Vestibular schwannomas (VS) are slow-growing tumors of the vestibular nerve. Gross total resection (GTR) is recommended for large tumors (> 4 cm), brainstem compression, cranial neuropathy, and hydrocephalus. In select complex cases at our high-volume skull base center, subtotal resection (STR) is pursued for various clinical factors. These patients may require adjuvant radiotherapy (ART) if residual tumor progresses. We sought to evaluate tumor control following STR of VS and identify risk factors of future ART need. A single-center retrospective review (2009–2019) identified patients with VS with complete data who underwent STR without prior treatment. Tumor volumes were extracted from contrast-enhanced T1-weighted volumetric MRI by semi-automated segmentation using 3D Slicer. Clinical and procedural data, including House-Brackmann scores at discharge and 90-day follow-up, were reviewed. Postoperative tumor volumes and progression-free survival (PFS) were calculated. Multivariate logistic regression assessed risk factors for ART. Among 1119 VS patients, 38 (3.4

Background and Objectives : Vestibular schwannomas (VS) are slow-growing tumors of the vestibular nerve. Gross total resection (GTR) is recommended for large tumors (> 4cm), brainstem compression, cranial neuropathy, and hydrocephalus. In select complex cases at our high-volume skull base center, subtotal resection (STR) is pursued for various clinical factors. These patients may require adjuvant radiotherapy (ART) if residual tumor progresses. We sought to evaluate tumor control following STR of VS and identify risk factors of future ART need. Methods : A single-center retrospective review (2009–2019) identified patients with VS with complete data who underwent STR without prior treatment. Tumor volumes were extracted from contrast-enhanced T1-weighted volumetric MRI by semi-automated segmentation using 3D Slicer. Clinical and procedural data, including House-Brackmann scores at discharge and 90-day follow-up, were reviewed. Postoperative tumor volumes and progression-free survival (PFS) were calculated. Multivariate logistic regression assessed risk factors for ART. Results : Among 1119 VS patients, 38 (3.4%) patients underwent STR. Of the STR patients, 15 (39.5%) required ART. Preoperative volumes did not differ significantly. In STR-alone patients, the average residual volume was 15.26±3.54%, while in STR+ART patients the average residual volume was 37.53±12.33% (p<0.001). The smallest residual requiring ART was 23.4%, while the largest residual not requiring ART was 20.6%. Median PFS among ART patients was 29.67 months. On multivariate analysis, percent residual volume independently predicted ART need (AOR 1.28, CI 1.06-2.29, p=0.002 ). Conclusion : STR is viable in select complex VS cases. Residual VS volume ≥20.6% may confer increased risk of progression and necessitate ART. Close postoperative surveillance over 2-3 years is warranted.

BACKGROUND AND OBJECTIVES:Hydrocephalus is a comorbid condition in patients with vein of Galen malformations (VOGMs), and its management is complicated by venous hypertension, elevating surgical risk. Endoscopic third ventriculostomy (ETV) is commonly used for cerebrospinal fluid (CSF) diversion in children, but there are limited available data on its efficacy and safety for patients with VOGM. We aimed to review our experiences with ETV across 2 high-volume centers for VOGM patients with hydrocephalus. METHODS:A two-center retrospective review identified all patients with VOGM who underwent ETV. Demographics, clinical presentation, procedural history, and outcomes were reviewed. ETV success scores were calculated. RESULTS:Twelve patients with VOGM underwent ETV; 66.7% was male, with a median age of 6 months. Seven (58.3%) were still undergoing VOGM embolization before ETV, and 4 had a history of hydrocephalus with acute-on-chronic exacerbation. Eight patients (66.7%) presented with obstructive hydrocephalus because of aqueductal stenosis (58.3%) and with intraventricular hemorrhage without CSF pathway stenosis (8.3%). Three (25.0%) required external ventricular drain placement or fontanelle taps pre-ETV, and choroid plexus cauterization was performed in 4 patients (33.3%). Technical success of ETV was achieved in all cases. One patient experienced venous bleeding at the ventriculostomy site. Postoperative complications occurred in 2 patients: one with transient truncal ataxia and the other with seizure activity, all of which resolved by discharge. At most recent follow-up, 10 patients (83.3%) have minimal residual arteriovenous shunting of their VOGM. The mean ETV success score was 60.8, and 11 patients (91.7%) experienced clinical improvement with ETV patency at the 6-month follow-up. One patient required conversion to a ventriculoperitoneal shunt because of lack of improvement at 6 months. CONCLUSION:This largest-to-date series on VOGM-associated hydrocephalus treated with ETV demonstrates high safety and efficacy across 2 independent high-volume centers. In patients with VOGM demonstrating clinical deterioration secondary to hydrocephalus, ETV with possible choroid plexus cauterization is a viable CSF diversion strategy to consider.

Pediatric arteriovenous malformations (AVM) are rare lesions with significant morbidity and mortality. Presentations may vary widely between the neonatal period, the infantile period, and older age groups. Literature characterizing the incidence of these complex lesions, their symptoms, and overall prognosis in the setting of modern improved endovascular techniques and understanding of pathophysiology is limited. Data from the 2006-2019 HCUP KID database identified 1,224 AVM patients with age less than one year using ICD-9 and ICD-10 codes. Cohorts were stratified by greater or less than 28 days of age to separately assess neonatal AVM patients. Demographics, clinical presentation, comorbidities, mortality, and procedural history were assessed. Brain AVMs were diagnosed in 1 of every 15,160 patients under the age of 1: 504 infants and 600 neonates were identified. Neonates more frequently required non-elective embolizations, while infants received more embolizations and did not require interhospital transfers for care (all p<0.001). Neonatal patients experienced greater mortality (17.5 vs. 2.2%), and were at higher risk of seizures, cardiac failure, pulmonary hypertension, and intraventricular hemorrhage (all p<0.001). Infants more frequently presented with hydrocephalus, intracranial hypertension, developmental delays, hemiplegia/paraplegia, and stroke with or without residual neurological deficit (all p<0.001). Neonates more frequently required ventilatory support and were more likely to receive blood transfusions in surgery, while infants were more likely to receive ventriculoperitoneal shunts and PEG placement (all p<0.001). Though infantile AVMs are a rare disease, neonates and infants continue to demonstrate a wide constellation of emergent symptoms that require timely endovascular embolization and personalized management. Outcomes continue to improve over time as our understanding of the pathophysiology and management of AVMs evolves.

INTRODUCTION:Trigeminal neuralgia (TN) is an uncommon disorder that leads to debilitating pain and interference with daily life. While often attributed to neurovascular compression, limited research has explored the underlying etiology and risk factors for TN. This study uses the National Inpatient Sample (NIS), the largest publicly-available administrative inpatient database in the United States, to examine demographics and comorbidities associated with TN, aiming to identify potential risk factors and vulnerable inpatient populations. METHODS:NIS data from 2016 to 2019 was searched for patients with a primary diagnosis of TN (ICD-10 G50.0). Demographics and comorbidities were identified. A 1:1 propensity match was performed between TN and non-TN patients based on demographics, hospital characteristics, and Charlson Comorbidity Index scores. Multivariable regression was performed to identify factors associated with TN and calculate adjusted odds ratios (OR). RESULTS:The final cohort included 38,300 patients, of whom 19,150 (50.0%) had TN. After matching, TN was significantly associated with multiple sclerosis (p < 0.001), other neurovascular compression disorders (NCD) including glossopharyngeal neuralgia and hemifacial spasm (p < 0.001), stroke (p < 0.001), systemic lupus erythematosus (p = 0.003), hyperlipidemia (p = 0.006), and complex diabetes (p < 0.001). Risk factors with the highest ORs included other NCDs (OR: 60.60, p < 0.001), multiple sclerosis (OR: 8.92, p < 0.001), and lupus (OR: 2.84, p = 0.003). CONCLUSION:TN requiring hospitalization was independently associated with several comorbidities, including multiple sclerosis, lupus, stroke, hyperlipidemia, diabetes, and other NCDs. Notably, this is the first population-level study to identify an association between lupus and TN, highlighting a potential inflammatory component in TN pathophysiology. Prospective studies are warranted to further elucidate these associations.

Seizure is a frequent presenting symptom for patients with newly diagnosed meningiomas. Though many risk factors have been identified, it is unknown whether driver mutations associated with meningioma development also portend increased risk for perioperative seizure in patients with meningiomas. Tumor samples and clinical data were collected from an institutional tissue bank of patients who had a surgical resection of a primary meningioma between 1995 and 2018. The tumor samples were sequenced using next-generation targeted sequencing. Univariable models were used to select for relevant mutations with p-value < 0.20 for inclusion in the multivariate analysis. Multivariable models were built using selected variables and known clinical and demographic correlates of seizures. Of 146 patients with primary cranial meningiomas, 36 (24.7%) patients experienced preoperative seizures and 35 (24.0%) patients experienced postoperative seizures. A total of 16 (11.0%) patients developed both preoperative and postoperative seizures. With multivariable analysis, AKT1 mutation (OR = 4.26, p = 0.04), WHO grade 2 (OR = 12.94, p = 0.04) and convexity location (OR = 3.71, P =0.01) were associated with increased risk for preoperative seizures. Prior preoperative seizure (OR = 4.82, p = 0.003) were significantly associated with increased risk of developing postoperative seizure. For patients experiencing preoperative seizures, need for adjuvant radiation (OR = 28.5, p = 0.048) was significantly associated with increased risk of developing postoperative seizure. We identified AKT1 mutations, WHO grade 2, and convexity location as predictors of preoperative seizures. Prior preoperative seizures portended increased risk of postoperative seizure in patients with primary meningiomas. This analysis may help to inform which patients with newly diagnosed meningiomas may warrant antiepileptic drugs.

BACKGROUND AND OBJECTIVES:Seizure is an observed symptom for patients with newly diagnosed meningiomas. Recent progress has been made in the genomic characterization of meningiomas. However, it is currently unknown whether driver mutations associated with meningioma development also portend increased risk of perioperative seizure. We conducted a single center retrospective clinical and genomic review of patients who underwent primary meningioma resection to understand which mutations were associated with increased risk of perioperative seizure. METHODS:Tumor samples and clinical data were collected from an institutional tissue bank of patients who had a surgical resection of a primary meningioma between 1995 and 2018. Tumor samples were sequenced using next-generation targeted sequencing. Univariable models were used to select for relevant mutations for inclusion in the multivariate analysis. Multivariable models were built using selected variables and known clinical and demographic correlates of seizures. RESULTS:Of 196 sequenced patients in the cohort, 146 patients had primary cranial meningiomas. 36 patients (24.7%) experienced preoperative seizures, and 35 patients (24.0%) experienced postoperative seizures. With multivariable analysis, AKT1 mutation and high serum creatinine were associated with increased odds of preoperative seizures. Increased age at surgery and low preoperative serum bicarbonate were associated with decreased odds of preoperative seizure. Prior preoperative seizure was significantly associated with increased risk of developing postoperative seizure, and meningioma resection surgery was associated with decreased odds of developing postoperative seizure. CONCLUSION:Our study suggests that AKT1 mutation, high serum creatinine, and decreased age at surgery may be predictors of preoperative seizures in primary meningioma patients. In addition, prior preoperative seizures portended increased risk of postoperative seizure in this patient cohort and meningioma resection surgery was protective against the development of postoperative seizure. These analyses may improve treatment paradigms by helping to identify the patients who may benefit from earlier preoperative antiseizure medication usage.

Transarterial embolization of external carotid artery (ECA) branches is increasingly performed for the management of epistaxis, preoperative embolization of head and neck tumors, treatment of dural arteriovenous fistulas, and, more recently, for the treatment of chronic subdural hematoma. As new indications for ECA embolization in the management of conditions like chronic subdural hematoma continue to be identified, it is imperative that interventionalists understand the presence of intricate anastomoses between the extracranial and intracranial arterial systems, which confer significant procedural risks. Failure to account for these connections can result in devastating complications such as stroke, blindness, or cranial nerve injury due to nontarget embolization. This review examines the key anatomical territories of ECA-internal carotid artery anastomoses: the orbital region, petrous-cavernous region, and upper cervical region. These areas, often involving embryological remnants or collateral channels that enlarge in response to pathology, represent potential conduits for inadvertent embolization. We discuss the importance of preprocedural angiography to document anastomosis locations, embolic material selection, special considerations in the context of pathology, and techniques to mitigate risks. Specific considerations for each anatomical region are discussed, with a focus on critical anastomoses, embolization risks, and prevention strategies.

Objectives:This study aimed to identify demographic, clinical, and operative factors of unplanned 30-day readmission following endoscopic transsphenoidal surgery (ETS). Design:Single-center retrospective study. Setting:A tertiary academic medical center based in New York, NY. Participants:A total of 386 adult patients who underwent non-emergent ETS for pituitary adenomas between March 2009 and May 2020. Main Outcome Measures:The primary outcome was 30-day unplanned hospital admission. Clinical and demographic characteristics were analyzed using χ 2 and Student's t -tests. For factors with p -value <0.1, multivariate logistic regression models were constructed to estimate the adjusted odds of 30-day readmission across predictive factors. Results:Of 386 patients who received ETS, 29 (7.5%) patients required readmission within 30 days of discharge. Eleven (2.8%) patients were readmitted for complications related to electrolyte derangements (syndrome of inappropriate antidiuretic hormone, hyponatremia), followed by 5 (1.3%) patients with epistaxis. On multivariate analysis, pituitary microadenomas ( p  = 0.032), transient diabetes insipidus (DI; p  = 0.021), and preoperative visual cranial nerve palsies (CN III/IV/VI; p  = 0.019) were associated with increased odds of 30-day readmission. Conclusion:Patients with pituitary microadenomas, transient DI, and preoperative cranial nerve palsies were at an increased risk for unplanned 30-day readmission after ETS. Dedicated neuroendocrinology involvement is necessary in the postoperative period to reduce readmission risk in these patients. Identification and careful monitoring of these at-risk populations is necessary, as targeted postdischarge care may prevent readmission and improve both patient and hospital outcomes.

As embolization techniques for the management of vein of Galen malformations (VOGM) continue to evolve, aggressive embolization for complete obliteration is increasingly favored. Transvenous embolization with the retrograde pressure cooker technique, involving high volumes of liquid embolic agent (LEA), has gained popularity to achieve complete obliteration. Though clinical outcomes have improved, there is limited discussion regarding the impact of high-volume embolization on the juvenile brain. A 2-year-old boy without previous history of hydrocephalus presented with tri-ventricular hydrocephalus and signs of clinical deterioration 6 days after complete cure of his VOGM by transvenous embolization with Onyx, n-BCA, and coils. The patient was emergently taken for endoscopic third ventriculostomy (ETV), which was successful. On long-term follow-up, the patient did not experience any permanent neurologic deficits and continued to demonstrate progression in milestones. Though embolization is viewed as the appropriate strategy for management of VOGM-related hydrocephalus, patients receiving high-volume LEA embolization may be at increased risk for obstructive hydrocephalus secondary to mass effect even without previous history of hydrocephalus. As guidelines continue to favor aggressive embolization for cure, neurosurgeons should maintain a high degree of suspicion for signs of new-onset hydrocephalus when following VOGM patients after high-volume embolization.

Introduction: Vein of Galen malformations (VOGM) are embryonic choroid plexus-derived arteriovenous malformations which may develop secondary to mosaicism. Sequencing of peripheral whole blood is often ineffective in identifying novel mutations responsible for VOGM development. Whole blood is typically considered to be a transcriptionally homogenous tissue, although vascular microenvironments may impart site-specific transcriptional changes. Here, we investigated whether peripherally collected whole blood samples would yield a different transcriptomic signature compared to targeted blood collection near a biologically active lesion. Methods: Whole blood was prospectively collected from femoral access (peripheral) and catheterized intracranial feeding vessels (intralesional) during endovascular embolization of 8 patients for management of VOGM. All blood samples were matched and collected within the same endovascular procedure. RNA sequencing of 15,730 genes from 23 samples after quality-control was aligned, normalized, and residualized using Rsubread, sva, and limma/voom. Differentially expressed genes (DEGs) were identified between peripheral and intralesional blood draws. Gene set enrichment analysis (GSEA) was conducted using Gene Ontology biological processes and cellular components. Results: 430 genes (196 upregulated, 234 downregulated) were differentially expressed in whole blood collected from intracranial feeders to the VOGM versus the femoral artery. When comparing matched samples, tissue-specific choroid plexus and VOGM-associated genes were significantly upregulated in intralesional whole blood. This included IQUB, a gene involved in ciliary formation and function, expressed at high degrees in the brain in the ventricular ependyma and choroid plexus; UBXN10, a cilium assembly gene which demonstrates body-wide tissue specificity for the choroid plexus; and PTGIS, a nonspecific prostacyclin synthase secreted by neovessels developing in the context of CNS inflammation. Conclusion: We demonstrate the first evidence of differential whole blood transcriptomic signatures by anatomical location. Intracranially collected whole blood of VOGM patients demonstrated upregulation of choroid plexus-specific genes compared to femoral arterial blood collected during the same procedure. Future studies assessing peripheral whole blood transcriptomes should consider the added prognostic value of targeted endovascular blood draws for cell-free molecular profiling.