasm was associated with poor outcome (odds ratio (OR), 2.37; 95% CI, 1.25 to 4.66; P=0.01). At 6 months, anterior cerebral artery (ACA) vasospasm (OR, 3.87; 95% CI, 1.29 to 11.88; P=0.02) and basilar artery (BA) vasospasm (OR, 6.22; 95% CI, 1.54 to 27.11; P=0.01) were associated with poor outcome after adjustment. A model predicting 6-month mRS score and incorporating vasospasm variables achieved an area under the curve of 0.85 and a net improvement in reclassification of 13.2% (PConclusionsIn aneurysmal SAH, left-sided vasospasm is associated with worse discharge functional status. At 6 months, both ACA and BA vasospasm are associated with unfavorable functional status.

A man in his 60s presented with severe ophthalmoparesis and loss of visual acuity in his right eye. He was found to have a giant aneurysm of the cavernous internal carotid artery (ICA). Treatment with a flow diverter was recommended. The aneurysm caused matricidal outflow restriction of the ICA. Microwire and microcatheter access through the aneurysm was challenging, requiring multiple wires, stentriever reduction, and more. Eventually, a construct of 3 Pipeline embolization devices was created across the aneurysm. Troubleshooting access across giant aneurysms is an important part of treatment. Informed consent was obtained for the procedure and for publication. The video can be found here: https://stream.cadmore.media/r10.3171/2022.7.FOCVID2258

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.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.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, P0.001). A linear uptrend was observed for the mean CCI score of patients (R 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.

Background Middle meningeal artery (MMA) embolization for chronic subdural hematomas (cSDHs) has been found to be associated with fewer treatment failures compared to surgical evacuation. The present study compares 30-day emergency department (ED) utilization for patients with cSDHs with and without adjunctive MMA embolization. Methods All patients who presented with a cSDH to a quaternary center from January 1st, 2018 to December 31, 2020 were retrospectively reviewed. Patients were separated into two cohorts: surgery alone and combined surgery with MMA embolization. The surgery only cohort comprised of patients who presented during the first two years of the cohort. The combined surgery and MMA embolization cohort comprised of all patients with a combined treatment during the entire three-year study period. Patients in the combined cohort comprised of planned combined therapies, as well as patients who failed surgery and required MMA embolization. Primary outcome compared was 30-day ED presentation and readmission. Patients with bilateral treatment were analyzed for admission cSDH size. Results Of the 137 patients who met the study criteria, 28 patients (20%) had combined MMA embolization and surgery. In the 28 combined patients, 15 (54%) were planned MMA embolization and 13 (46%) were due to surgical failure. There was no difference between the two cohorts in mean age, gender, admission Glasgow Coma Score (GCS), discharge GCS, comorbidities, or previous trauma. The mean cSDH size on presentation in the surgery alone cohort (N=123, 20.5mm, sD 6.9) was comparable to the combined group (N=32, 18.7mm, sD 4.5) (p=0.16). A significant higher percentage of patients in the surgery alone (N=32, 29%) cohort presented within 30-days to the ED compared to combined MMA embolization with surgery (N=2, 7%) (p=0.02). There was no significant difference in readmission rates between the surgery alone (N=16, 15%,) and combined cohort (N=1, 4%) (p=0.11). Nine patients (8%) in the surgery alone cohort were readmitted due to significant reaccumulation/residual compared to only one patient (4%) in the combined group (p=0.4). Conclusion Combined MMA embolization and surgical evacuation in cSDH patients appears to be associated with decrease 30-day ED utilization compared to surgery alone. Disclosures J. Catapano: None. C. Nguyen: None. V. Srinivasan: None. C. Rutledge: None. T. Cole: None. J. Baranoski: None. S. Elmasry: None. M. Lawton: None. A. Jadhav: None. A. Ducruet: None. F. Albuquerque: None.

BackgroundFew reports discuss variables associated with improved outcomes after middle meningeal artery (MMA) embolization for chronic subdural hematomas (cSDHs). We analyzed radiographic evidence of cSDH clearance after MMA embolization to elucidate optimal techniques, hematoma clearance rates, and suitable length of follow-up.MethodsPatients who underwent MMA embolization for cSDH from January 1, 2018 through December 31, 2020 were analyzed. Patient characteristics, demographics, and technical procedural details were examined. Outcomes for cSDHs analyzed included complete or near-complete resolution at 30, 90, and 180 days following embolization. A multivariable logistic regression analysis identified variables predictive of rapid clearance and resolution of hematomas at 90 days.ResultsThe study cohort comprised 66 patients with 84 treated cSDHs. The mean (SD) cSDH size differed significantly at 30-day (8.8 (4.3) mm), 90-day (3.4 (3.0) mm), and 180-day (1.0 (1.7) mm) follow-up (pConclusionAlthough 63% of cSDHs with MMA embolization had complete or near-complete resolution by 90 days post-procedure, 92% reached this stage by 180 days. Therefore, 90-day follow-up may be insufficient to determine the effectiveness of MMA embolization for cSDHs, particularly compared with surgical evacuation alone. Also, distal MMA penetration may be associated with more rapid hematoma clearance.

Brain arteriovenous malformations (AVMs) are characterized by a high-pressure, low-resistance vascular nidus created by direct shunting of blood from feeding arteries into arterialized veins, bypassing intervening capillaries. AVMs pose a risk of spontaneous rupture because the vessel walls are continuously exposed to increased shear stress and abnormal flow phenomena, which lead to vessel wall inflammation and distinct morphologic changes. The annual rupture rate is estimated at 2%, and once an AVM ruptures, the risk of rerupture increases 5-fold. The ability of AVMs to grow, regress, recur, and undergo remodeling shows their dynamic nature. Identifying the underlying cellular and molecular pathways of AVMs not only helps us understand their natural physiology but also allows us to directly block vital pathways, thus preventing AVM development and progression. Management of AVMs is challenging and often necessitates a multidisciplinary approach, including neurosurgical, endovascular, and radiosurgical expertise. Because many of these procedures are invasive, carry a risk of inciting hemorrhage, or are controversial, the demand for pharmacologic treatment options is increasing. In this review, we introduce novel findings of cellular and molecular AVM physiology and highlight key signaling mediators that are potential targets for AVM treatment. Furthermore, we give an overview of syndromes associated with hereditary and nonhereditary AVM formation and discuss causative genetic alterations.

Traumatic brain injury (TBI) is associated with one-third of all deaths from trauma. Preinjury exposure to cardiovascular drugs may affect TBI outcomes. Angiotensin-converting enzyme inhibitors (ACEIs) exacerbate brain cell damage and worsen functional outcomes in the laboratory setting. β-blockers (BBs), however, appear to be associated with reduced mortality among patients with isolated TBI. Examine the association between preinjury ACEI and BB use and clinical outcome among patients with isolated TBI. A retrospective cohort study of patients age ≥ 40 years admitted to an academic level 1 trauma center with isolated TBI between January 2010 and December 2014 was performed. Isolated TBI was defined as a head Abbreviated Injury Scale (AIS) score ≥ 3, with chest, abdomen, and extremity AIS scores ≤ 2. Preinjury medication use was determined through chart review. All patients with concurrent BB use were initially excluded. In-hospital mortality was the primary measured outcome. Over the 5-year study period, 600 patients were identified with isolated TBI who were naive to BB use. There was significantly higher mortality (P = .04) among patients who received ACEI before injury (10 of 96; 10%) than among those who did not (25 of 504; 5%). A multivariate stepwise logistic regression analysis revealed a threefold increased risk of mortality in the ACEI cohort (P

External ventricular drains (EVDs) are often placed emergently for patients with hydrocephalus, which carries a risk of hemorrhage. Rarely, rupture of a pseudoaneurysm originating from an EVD placement precipitates such a hemorrhage. An EVD was placed in a patient with a ruptured left posterior communicating artery aneurysm who later underwent endovascular coil embolization. On post-bleed day 20, a distal right anterior cerebral artery pseudoaneurysm along the EVD tract ruptured, which was successfully treated via clip-wrapping. Although EVD-associated pseudoaneurysms are rare, they have a high propensity for rupture. Early treatment of these lesions should be considered to prevent neurologic deterioration.

Objective Postoperative peri-lead edema (PLE) is a poorly understood complication of deep brain stimulation (DBS), which has been described sporadically in patients presenting with profound and often delayed symptoms. We performed a prospective evaluation of patients undergoing DBS to determine the frequency of and identify risk factors for PLE. Methods Patients underwent DBS electrode placement by a single physician. Postoperative magnetic resonance imaging (MRI) was performed approximately 6 weeks after the operation in asymptomatic subjects and analyzed for presence of PLE. All symptomatic subjects underwent MRI at the time of presentation. Data regarding index disease, preoperative medical issues, operative technique, and intraoperative variables were collected and statistically analyzed. Results A total of 191 leads were placed in 102 subjects; 15 patients (14.7%) demonstrated PLE. Seven patients (6.9%) presented with symptoms related to PLE, most often altered mental status or neurologic deficit. Many of the MRI findings were profound, with PLE sometimes several centimeters in diameter. No statistically significant difference was found between PLE-positive and normal subjects when analyzing multiple variables, including presence of vascular disease, hypertension, anticoagulant/antiplatelet use, electrode target, index disease, unilateral versus bilateral lead placement, number of brain penetrations, and presence or absence of microelectrode recording. Conclusions Patients with postoperative PLE can present with severe symptoms or can be asymptomatic and go undiagnosed. Because of the delayed-onset potential, PLE may be more common than previously reported. No clear risk factors have been identified; therefore, further studies and increased clinical vigilance are paramount for improving comprehension and possible prevention of PLE.

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

BackgroundThis study aims to define the proportion of Medicare neuroendovascular procedures performed by different specialists from 2013 to 2019, map the geographic distribution of these specialists, and trend reimbursement for these procedures.MethodsThe Medicare Provider Utilization Database was queried for recognized neuroendovascular procedures. Data on specialists and their geographic distribution were tabulated. Reimbursement data were gathered using the Physician Fee Schedule Look-Up Tool and adjusted for inflation using the United States Bureau of Labor Statistics’ Consumer Price Index Inflation calculator.ResultsThe neuroendovascular workforce in 2013 and 2019, respectively, was as follows: radiologists (46% vs 44%), neurosurgeons (45% vs 35%), and neurologists (9% vs 21%). Neurologists increased proportionally (p=0.03). Overall procedure numbers increased across each specialty: radiology (360%; p=0.02), neurosurgery (270%; pConclusionsThe number of neuroendovascular procedures and specialists increased, with neurologists becoming more predominant. Reimbursement decreased. Coordination among neuroendovascular specialists in terms of training and practice location may maximize access to acute care.

A variety of pathogenic mechanisms have been described in the formation, maturation, and rupture of brain arteriovenous malformations (bAVMs). While the understanding of bAVMs has largely been formulated based on animal models of rare hereditary diseases in which AVMs form, a new era of “omics” has permitted large-scale examinations of contributory genetic variations in human sporadic bAVMs. New findings regarding the pathogenesis of bAVMs implicate changes to endothelial and mural cells that result in increased angiogenesis, proinflammatory recruitment, and breakdown of vascular barrier properties that may result in hemorrhage; a greater diversity of cell populations that compose the bAVM microenvironment may also be implicated and complicate traditional models. Genomic sequencing of human bAVMs has uncovered inherited, de novo, and somatic activating mutations, such as KRAS, which contribute to the pathogenesis of bAVMs. New droplet-based, single-cell sequencing technologies have generated atlases of cell-specific molecular derangements. Herein, the authors review emerging genomic and transcriptomic findings underlying pathologic cell transformations in bAVMs derived from human tissues. The application of multiple sequencing modalities to bAVM tissues is a natural next step for researchers, although the potential therapeutic benefits or clinical applications remain unknown.

Dural arteriovenous fistulas (DAVFs) are benign but may present with life-threatening hemorrhage or symptoms of venous hypertension (eg, progressive myelopathy).1-3 DAVFs follow well-described anatomic patterns.4 The marginal sinus is located between the layers of the dura, circumferentially around the foramen magnum. It communicates with the basal venous plexus of the clivus anteriorly and the occipital sinus posteriorly.5,6 Arterial supply to the dura in this region that fistulizes into the sinus arises from meningeal branches from the V3 or V4 segments. A man in his early 70s presented with chronic neck pain and new onset of left arm and face paresthesias. He had brisk patellar reflexes bilaterally and a marginal sinus DAVF, with numerous dilated veins around the cisterna magna, causing dorsal cervicomedullary compression. Angiography confirmed the diagnosis of DAVF rather than arteriovenous malformation. Endovascular embolization was considered, but surgery was preferable because of poor transarterial access. The patient underwent left far lateral craniotomy and C1 laminectomy with exposure of the condylar fossa. The dura was carefully elevated laterally, revealing a network of dilated tortuous veins, with multiple points of fistulous connection within the dura emanating in a large venous varix. Indocyanine green videoangiography showed the aberrant flow dynamics. The fistulous point was occluded with aneurysm clips on the venous side, then cauterized and interrupted. The patient was discharged within 3 d of surgery and had full resolution of symptoms at 6 wk. Angiography confirmed complete obliteration of the DAVF. The patient provided written informed consent for treatment. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.

Outcomes for octogenarians and nonagenarians after an aneurysmal subarachnoid hemorrhage (aSAH) are particularly ominous, with mortality rates well above 50%. The present analysis examines the neurologic outcomes of patients ≥ 80 years of age treated for aSAH.A retrospective review was performed of all aSAH patients treated at Barrow Neurological Institute from January 1, 2003, to July 31, 2019. Patients were placed in 2 groups by age, 80 vs ≥ 80 years. The ≥ 80-year-old group of octogenarians and nonagenarians was subsequently analyzed to compare treatment modalities. Poor neurologic outcome was defined as a modified Rankin Scale (mRS) score of 2.During the study period, 1418 patients were treated for aSAH. The mean (standard deviation) age was 55.1 (13.6) years, the mean follow-up was 24.6 (40.0) months, and the rate of functional independence (mRS 0-2) at follow-up was 54% (751/1395). Logistic regression analysis found increasing age strongly associated with declining functional independence (RAge is a significant prognostic indicator of functional outcomes and mortality after aSAH. Most octogenarians and nonagenarians with aSAH will become severely disabled or die.

Although the full transcavernous approach affords extensive mobilization of the oculomotor nerve (OMN) for exposure of the basilar apex and interpeduncular cistern region, this time-consuming procedure requires substantial dural dissection along the anterior middle cranial fossa.To quantify the extent to which limited middle fossa dural elevation affects the carotid-oculomotor window (C-OMW) surgical area during transcavernous exposure after OMN mobilization.Four cadaveric specimens were dissected bilaterally to study the C-OMW area afforded by the transcavernous exposure. Each specimen underwent full and limited transcavernous exposure and anterior clinoidectomy (1 procedure per side; 8 procedures). Limited exposure was defined as a dural elevation confined to the cavernous sinus. Full exposure included dural elevation over the gasserian ganglion, extending to the middle meningeal artery and lateral middle cranial fossa.The C-OMW area achieved with the limited transcavernous exposure, compared with full transcavernous exposure, provided significantly less total area with OMN mobilization (22 ± 6 mm2 vs 52 ± 26 mm2, P = .03) and a smaller relative increase in area after OMN mobilization (11 ± 5 mm2 vs 36 ± 13 mm2, P = .03). The increase after OMN mobilization in the C-OMW area after OMN mobilization was 136% ± 119% with a limited exposure vs 334% ± 216% with a full exposure.In this anatomical study, the full transcavernous exposure significantly improved OMN mobilization and C-OMW area compared with a limited transcavernous exposure. If a transcavernous exposure is pursued, the difference in the carotid-oculomotor operative corridor area achieved with a limited vs full exposure should be considered.

BackgroundThe middle meningeal artery (MMA) has been implicated in chronic headaches, but no studies have examined the relationship between MMA embolization and headaches.MethodsPatients 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.ResultsOf 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], pConclusionIn 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.

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

Introduction: Transradial arterial access (TRA) for cerebral diagnostic angiography (DSA) is associated with reduced access-site complications compared with transfemoral access (TFA), though concerns about increased procedure time and radiation exposure may slow its adoption. Objective: To examine “radial-first” cerebral angiography by measuring TRA rates of success and fluoroscopy time and comparing to TFA. Methods: We examined 500 consecutive cerebral angiograms during the first full year of “radial-first” adoption, recording patient and procedural characteristics including intended and performed access sites, fluoroscopy time per vessel catheterized, and outcomes of the procedure. Results: Of 500 angiograms done over a nine-month period at a single center, 431 (86.2%) of cases were successfully performed via TRA. There was one case of temporary neurologic deficit in the TRA group, and none in the TFA group (n=1, 0.2% TRA vs. n=0, 0.05 TFA, p=0.8). Vascular access-site complications were lower in the TRA group than TFA (n=2, 0.4% TRA vs. n=2, 4.7% TFA, p=0.04). There was no difference in the number of cases successfully performed via TRA in the first half of the study compared with the second (n=215, 86.0% vs. n=216, 86.4%, p=0.90). Fluoroscopy time decreased from the first half of the study to the second half for TRA performance(5.0±3.9 min/vessel vs. 3.4±3.5 min/vessel, p Conclusions: Among angiograms performed during the first full year of “radial first” implementation, 86% were performed successfully using TRA. TRA efficiency continued to improve beyond the initial learning curve, exceeding that of TFA after 150 angiograms. Concerns about length of procedure or radiation exposure should not be barriers to TRA adoption.

Background and Purpose: Transradial access (TRA) for neuroendovascular procedures is increasing in prevalence, although numerous procedures are still performed using transfemoral access (TFA). Some cardiology studies have suggested the safety benefits of TRA at a patient level may be offset at a population level by a paradoxical increase in TFA vascular access site complications (VASCs) associated with radial adoption, the so-called “radial paradox.” We studied the effect of TRA adoption on TFA performance and VASC rates in neuroendovascular procedures. Methods: Data were collected for all neuroendovascular procedures performed over a 10-month period by trainees after implementation of a radial-first paradigm at a single center. Results: Over the study period, 1,084 procedures were performed, including 689 (63.6%) via TRA and 395 (36.4%) via TFA. In comparison to TRA, TFA cases were performed in older patients (TFA 63 ±15 vs. TRA 56 ±16), were predominantly male (TFA 52.9% vs. TRA 38.6%), used larger sheath sizes (≥7 French, TFA 56.6% vs. TRA 2.3%), were more often emergent (TFA 37.7% vs. TRA 1.1%), and used tPA administration (TFA 15.3% vs. TRA 0%) (p.99) complications. After multivariate analysis, independent predictors of any VASC included TFA (OR 2.8, 95% CI 1.1-7.4) and use of dual antiplatelets (OR 4.2, 95% CI 1.6—11.1). Conclusions: TFA remains an essential route for neuroendovascular procedures, accounting for 36.4% of cases under a radial-first paradigm. TFA is disproportionately performed in patients undergoing procedures with an increased-risk for VASCs, though the minor and major VASC rates are comparable to historical controls. TFA proficiency may still be achieved in radial-first training without an increase in femoral complications.

In cases of extreme vertebrobasilar dolichoectasia, padding the cranial nerves (CNs) (microvascular decompression [MVD]) and clip-assisted sling transposition of the tortuous artery (macrovascular decompression [MaVD]) may be ineffective because the sling does not reduce the redundancy. Transposition may not decompress the nerves or may kink the artery. An alternative solution is needed.To introduce the "binder ring" bypass as a novel solution to this unusual macrovascular compression problem.The binder ring denotes the opening and closing of the offending vascular loop with standard bypass techniques with the artery transected, rerouted lateral to the CNs, and reanastomosed. An example case study is presented for a 72-year-old man whose severe vertebral artery tortuosity could not be relieved by MVD or MaVD. His pathology was exposed with an extended retrosigmoid craniotomy, the V4 segment was transected, the free ends were mobilized lateral to CN VII/VIII, and an end-to-end reanastomosis was performed with intraluminal suturing.The example binder ring bypass was patent angiographically, and the patient experienced immediate and lasting symptom relief without complications.The binder ring bypass applies standard bypass techniques to macrovascular compression but represents a significant escalation in technical challenges relative to traditional techniques. Patient tolerance to temporary arterial occlusion during reanastomosis depends on the location of the compressive arterial loop and the anatomy of collateral circulation. The binder ring bypass should be used as a last resort after medical therapy and MaVD techniques fail and performed only by neurosurgeons with advanced bypass skills.

Study design A consecutive series of patients who underwent minimally invasive spinal surgery by a single surgeon at a high-volume academic medical center were studied. Objective The objective of this study was to identify the prevalence, radiographic features, and clinical characteristics of patients who require unplanned secondary decompressive laminectomy or foraminotomy after lateral lumbar interbody fusion (LLIF). Summary of background data LLIF indirectly decompresses the spinal canal, lateral recess, and neural foramen when properly performed. However, indirect decompression relies on endplate integrity, reasonable bone quality, and sufficient contralateral release so that ligament distraction can occur. Some patients have insufficient decompression, resulting in persistent axial low back pain or radiculopathy. Methods Patients undergoing LLIF for radiculopathy or refractory low back pain were enrolled in a prospective registry. Preoperative and postoperative imaging, clinical presentation, and operative reports were reviewed from this registry. Results During registry collection, 122 patients were enrolled (220 lumbar levels treated), with nearly even representation between men (64/122, 52.5%) and women (58/122, 47.5%). Overall, right-sided lumbar spinal approaches (74/122, 60.7%) were more common. Ultimately, 4.1% (five of 122) of patients required unplanned direct decompressive laminectomy or foraminotomy because of refractory radiculopathy and persistent radiographic evidence of compression at the index LLIF level. All patients for whom indirect decompression failed were men who underwent stand-alone LLIF and had radiculopathy contralateral to the side of the LLIF approach. Most patients (59.8%, 73/122) had evidence of graft subsidence (grade 0 or 1) or osteoporosis. Conclusion We report a 4.1% rate of return to the operating room for failed indirect decompression after LLIF for refractory radiculopathy. Graft subsidence and osteoporosis were common in these patients. All five patients who required secondary decompressive laminectomy or foraminotomy underwent stand-alone primary LLIF, and the persistent radiculopathy was consistently contralateral to the initial side of the LLIF approach.Level of Evidence: 4.

OBJECTIVE The incidence and severity of stroke are disproportionately greater among Black patients. In this study, the authors sought to examine clinical outcomes among Black versus White patients after mechanical thrombectomy for stroke at a single US institution. METHODS All patients who underwent mechanical thrombectomy at a single center from January 1, 2014, through March 31, 2020, were retrospectively analyzed. Patients were grouped based on race, and demographic characteristics, preexisting conditions, clinical presentation, treatment, and stroke outcomes were compared. The association of race with mortality was analyzed in multivariable logistic regression analysis adjusted for potential confounders. RESULTS In total, 401 patients (233 males) with a reported race of Black (n = 28) or White (n = 373) underwent mechanical thrombectomy during the study period. Tobacco use was more prevalent among Black patients (43% vs 24%, p = 0.04), but there were no significant differences between the groups with respect to insurance, coronary artery disease, diabetes, illicit drug use, hypertension, or hyperlipidemia. The mean time from stroke onset to hospital presentation was significantly greater among Black patients (604.6 vs 333.4 minutes) (p = 0.007). There were no differences in fluoroscopy time, procedural success (Thrombolysis in Cerebral Infarction grade 2b or 3), hospital length of stay, or prevalence of hemicraniectomy. In multivariable analysis, Black race was strongly associated with higher mortality (32.1% vs 14.5%, p = 0.01). The disparity in mortality rates resolved after adjusting for the average time from stroke onset to presentation (p = 0.14). CONCLUSIONS Black race was associated with an increased risk of death after mechanical thrombectomy for stroke. The increased risk may be associated with access-related factors, including delayed presentation to stroke centers.

BackgroundOmeprazole is a common proton pump inhibitor that interferes with the hepatic activation of clopidogrel and potentially reduces its platelet-inhibitory effect. Omeprazole has been shown to increase P2Y12 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.MethodsAll patients with placement of a flow-diverting device for treatment of an intracranial aneurysm at a tertiary institution from January 1, 2014, to December 31, 2018, were retrospectively analyzed. Inclusion criteria included documented clopidogrel administration, available P2Y12 levels, and thorough documentation of administration of other medications, including omeprazole.ResultsA total of 138 patients met the inclusion criteria. Sixteen patients (12%) were receiving omeprazole and clopidogrel at treatment. P2Y12 reactivity was significantly greater in the omeprazole cohort (mean P2Y12 level, 250 P2Y12 reaction units (PRU)) than in the control cohort (mean P2Y12 level, 112PRU) (P12 level >180 PRU in the omeprazole cohort (14 of 16 [88%] vs 24 of 122 [20%]; PConclusionOmeprazole was associated with a significant increase in the mean P2Y12 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 Although rare, cavernous malformations (CMs) of the optic nerve and anterior optic pathway (optic pathway cavernous malformations [OPCMs]) can occur, as described in several single case reports in the literature. Objective To describe the technical aspects of microsurgical management of CMs of the optic pathway on the basis of an extensive single-center experience and review of the literature. Methods A systematic literature review was performed to augment an earlier review, using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. In addition, an institutional database was searched for all patients undergoing surgical resection of OPCMs. Patient information, surgical technique, and clinical and radiographic outcomes were assessed. Results Since the previous report, 14 CMs were resected at this institution or by the senior author at another institution. In addition, 34 cases were identified in the literature since the systematic review in 2015, including some earlier cases that were not discussed in the previous report. Most OPCMs were resected via pterional, orbital-pterional, and orbitozygomatic craniotomies. Visual outcomes were similar to those in earlier reports, with 70% of patients reporting stable to normal vision postoperatively. Conclusion OPCMs can occur throughout the anterior visual pathway and may cause significant symptoms. Surgery is feasible and should be considered for OPCMs presenting to a surface of the nerve. Favorable results can be obtained with resection, although optimal results are obtained with patients who present with milder symptoms without longstanding damage to the optic apparatus.

High-risk dural arteriovenous fistulas, defined as fistulas with cortical venous reflux, can be treated with both endovascular and open surgical techniques. However, in challenging cases in which surgical risk is high and traditional endovascular access via transarterial or transvenous routes is not obtainable, hybrid open surgical and endovascular techniques can be used. This chapter reviews cases from the literature exploring these novel approaches with illustrative examples and discusses the indications and nuances of performing hybrid surgical and endovascular procedures for these challenging lesions in the modern neuroendovascular era.

Modern cerebrovascular bypass surgery uses either extracranial-intracranial (EC-IC) or intracranial-intracranial (IC-IC) approaches. Compared with EC-IC bypasses, IC-IC bypasses allow neurosurgeons to safely address tumors, aneurysms, and other lesions using shorter grafts that are well matched to the size of recipient vessels. Fewer than 100 articles have been published on IC-IC bypasses compared with more than 1000 on EC-IC bypasses. This study examined the increase of interest and innovation in IC-IC bypass.PubMed and Web of Science were searched using keywords specific to IC-IC bypass, yielding 717 articles supplemented with 36 reports from other databases and gray literature. The articles were reviewed, and 98 articles were selected for further evaluation. Final articles were categorized as innovations or retrospective studies. Publication metrics were passed through an analytic program to assess statistical measures of growth.The number of publications describing innovations (n = 52) and retrospective studies (n = 46) in IC-IC surgical techniques increased exponentially (RAs more work is undertaken on IC-IC bypasses, it is critical for knowledge to be shared through research, collaboration, publication, and early teaching within residency training programs. This field has increased exponentially in the past 2 decades and has yet to reach an inflection point, indicating possible additional interest and growth over time.