Faculty Bibliography

BACKGROUND:Glioblastoma intramedullary spinal cord metastasis (GISCM) is a rare sequela of high-grade astrocytoma and glioblastoma multiforme (GBM). Discrete intramedullary spinal cord metastases are less common than spinal leptomeningeal spread and may follow a more indolent course. Once identified as GISCM, palliative maximal safe resection of the tumor may be considered to alleviate neurological symptoms. Reports describing the surgical management of these rare lesions, including the use of emerging technologies that may aid in maximal safe resection, are sparse. A further understanding is also required regarding the course of disease and factors contributing to mortality in GISCM. METHODS:We reviewed the intraoperative management and clinical course of three patients treated for GISCM at our institution between 2015 and 2024. We additionally conducted a PRISMA-guided systematic literature review of PubMed Central, MEDLINE, and Bookshelf databases through May 26th, 2025, including original patient reports of GISCM from cranial astrocytoma or GBM. The disease course, management strategies, and causes of mortality in previously reported cases were analyzed. RESULTS:Our institutional cohort had a mean time to spinal metastasis of 26.2 months from diagnosis of cranial disease (range 17.5-40.5 months), with a mean survival of 9.2 months following maximal safe resection of extramedullary components (range 7-12 months). In two cases, intraoperative Stimulated Raman Histology (SRH) was employed to facilitate the rapid identification of metastatic GBM, thereby influencing surgical strategy. In one case, 5-aminolevulinic acid (5-ALA) was used to differentiate between tumor and spinal cord parenchyma, facilitating maximal safe debulking without neurological injury. Literature review identified 38 prior reported cases of GISCM, with a median time to spinal diagnosis of 11.0 months and a median survival of 3.5 months thereafter. The cause of death in the review cohort often involved multiple factors, and when analyzed for contributing factors to death, 38.7% involved cranial progression, 38.7% involved progression of spinal disease, and 29.0% involved medical complications. Gait ataxia at presentation was associated with shorter survival in review patients, potentially reflecting advanced disease with extramedullary cord compression. CONCLUSION/CONCLUSIONS:GISCM represents an entity distinct from leptomeningeal disease and may be managed in conjunction with recurrent cranial disease. Surgical debulking is a technically feasible strategy that can be safely facilitated using tools employed in the management of intracranial GBM, facilitating maximal safe resection without compromising survival.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Normal pressure hydrocephalus (NPH) is characterized by the classic triad of cognitive decline, gait instability, and urinary incontinence in the setting of ventriculomegaly with normal intracranial pressure. Cerebrospinal fluid diversion is the current standard treatment, yet it carries a risk of overdrainage, resulting in subdural hematoma or hygroma. Different valves have been developed to mitigate this risk, yet consensus remains unclear regarding optimal valve for NPH. METHODS:We performed a retrospective cohort study on all patients with NPH who underwent cerebrospinal fluid shunting or revision between January 2014 and September 2025 at our institution. Demographic, clinical, and radiological data were collected from the electronic health record. Kaplan-Meier survival analysis, univariate logistic regression, and multivariate modeling were used to identify predictors of subdural collections and the need for surgical treatment. RESULTS:Since our change in practice from the Integra NPH Low Flow Valve (Low Flow OSV) to other valves in 2022, we observed a rise in symptomatic subdural collections. Programmable valves were associated with a markedly increased 1-year risk of both subdural collection formation and need for surgical intervention compared with the Low Flow OSV. Overall, Certas and Strata valves demonstrated higher rates of subdural collections requiring surgery than the Low Flow OSV (14.6% vs 2.1%, P < .001; 10.5% vs 2.1%, P = .005, respectively). On multivariate analysis, both the Strata and Certas valves were independently associated with increased odds of developing any subdural collection and necessitating surgery. Vascular disease and dual antiplatelet therapy also increased risk. CONCLUSION/CONCLUSIONS:In this large single-center cohort study, programmable valves, specifically the Certas and Strata, were associated with an increased rate and severity of subdural collections compared with the Low Flow OSV. The use of low-flow designs may mitigate complications for the NPH population, and the use of lower programmable valve settings should be carefully considered.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Red blood cell transfusions are commonly required in pediatric cranial vault remodeling (CVR); however, they carry risks and potential complications. This study evaluates the evidence on perioperative blood conservation agents assessing their efficacy in optimizing and reducing transfusion requirements in CVR. METHODS:A systematic review was conducted using PubMed/MEDLINE, Scopus, Embase, Web of Sciences, and Google Scholar according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to assess articles discussing blood conservation agents in pediatric CVR. A network meta-analysis compared the effectiveness of different agents including tranexamic acid (TXA), aminocaproic acid (ACA), aprotinin, erythropoietin (EPO), and iron. RESULTS:Sixteen studies analyzing 1072 patients with a mean age of 15.6 months and weight of 8.78 kg were included. The most reported craniosynostosis subtypes were sagittal (30.2%) and metopic (13.8%). TXA and ACA were independently associated with lower transfusion rates and volumes compared with placebo (ACA: odds ratio [OR], 0.25; 95% CI, 0.08-0.80; TXA: OR, 0.17; 95% CI, 0.07-0.42). Combination therapy with TXA + EPO + iron (OR: 0.004, 95% CI: 0.002-0.10) or ACA + EPO (OR: 0.04, 95% CI: 0.01-0.32) were associated with reductions in transfusion rates. Network meta-analysis ranking revealed TXA + EPO + iron (Surface Under the Cumulative Ranking [SUCRA]: 98.90%) and ACA + EPO (SUCRA: 75.41%) as the most effective treatments for reducing transfusion rates. While TXA was associated with significant reductions in blood loss compared with placebo (standard mean difference: -1.26, 95% CI: -1.97 to -0.56), ACA ranked highest for blood loss reduction (ACA: SUCRA, 84.58% vs TXA: SUCRA, 72.43%). Combination of TXA + EPO + iron was associated with significantly reduced hospital length of stay (standard mean difference: -1.00, 95% CI: -1.71 to -0.29). No treatment significantly affected the duration of surgery, and there were no reported treatment-associated thromboembolic events. CONCLUSION/CONCLUSIONS:Our meta-analysis reveals that TXA + ACA reduce red blood cell transfusion rates and volumes, with TXA + EPO + iron and ACA + EPO being most effective. This highlights the superiority of combination therapies and underscores the need for structured multimodal protocols in perioperative blood conservation for pediatric CVR.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Adult biomechanical studies suggest a significant reduction in flexion-extension motion after occipitocervical and atlantoaxial fusion. Anecdotal experience in children suggests a lower magnitude of reduction in motion after these procedures, but high-quality quantitative assessments of this motion have not yet been performed. As such, the aim of this study was to determine the magnitude of reduction in cervical spine flexion-extension after O-C2 and C1-2 fusion in pediatric patients. METHODS:The Pediatric Spine Study Group international registry was queried for patients aged 21 years or younger who underwent O-C2 or C1-2 instrumentation and fusion. Patients with cervical spine flexion-extension radiographs preoperatively and ≥6 months postoperatively were included. Flexion, extension, and overall range of motion (ROM) of the cervical spine were measured on radiographs using McGregor line and the inferior endplate of C7. RESULTS:In total, 34 patients were included, with 19 undergoing index O-C2 and 15 undergoing index C1-2 stabilization. The mean age was 9.3 ± 4.5 years with average follow-up of 3.5 ± 2.6 years. The most common etiologies were syndromic (n = 20) and congenital (n = 9). Patients undergoing O-C2 fusion had reduced neck extension (80° vs 69.6°, P = .003) and overall ROM (92.9° vs 80°, P = .002) after stabilization, but no significant reduction in flexion (-12.9° vs -10.4°, P = .324). After C1-2 fusion, there was no significant reduction in overall ROM (85.0° vs 77.5°, P = .079), extension (70.5° vs 63.4°, P = .120), or flexion (-14.6° vs -14.0°, P = .831). CONCLUSION/CONCLUSIONS:In this cohort, children undergoing O-C2 stabilization had a 13.9% reduction in flexion-extension motion of the cervical spine, primarily due to a reduction in extension. There may be a smaller reduction in flexion-extension motion after stabilization in children when compared with adult studies. Further studies with video analysis including axial rotation and lateral bending will be necessary to comprehensively quantify cervical spine motion after fusion across the occipitocervical and atlantoaxial junctions.

PURPOSE/OBJECTIVE:To identify clinical variables associated with ventricular shunt infection and shunt failure in pediatric hydrocephalus. METHODS:Patients ≤ 18 years treated with ventricular shunts between 2013 and 2024 were identified from one institution's electronic medical record. Children with a confirmed diagnosis of hydrocephalus and ≥ 6 months of postoperative follow-up were included. Primary and revision shunt surgeries were included. Records were manually reviewed for clinical variables. Statistical analyses were performed using R (version 4.2.3). RESULTS:The dataset included 474 surgeries, 146 primary and 328 revisions, undergone by 226 patients. Infection necessitating removal of a previously placed shunt occurred following 3.59% (17/474) of cases. Discharge in ≤ 4 days had a 75% lower relative risk for infection compared to stays > 4 days (1.5% vs. 6% 100-day infection risk; p = 0.011). Patients who underwent revision surgeries for shunt infections were more likely to experience subsequent infections in the first 100 days postoperatively than those revised for other causes (2.42% vs. 21.05%; p < 0.0001). Patient characteristics associated with shunt failure during the 10-year study included younger age (median age: 2.23 years in those with failure vs. 6.62 years in those without; p < 0.0002) and lower weight (median weight: 11.8 kg vs. 20.3 kg; p < 0.0002) at the time of admission. Congenital hydrocephalus (OR = 1.86; p = 0.0045) and aqueductal stenosis (OR = 1.75; p = 0.025) were also associated with shunt failure. CONCLUSIONS:Length of stay > 4 days and previous shunt infection are associated with an increased risk of infection after shunt surgery. These findings are important to consider when counseling pediatric patients and during postoperative monitoring.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Hydrocephalus after Gamma Knife® stereotactic radiosurgery (SRS) for vestibular schwannomas is a rare but manageable occurrence. Most series report post-SRS communicating hydrocephalus in about 1% of patients, thought to be related to a release of proteinaceous substances into the cerebrospinal fluid. While larger tumor size and older patient age have been associated with post-SRS hydrocephalus, the influence of baseline ventricular anatomy on hydrocephalus risk remains poorly defined. METHODS:A single-institution retrospective cohort study examining patients who developed symptomatic communicating hydrocephalus after undergoing Gamma Knife® SRS for unilateral vestibular schwannomas from 2011 to 2021 was performed. Patients with prior hydrocephalus and cerebrospinal fluid diversion or prior surgical resection were excluded. Baseline tumor volume, third ventricle width, and Evans Index (EI)-maximum width of the frontal horns of the lateral ventricles/maximum internal diameter of the skull-were measured on axial postcontrast T1-weighted magnetic resonance imaging. RESULTS:A total of 378 patients met the inclusion criteria; 14 patients (3.7%) developed symptomatic communicating hydrocephalus and 10 patients (2.6%) underwent shunt placement and 4 patients (1.1%) were observed with milder symptoms. The median age of patients who developed hydrocephalus was 69 years (IQR, 67-72) and for patients younger than age 65 years, the risk was 1%. For tumor volumes <1 cm3, the risk of requiring shunting was 1.2%. The odds of developing symptomatic hydrocephalus were 5.0 and 7.7 times higher in association with a baseline EI > 0.28 (P = .024) and tumor volume >3 cm3 (P = .007), respectively, in multivariate analysis. Fourth ventricle distortion on pre-SRS imaging was significantly associated with hydrocephalus incidence (P < .001). CONCLUSION/CONCLUSIONS:Patients with vestibular schwannoma with higher baseline EI, larger tumor volumes, and fourth ventricle deformation are at increased odds of developing post-SRS hydrocephalus. These patients should be counseled regarding risk of hydrocephalus and carefully monitored after SRS.

BACKGROUND:Aneurysmal bone cysts (ABCs) are slow-growing, expansile bone tumors most often observed in the long bones and lumbar and thoracic spine. Anterior column ABCs of the spine are rare, and few cases have described their surgical management, particularly for lesions with extension into the odontoid process and the bilateral C2 pedicles. In the present case, the authors describe a two-stage strategy for resection of a symptomatic 2.3 × 3.3 × 2.7-cm C2 ABC with cord compression in a 13-year-old patient. OBSERVATIONS/METHODS:Initial tumor debulking was completed via a transoral approach, and resection of the involved region spanning the odontoid process to the C2-3 disc space was continued until visualization of the posterior longitudinal ligament. After appropriate decompression was confirmed, the patient was repositioned prone for removal of the residual tumor among the bilateral C2 pedicles. Posterior instrumentation was placed from the occiput to C4, with an autologous rib graft to encourage fusion. The postoperative recovery was uneventful, and 2-month imaging demonstrated postsurgical changes, resolution of compression, and a stable position of the instrumentation and graft material. LESSONS/CONCLUSIONS:The transoral approach facilitates sufficient exposure for the resection of large odontoid ABCs, and posterior stabilization can reduce the risk of postsurgical cervical subluxation. https://thejns.org/doi/10.3171/CASE2485.

The authors present a historical overview of NYU-Bellevue Neurosurgery, highlighting key events and influential faculty. Bellevue Hospital, the first public hospital in the US, was established in 1736 and has grown via its affiliation with New York University (now NYU Langone Health) from 1898 to the present. It maintains a strong commitment to serving disadvantaged populations of New York City and beyond. NYU-Bellevue Neurosurgery began as a department in 1951 under Dr. Thomas Hoen and has since fostered notable faculty and graduates while contributing to the development of clinical neuroscience.

BACKGROUND:Although intracranial arachnoid cysts are often asymptomatic, a small subset of patients develop debilitating symptoms. A cohort of patients with arachnoid cysts with varying presentations underwent endoscopic cystoventriculostomy, with a significant reduction in symptoms. OBSERVATIONS/METHODS:Three patients presented with chronic complaints, all involving headache in addition to other symptoms, and were noted to have large intracranial arachnoid cysts on imaging. Following endoscopic cystoventriculostomy, symptom reduction was both rapid and significant. Postoperative imaging revealed slight changes in cyst size and improvement in mass effect. LESSONS/CONCLUSIONS:Endoscopic cystoventriculostomy for symptomatic arachnoid cysts in adults can decrease the chronic symptoms related to mass effect. Careful planning of the surgical trajectory to target the portion of the arachnoid cyst nearest to the ventricular wall allows for a safe and effective intervention that can lead to significant improvement in symptoms. https://thejns.org/doi/10.3171/CASE24428.

OBJECTIVE:The objective of this study was to report the results of a bibliometric analysis on the modern corpus of literature pertaining to endoscopic third ventriculostomy (ETV). Prior bibliometrics studies on ETV have focused on highly cited articles, but an advanced bibliometric analysis has not yet been conducted. METHODS:The authors queried the Web of Science (WoS) for (ALL = (endoscopic third ventriculostomy)) OR (ALL = (ETV) AND ALL = (neurosurgery)). Articles or reviews published in English were included. Articles, along with their metadata, were exported. Statistical, bibliometric, and network analyses were performed using the Bibliometrix R package and various Python packages. Reference publication year spectroscopy (RPYS), a method that analyzes the frequency with which references are cited in terms of these references' publication years, was employed to explore the historical roots of the field. RESULTS:Between 1994 and 2023, 1663 documents were identified (1382 articles) from 5457 authors. The mean annual growth rate of publications was 4.9%. International coauthorship increased 4-fold over this time period and was noted for 18.95% of published studies from 2011 to 2023. We observed that Child's Nervous System published the most articles, Journal of Neurosurgery (JNS) articles were cited most frequently, and JNS: Pediatrics articles had the highest impact. Female coauthorship increased from < 1% of published studies before 2000 to 19% by 2022, with an increase in female first authorship from 2% in 2005 to 22% in 2022 and at least 1 female coauthor rising from 3% in 2000 to 68% in 2022. Likewise, minority authorship has increased, as in the early ETV literature > 75% of authors were White while currently only 43% are White. The authors of this study also identified the most prolific authors on the subject. Early in the publication record, etiological and technical terms such as "aqueductal stenosis" and "technical note" predominated. More recently, "complications," "failure," "success," "neuroendoscopy," and "choroid plexus cauterization" were prominent. Utilizing RPYS, the authors identified 32 articles that comprise the foundational articles on ETV, published between 1966 and 2010. CONCLUSIONS:Interest in ETV increased in the 1990s with the advent of advanced endoscopic technologies-particularly digital video. The focus of research has shifted from etiology to outcomes, complication management, and technical mastery.