National multicentered retrospective review of clinical and intraoperative factors associated with the development of cerebellar mutism after pediatric posterior fossa tumor resection.

BACKGROUND: Cerebellar mutism (CM) is characterized by a significant loss of speech in children following posterior fossa (PF) surgery. The biological origin of CM remains unclear and is the subject of ongoing debate. Significant recovery from CM is less likely than previously described despite rigorous multidisciplinary neuro-rehabilitational efforts. METHODS: A national multi-centered retrospective review of all children undergoing PF resection in four midsized Canadian academic pediatric institutions was undertaken. Patient, tumor and surgical factors associated with the post-operative development of CM were reviewed. Retrospective identification of PF surgery patients including those developing and those that did not (internal control). RESULTS: The study identified 258 patients across the 4 centers between 2010 and 2020 (mean age 6.73 years; 42.2% female). Overall, CM was experienced in 19.5% of patients (N = 50). Amongst children who developed CM histopathology included medulloblastoma (35.7%), pilocytic astrocytoma (32.6%) and ependymoma (17.1%). Intraoperative impression of adherence to the floor of the 4th ventricle was positive in 36.8%. Intraoperative abrupt changes in blood pressure and/or heart rate were identified in 19.4% and 17.8% of cases. The clinical resolution of CM was rated to be complete, significant resolution, slight improvement, no improvement and deterioration in 56.0%, 8.0%, 20.0%, 14.0% and 2.0%, respectively. In the cohort of children who experienced post-operative CM as compared to their no-CM counterpart, proportionally more tumors were felt to be adherent to the floor of the 4th ventricle (56.0% vs 49.5%), intraoperative extent of resection was a GTR (74% vs 68.8%) and changes in heart rate were noted (≥ 20% from baseline) (26.0% vs 15.9%). However, a multiple regression analysis identified only abrupt changes in HR (OR 5.97, CI (1.53, 23.1), p = 0.01) to be significantly associated with the development of post-operative CM. CONCLUSION: As a devastating surgical complication after posterior fossa tumor surgery with variable clinical course, identifying and understanding the operative cues and revising intraoperative plans that optimizes the child's neurooncological and clinical outcome are essential.

Recent Trends in Neurosurgery Career Outcomes in Canada.

BACKGROUND: As with other specialties, Royal College of Physicians and Surgeons of Canada (RCPSC) trainees in Neurosurgery have anecdotally had challenges securing full-time employment. This study presents the employment status, research pursuits, and fellowship choices of neurosurgery trainees in Canadian programs. METHODS: RCPSC neurosurgery trainees (n = 143) who began their residency training between 1998 and 2008 were included in this study. Associations between year of residency completion, research pursuits, and fellowship choice with career outcomes were determined by Fisher's exact test (p < 0.05, statistical significance). RESULTS: In 2015, 60% and 26% of neurosurgery trainees had permanent positions in Canada and the USA, respectively. Underemployment, defined as locum and clinical associate positions, pursuit of multiple unrelated fellowships, unemployment, and career change to non-surgical career, was 12% in 2015. The proportion of neurosurgery trainees who had been underemployed at some point within 5 years since residency completion was 20%. Pursuit of in-folded research (MSc, PhD, or non-degree research greater than 1 year) was significantly associated with obtaining full employment (94% vs. 73%, p = 0.011). However, fellowship training was not significantly associated with obtaining full employment (78% vs. 75%, p = 1.000). CONCLUSIONS: Underemployment in neurosurgery has become a significant issue in Canada for various reasons. Pursuit of in-folded research, but not fellowship training, was associated with obtaining full employment.

Tendances récentes au Canada en ce qui regarde les possibilités d'emploi en neurochirurgie.Contexte: À l'instar d'autres stagiaires de la médecine spécialisée, des stagiaires en neurochirurgie membres du Collège royal des médecins et des chirurgiens du Canada (CRMCC) ont dit éprouver, selon des données empiriques, des difficultés à obtenir un emploi à plein temps. Cette étude entend présenter la situation professionnelle des stagiaires inscrits dans des programmes canadiens en neurochirurgie ainsi que leurs activités de recherche et leurs choix en matière de bourses de recherche postdoctorale. Méthodes : Des stagiaires membres du CRMCC ayant entrepris leur résidence entre 1998 et 2008 (n = 143) ont été inclus dans cette étude. Les liens pouvant exister entre l'année de résidence complétée, les activités de recherche, les choix en matière de bourses de recherche postdoctorale et les possibilités d'emploi ont été déterminés au moyen du test exact de Fisher (p < 0,05 ; signification statistique). Résultats : En 2015, 60 % des stagiaires en neurochirurgie du Canada disaient compter sur un poste permanent alors qu'ils étaient 26 % à affirmer la même chose aux États-Unis. Le sous-emploi, défini comme par des postes de suppléant (locum) et de clinicien adjoint, par l'obtention de plusieurs bourses de recherche postdoctorale sans liens apparents, par le chômage et par un changement d'orientation excluant la chirurgie, atteignait 12 % la même année. La proportion de stagiaires disant avoir été sous-employés à un moment ou un autre au cours des 5 années de leur résidence était par ailleurs de 20 %. Le fait de mener un projet de recherche dans le cadre de sa résidence (M.Sc., Ph.D. ou en dehors des cycles supérieurs pendant au moins 12 mois) était clairement associé à l'obtention d'un emploi à temps plein (94 % contre 73 % ; p = 0,011). Cela dit, une formation offerte à la suite de l'obtention d'une bourse de recherche postdoctorale n'a pas été associée de manière notable à l'obtention d'un emploi à temps plein (78 % contre 75 % ; p = 1,000). Conclusions : Le sous-emploi en neurochirurgie est désormais un enjeu important au Canada, et ce, pour toutes sortes de raisons. Contrairement aux formations liées à l'obtention d'une bourse de recherche postdoctorale, le fait de mener un projet de recherche régulier a été associé à l'obtention d'un emploi à temps plein.

Stent anchor technique to reduce microcatheter loop for stent-assisted coiling of anterior communicating artery aneurysm.

Stent-assisted coiling offers a potential solution for coil embolization of broad-based aneurysms. Challenges associated with navigating a microcatheter beyond these aneurysms sometimes require looping the microcatheter within the aneurysm dome. Reducing microcatheter loops within domes can be difficult, and anchor techniques have been described, including balloon anchor, stent-retriever anchor, and stent anchor techniques. The authors present a patient requiring stent-assisted coiling of an anterior communicating artery aneurysm in whom a stent anchor technique was used to reduce a microcatheter loop within an aneurysm dome before coil embolization. Postembolization angiographic runs showed complete coil occlusion of the aneurysm with approximately 35% packing density.The video can be found here: https://youtu.be/zHR1ZOArUro.

Demographics, Interests, and Quality of Life of Canadian Neurosurgery Residents.

BACKGROUND: Neurosurgical residents face a unique combination of challenges, including long duty hours, technically challenging cases, and uncertain employment prospects. We sought to assess the demographics, interests, career goals, self-rated happiness, and overall well-being of Canadian neurosurgery residents. METHODS: A cross-sectional survey was developed and sent through the Canadian Neurosurgery Research Collaborative to every resident enrolled in a Canadian neurosurgery program as of April 1, 2016. RESULTS: We analyzed 76 completed surveys of 146 eligible residents (52% response rate). The median age was 29 years, with 76% of respondents being males. The most popular subspecialties of interest for fellowship were spine, oncology, and open vascular neurosurgery. The most frequent self-reported number of worked hours per week was the 80- to 89-hour range. The majority of respondents reported a high level of happiness as well as stress. Sense of accomplishment and fatigue were reported as average to high and overall quality of life was low for 19%, average for 49%, and high for 32%. Satisfaction with work-life balance was average for 44% of respondents and was the only tested domain in which significant dissatisfaction was identified (18%). Overall, respondents were highly satisfied with their choice of specialty, choice of program, surgical exposure, and work environment; however, intimidation was reported in 36% of respondents and depression by 17%. CONCLUSIONS: Despite a challenging residency and high workload, the majority of Canadian neurosurgery residents are happy and satisfied with their choice of specialty and program. However, work-life balance, employability, resident intimidation, and depression were identified as areas of active concern.

Operative Landscape at Canadian Neurosurgery Residency Programs.

Background Currently, the literature lacks reliable data regarding operative case volumes at Canadian neurosurgery residency programs. Our objective was to provide a snapshot of the operative landscape in Canadian neurosurgical training using the trainee-led Canadian Neurosurgery Research Collaborative. METHODS: Anonymized administrative operative data were gathered from each neurosurgery residency program from January 1, 2014, to December 31, 2014. Procedures were broadly classified into cranial, spine, peripheral nerve, and miscellaneous procedures. A number of prespecified subspecialty procedures were recorded. We defined the resident case index as the ratio of the total number of operations to the total number of neurosurgery residents in that program. Resident number included both Canadian medical and international medical graduates, and included residents on the neurosurgery service, off-service, or on leave for research or other personal reasons. RESULTS: Overall, there was an average of 1845 operative cases per neurosurgery residency program. The mean numbers of cranial, spine, peripheral nerve, and miscellaneous procedures were 725, 466, 48, and 193, respectively. The nationwide mean resident case indices for cranial, spine, peripheral nerve, and total procedures were 90, 58, 5, and 196, respectively. There was some variation in the resident case indices for specific subspecialty procedures, with some training programs not performing carotid endarterectomy or endoscopic transsphenoidal procedures. CONCLUSIONS: This study presents the breadth of neurosurgical training within Canadian neurosurgery residency programs. These results may help inform the implementation of neurosurgery training as the Royal College of Physicians and Surgeons residency training transitions to a competence-by-design curriculum.

Valproic Acid treatment after experimental subarachnoid hemorrhage.

INTRODUCTION: Subarachnoid hemorrhage (SAH) can result in significant brain injury. Valproic acid (VPA), a widely-used anti-epileptic drug, was investigated as a possible neuroprotective drug in a prechiasmatic injection model of SAH in mice. METHODS: Mice were randomized to the following experimental groups: SAH, SAH + VPA, Sham, and Sham + VPA. VPA (400 mg/kg) or saline was administered within 30 min of SAH induction and every 12 h thereafter for 48 h. Neurobehavioral assessments using the modified Garcia Score were conducted at 24 and 48 h. Brain injury was assessed at 48 h with fluoro-jade b and caspase-3/NeuN histo- and immunohistochemistry. Vasospasm was assessed in the MCA branches using hematoxylin & eosin histology. RESULTS: SAH mice treated with VPA appeared to have improved neurobehavioral assessments at both 24 and 48 h compared to untreated SAH mice. VPA treatment in SAH mice also significantly decreased the number of degenerating neurons on fluoro-jade b staining. In VPA-treated SAH mice, there was a trend toward a decrease in the number of apoptotic neurons on caspase-3/NeuN immunohistochemistry. VPA did not significantly affect vasospasm. CONCLUSION: This study demonstrated that VPA improves neurological outcome and decreases brain injury in a mouse model of SAH.

Primary Malignant Meningeal Melanoma Complicated by Cerebral Venous Sinus Thrombosis: An Illustrative Case With a Systematic Review of the Literature.

Melanocytic tumors of the central nervous system (CNS) such as meningeal melanoma are exceedingly rare tumours derived from leptomeningeal melanocytes. We report an illustrative case of a previously healthy 47-year-old male who presented with tonic-clonic seizure. Magnetic resonance imaging (MRI) with contrast demonstrated a homogenously enhancing right temporal extra-axial lesion. The patient was stabilized on anti-epileptic medications and dexamethasone prior to proceeding with complete surgical resection of the lesion. Intraoperatively, the lesion was heavily pigmented with invasion of the surrounding dura and skull. Histopathology revealed a poorly differentiated neoplasm with nuclear atypia and melanin-containing cells with strong SOX10 and variable S100 positivity. Computed tomography (CT) of the chest, abdomen, and pelvis showed no metastatic disease, and molecular profiling was negative including absent BRAF mutation. He began checkpoint inhibitor therapy and subsequently developed cerebral venous sinus thrombosis managed with anticoagulation. Sixteen months post-operatively, he was neurologically intact, working full-time, and had resumed immunotherapy. We systematically reviewed the literature on primary intracranial malignant melanoma (PIMM) with the goal of understanding the prognosis and best treatment options for this disease. Our systematic review produced 82 articles (118 unique cases) of PIMM. The average age at diagnosis was 45.9 years (95% CI:42.9-48.9), and headache (54.2%) was the most common initial presentation. Eighty-nine percent of patients had primary surgical resection, and 41.0% of these individuals experienced a recurrence with a mean time to recurrence of 19.6 months (95% CI:6.95-32.23). Adjuvant therapy was administered in 65.7% of surgically resected patients; including radiotherapy, chemotherapy, immunotherapy, or a combination. In summary, PIMM is a rare tumour that can appear radiographically similar to meningioma. The results of our systematic review demonstrate that surgical resection remains the mainstay of therapy for best long-term prognosis.

Learning curves for transradial access versus transfemoral access in diagnostic cerebral angiography: a case series.

BACKGROUND: The perception of a steep learning curve associated with transradial access has resulted in its limited adoption in neurointervention despite the demonstrated benefits, including decreased access-site complications. OBJECTIVE: To compare learning curves of transradial versus transfemoral diagnostic cerebral angiograms obtained by five neurovascular fellows as primary operator. METHODS: The first 100-150 consecutive transradial and transfemoral angiographic scans performed by each fellow between July 2017 and March 2020 were identified. Mean fluoroscopy time per artery injected (angiographic efficiency) was calculated as a marker of technical proficiency and compared for every 25 consecutive procedures performed (eg, 1-25, 26-50, 51-75). RESULTS: We identified 1242 diagnostic angiograms, 607 transradial and 635 transfemoral. The radial cohort was older (64.3 years vs 62.3 years, p=0.01) and demonstrated better angiographic efficiency (3.4 min/vessel vs 3.7 min/vessel, p=0.03). For three fellows without previous endovascular experience, proficiency was obtained between 25 and 50 transfemoral angiograms. One fellow achieved proficiency after performing 25-50 transradial angiograms; and the two other fellows, in <25 transradial angiograms. The two fellows with previous experience had flattened learning curves for both access types. Two patients experienced transient neurologic symptoms postprocedure. Transradial angiograms were associated with significantly fewer access-site complications (3/607, 0.5% vs 22/635, 3.5%, p<0.01). Radial-to-femoral conversion occurred in 1.2% (7/607); femoral-to-radial conversion occurred in 0.3% (2/635). Over time, the proportion of transradial angiographic procedures increased. CONCLUSION: Technical proficiency improved significantly over time for both access types, typically requiring between 25 and 50 diagnostic angiograms to achieve asymptomatic improvement in efficiency. Reduced access-site complications and decreased fluoroscopy time were benefits associated with transradial angiography.

Optimal Glucose Target After Aneurysmal Subarachnoid Hemorrhage: A Matched Cohort Study.

BACKGROUND: Hyperglycemia has been associated with poor outcomes in patients with aneurysmal subarachnoid hemorrhage (aSAH). However, there remains debate as to what optimal glucose targets should be in this patient population. OBJECTIVE: To assess whether we could identify an optimal glucose target for patients with aSAH. METHODS: We performed a post hoc analysis of the "clazosentan to overcome neurological ischemia and infarction occurring after subarachnoid hemorrhage" trial data set. Patients had laboratory results drawn daily for the entirety of their intensive care unit stay. Maximum blood glucose levels were assessed for a relationship with unfavorable outcomes using multiple logistic regression analysis. Maximum blood glucose levels were dichotomized based on the Youden index, which identified a maximum level of <9.2 mmol/L as the optimal cut point for prediction of unfavorable outcomes. Nearest neighbor matching was used to assess the relationship between maintaining glucose levels below the cut point and unfavorable functional outcomes (defined as a modified Rankin score of >2 at 3 mo post-aSAH). The matching was performed after calculation of a propensity score based on identified predictors of outcome and glucose levels. RESULTS: Three hundred eighty-nine patients were included in the matched analysis. Propensity scores were balanced on both the covariates and outcomes of interest. There was a significant average treatment effect (-0.143: 95% confidence interval -0.267 to -0.019) for patients who maintained glucose levels <9.2 mmol/L. CONCLUSION: Maintaining glucose levels below the identified cut point was associated with a decreased risk for unfavorable outcomes in this retrospective matched study.

Carotid endarterectomy versus stenting: a meta-analysis of randomized trials.

BACKGROUND: A meta-analysis of randomized controlled trials (RCTs) was conducted to update the available evidence on the safety and efficacy of carotid endarterectomy (CEA) versus carotid artery stenting (CAS) in the treatment of carotid artery stenosis. METHODS: A comprehensive search was performed of MEDLINE, EMBASE, CENTRAL, bibliographies of included articles and past systematic reviews, and abstract lists of recent scientific conferences. For each reported outcome, a Mantel-Haenszel random-effects model was used to calculate odds ratios (ORs) and 95% confidence intervals (CI). The I2 statistic was used as a measure of heterogeneity. RESULTS: Twelve RCTs enrolling 6,973 patients were included in the meta-analysis. Carotid artery stenting was associated with a significantly greater odds of periprocedural stroke (OR 1.72, 95% CI 1.20 to 2.47) and a significantly lower odds of periprocedural myocardial infarction (OR 0.47, 95% CI 0.29 to 0.78) and cranial neuropathy (OR 0.08, 95% CI, 0.04 to 0.16). The odds of periprocedural death (OR 1.11, 95% CI 0.56 to 2.18), target vessel restenosis (OR 1.95, 95% CI 0.63 to 6.06), and access-related hematoma were similar following either intervention (OR 0.60, 95% CI 0.30 to 1.21). CONCLUSIONS: In comparison with CEA, CAS is associated with a greater odds of stroke and a lower odds of myocardial infarction. While the results our meta-analysis support the continued use of CEA as the standard of care in the treatment of carotid artery stenosis, CAS is a viable alternative in patients at elevated risk of cardiac complications.

Spontaneous Spinal Subarachnoid Hemorrhage from a Ruptured Radiculopial Artery Aneurysm.

BACKGROUND: Spontaneous spinal subarachnoid hemorrhage is an uncommon entity and is even rarer when secondary to intraspinal ruptured aneurysm. The clinical presentation of these cases usually includes back pain and headache; however, we report a unique case in which the patient became acutely paraplegic. CASE DESCRIPTION: A 54-year-old woman initially presented with thunderclap headache and interscapular pain. There was no evidence of subarachnoid hemorrhage on noncontrast computed tomography of the head, but lumbar puncture revealed xanthochromia-positive cerebrospinal fluid. Subsequent computed tomography angiography identified a small right superior hypophyseal aneurysm. The patient then became acutely paraplegic during neurosurgical assessment in the emergency department. Urgent magnetic resonance imaging revealed extensive intradural hemorrhage in the cervicothoracic region, prompting emergent surgical decompression. At surgery, this hemorrhage was noted in a subarachnoid location, but no specific source was identified. Postoperative spinal digital subtraction angiography revealed an intraspinal aneurysm of the posterior spinal circulation involving the left T2 radiculopial artery, which was resected in a subsequent uneventful operation within the same hospital admission. CONCLUSIONS: This unique clinical case highlights a rare cause of spontaneous acute paralysis and further demonstrates the safety of obliterating an intraspinal aneurysm via operative resection.

Preoperative Embolization of Fisch Grades II-IVa Juvenile Nasopharyngeal Angiofibromas: Transarterial Embolization in the Age of Onyx.

Objective The current mainstay treatment for juvenile nasopharyngeal angiofibromas (JNAs) is surgical resection, but embolization of primary feeding arteries through endovascular transarterial and direct tumoral puncture embolizations with various agents has been described. We describe a single institutional experience with JNA embolization utilizing Onyx (Medtronic, Dublin, Ireland). Methods A retrospective records review was performed to identify patients who underwent embolization for devascularization of Fisch grades II-IVa JNA (tumor extension beyond the sphenopalatine region) before surgical resection between 2010 and 2019. Fluoroscopy time, grade, intraoperative blood loss, and clinical follow-up data were compiled. Tumor devascularization percentage was calculated using ImageJ software (public domain, BSD-2) by measuring the ratio of preoperative and postoperative embolization tracing. Results Five consecutive patients (ages 12-16 years [average 14 years]; all male) with JNAs underwent preoperative transarterial embolizations performed under general anesthesia. All patients presented with epistaxis; two also presented with headaches. Fisch grades were II in two patients, IIIa in two, and IVa in one. The patient with the grade IVa lesion underwent direct transtumoral puncture and Onyx embolization. The mean percentage of all tumor devascularizations postembolization was 86.0±9.7%.Complete resection 24-48 hours postembolization was obtained for grades II and IIIa lesions with <700 mL blood loss. No embolization-related complications and no clinical sequelae were present in the five cases after embolization. Conclusion In our experience, Onyx embolization of JNAs was safely conducted with adequate tumor penetration beyond the sphenopalatine region through transarterial routes.

Coil Occlusion of Right M2 Fusiform Aneurysm After Balloon-Test Occlusion: 2-Dimensional Video.

We present a 73-year-old man with an incidental right M2 fusiform aneurysm demonstrating growth on serial noninvasive imaging over 5 years (Video 1). After multidisciplinary conference review, the decision was to proceed with intracranial balloon-test occlusion (BTO) followed by coil occlusion if the patient passed this test or by trap and bypass if the patient failed this test. With the patient under moderate conscious sedation, a transfemoral 8F approach was used with positioning of a TracStar 95-cm 088 guide catheter (Imperative Care, Campbell, California, USA) into the distal right cervical ICA. We positioned a Scepter 4-mm × 10-mm compliant dual-lumen balloon microcatheter (MicroVention, Alisa Viejo, California, USA) into the proximal M2. The patient passed the 30-minute BTO including a 15-minute hypotensive challenge with nitroprusside infusion. Our goal was to occlude the aneurysm from distal to proximal for precise thrombosis. A Phenom 17 150-cm microcatheter (Medtronic, Dublin, Ireland) separate from the Scepter balloon microcatheter was positioned in the distal portion of the aneurysm. Coil occlusion was successfully performed with an assortment of complex and helical coils. Sluggish anterograde flow was seen distal to the aneurysm with prominent retrograde filling of the distal right MCA territory via pial collaterals from the right PCA. The patient tolerated the procedure well and was discharged the following day neurologically intact. Six-month follow-up diagnostic angiogram confirmed complete occlusion of the aneurysm. This is the first published video using the elegant approach of intracranial BTO followed by coil occlusion for an intracranial fusiform aneurysm using a dual-lumen balloon microcatheter.

Gene expression profiling of brain endothelial cells after experimental subarachnoid haemorrhage.

Subarachnoid haemorrhage (SAH) is a type of hemorrhagic stroke that is associated with high morbidity and mortality. New effective treatments are needed to improve outcomes. The pathophysiology of SAH is complex and includes early brain injury and delayed cerebral ischemia, both of which are characterized by blood-brain barrier (BBB) impairment. We isolated brain endothelial cells (BECs) from mice subjected to SAH by injection of blood into the prechiasmatic cistern. We used gene expression profiling to identify 707 unique genes (2.8% of transcripts, 403 upregulated, 304 downregulated, 24,865 interrogated probe sets) that were significantly differentially expressed in mouse BECs after SAH. The pathway involving prostaglandin synthesis and regulation was significantly upregulated after SAH, including increased expression of the Ptgs2 gene and its corresponding COX-2 protein. Celecoxib, a selective COX-2 inhibitor, limited upregulation of Ptgs2 in BECs. In this study, we have defined the gene expression profiling of BECs after experimental SAH and provide further insight into BBB pathophysiology, which may be relevant to other neurological diseases such as traumatic brain injury, brain tumours, ischaemic stroke, multiple sclerosis, and neurodegenerative disorders.

Complete flow control using transient concurrent rapid ventricular pacing or intravenous adenosine and afferent arterial balloon occlusion during transvenous embolization of cerebral arteriovenous malformations: case series.

BACKGROUND: There are no reports that describe complete flow control using concurrent transient rapid ventricular pacing or intravenous (IV) adenosine and afferent arterial balloon flow arrest to aid transvenous embolization of cerebral arteriovenous malformations (AVM). We describe our experience with the use of this technique in patients undergoing transvenous AVM embolization. METHODS: Consecutive patients in whom transvenous embolization was attempted at our institute between January 2017 and July 2019 were included. Anatomical AVM features, number of embolization stages, technique of concurrent transient rapid ventricular pacing and afferent arterial balloon flow arrest, complications, and clinical and radiological outcomes were recorded and tabulated. RESULTS: Transvenous AVM embolization was attempted in 12 patients but abandoned in two patients for technical reasons. Complete embolization was achieved in 10 patients, five of whom had infratentorial AVMs. All 10 had a single primary draining vein. Rapid ventricular pacing was used in nine cases; IV adenosine injection was used in one case to achieve cardiac standstill. Complete AVM nidus obliteration was achieved with excellent neurologic outcome in nine cases, with transvenous embolization alone in two cases, and with staged transarterial followed by transvenous embolization in the others. Two patients developed hemorrhagic complications intraprocedurally. One patient was managed conservatively and the other operatively with AVM excision and hematoma evacuation; both made an excellent recovery without any neurologic deficits at 3 months. CONCLUSION: Complete flow control using concurrent transient rapid ventricular pacing with afferent arterial balloon flow arrest technique is safe and feasible for transvenous embolization of select AVMs.

Endovascular management of radial artery loop for neuroangiography: Case series.

BACKGROUND: Radial loops are rare congenital radial artery anomalies that may pose a significant challenge to successful transradial neuroangiography. In this case series, we describe the anatomy and frequency of radial artery loops and provide a technique for successful navigation of this anatomic anomaly. METHODS: We reviewed our database of radial diagnostic or interventional neuroangiographic procedures to identify cases in which a radial loop was encountered during the procedure. The loop pattern, the presence of an associated recurrent radial artery branch, navigation technique, and procedure-related complications were recorded. A descriptive analysis was performed. RESULTS: A total of 997 transradial approach procedures were performed over a 9-month period. A radial loop was identified in 10 (1.0%) patients. The average age was 68.6 ± 14.3 years. A microcatheter advanced over a microwire was used to navigate the loop and avoid entry into the recurrent branch. A diagnostic neuroangiographic procedure was performed successfully in 8 cases and an intervention was performed successfully in 1 case. A 360° loop was present in 2 of these cases. In each case, transradial access was performed successfully. In 1 other diagnostic case, transradial access was aborted, and the femoral artery was accessed to perform the procedure. CONCLUSIONS: A radial loop was present in 1% of the cases in this series. Our technical results suggest that this anomaly should not be considered a contraindication to transradial neuroangiography because the procedure was successfully performed in most (9 of 10) cases using a microcatheter system to navigate the loop.

Transradial access for flow diversion of intracranial aneurysms: Case series.

BACKGROUND: Transradial access for neurointerventions offers advantages of fewer access-site complications, reduced procedure time, and greater patient comfort over transfemoral access. Data about transradial access for flow diversion are limited. We share our early experience with transradial access for flow diversion in a relatively large case series. METHODS: Consecutive patients who underwent Pipeline embolization device (Medtronic) deployment via transradial access were included in the study, irrespective of location and laterality of the intracranial aneurysm. The cases were performed between July 2016 and October 2019. Demographics, aneurysm characteristics, and procedure-related details (including catheter systems used) were recorded and statistically evaluated. RESULTS: Thirty-five transradial flow diversion procedures were attempted in 32 patients, of which 33 procedures were successful. In two cases involving left common carotid artery and internal carotid artery access, guide catheter herniation into the aortic arch led to abandonment of transradial access in favor of transfemoral access. The most common aneurysm locations in the transradial access procedures were the posterior communicating artery (n = 7), ophthalmic artery (n = 7), and superior hypophyseal artery (n = 7). Most transradial access procedures (66.7%) were performed using a biaxial catheter system. 6-French Benchmark (Penumbra) and Phenom 27 (Medtronic) were the most commonly utilized guide- and microcatheters, respectively. One patient had intraprocedural subarachnoid hemorrhage. No access-site complications occurred. CONCLUSION: This study demonstrates safety and feasibility of transradial access for Pipeline embolization device deployment and shows the versatility of this approach for different catheter systems. Tortuosity and acute angulation of the left common carotid artery and internal carotid artery were associated with approach failure.

Safety and feasibility of ulnar artery access for neuroangiography and neurointervention: a case series.

BACKGROUND: Radial access has become popular among neurointerventionalists because it has favorable risk profiles compared with femoral access. Difficulties in accessing or navigating the radial artery have been viewed as a reason to convert to femoral access, but ulnar artery access may prevent complications associated with transfemoral procedures. OBJECTIVE: To evaluate the safety and feasibility of ulnar access for neurointerventions and diagnostic neuroangiographic procedures. METHODS: Consecutive patients who underwent diagnostic angiography or neurointerventional procedures via ulnar access between July 1, 2019 and April 15, 2020 were included. Data recorded were demographics, procedure indication, devices, technique, and complications. Descriptive analysis was performed. RESULTS: Ulnar artery access was obtained for 21 procedures in 18 patients (mean age 70.3±7.8 years; nine men). Procedures included 13 diagnostic angiograms and eight neurointerventions (3 left middle meningeal artery embolization, 1 of which was aborted; 2 carotid artery stenting; 2 angioplasty; 1 mechanical thrombectomy for in-stent thrombosis). A right-sided approach with ultrasound guidance was used for all cases except one. Indications included small caliber radial artery (n=9), radial artery occlusion (n=10), and radial artery preservation for potential bypass (n=2). A 5-French slender sheath was used for diagnostic angiography; a 6-French slender sheath was used for neurointerventions. No case required conversion to femoral access. Two patients had minor hematomas after the procedure; one other had ulnar artery occlusion on 30-day ultrasonography. CONCLUSION: Ulnar access is safe and feasible for diagnostic and interventional neuroangiographic procedures. It provides a useful alternative to radial access, potentially avoiding complications associated with femoral access.

A nationwide prospective multicenter study of external ventricular drainage: accuracy, safety, and related complications.

OBJECTIVE: External ventricular drainage (EVD) catheters are associated with complications such as EVD catheter infection (ECI), intracranial hemorrhage (ICH), and suboptimal placement. The aim of this study was to investigate the rates of EVD catheter complications and their associated risk factor profiles in order to optimize the safety and accuracy of catheter insertion. METHODS: A total of 348 patients with urgently placed EVD catheters were included as a part of a prospective multicenter observational cohort. Strict definitions were applied for each complication category. RESULTS: The rates of misplacement, ECI/ventriculitis, and ICH were 38.6%, 12.2%, and 9.2%, respectively. Catheter misplacement was associated with midline shift (p = 0.002), operator experience (p = 0.031), and intracranial length (p < 0.001). Although mostly asymptomatic, ICH occurred more often in patients receiving prophylactic low-molecular-weight heparin (LMWH) (p = 0.002) and those who required catheter replacement (p = 0.026). Infectious complications (ECI/ventriculitis and suspected ECI) occurred more commonly in patients whose catheters were inserted at the bedside (p = 0.004) and those with smaller incisions (≤ 1 cm) (p < 0.001). ECI/ventriculitis was not associated with preinsertion antibiotic prophylaxis (p = 0.421), catheter replacement (p = 0.118), and catheter tunneling length (p = 0.782). CONCLUSIONS: EVD-associated complications are common. These results suggest that the operating room setting can help reduce the risk of infection, but not the use of preoperative antibiotic prophylaxis. Although EVD-related ICH was associated with LMWH prophylaxis for deep vein thrombosis, there were no significant clinical manifestations in the majority of patients. Catheter misplacement was associated with operator level of training and midline shift. Information from this multicenter prospective cohort can be utilized to increase the safety profile of this common neurosurgical procedure.