Postoperative remote cerebellar hemorrhage following lumbar laminectomy without cerebrospinal fluid leak: A rare presentation and review of the literature

Here we present a case report detailing an unusual occurrence of Remote Cerebellar Hemorrhage (RCH) post-lumbar laminectomy without the conventional cerebrospinal fluid (CSF) leak. Our patient, a 66-year-old male with neuropathic pain and numbness, underwent a lumbar two to five- laminectomy. Two weeks after the surgery, he developed an intense headache and paresthesia, with neuroimaging revealing superior right cerebellar lesions. Despite comprehensive diagnostic investigations, we found no evidence of typical RCH etiologies such as hypertension, trauma, vascular malformations, or venous sinus thrombosis. This intriguing case not only underscores the need for a multifaceted approach to understanding RCH etiology but also highlights the gaps in our current understanding. Additionally, it contributes to the sparse literature on instances of RCH following lumbar laminectomy in the absence of a CSF leak, thereby emphasizing the importance of continued research into such uncommon occurrences

Clinical course of ventriculoperitoneal shunting for hydrocephalus following glioblastoma surgery: a systematic review and meta-analysis

Surgical resection of glioblastoma (GBM) remains a cornerstone in the current treatment paradigm. The postoperative evolution of hydrocephalus necessitating ventriculoperitoneal shunting (VPS) continues to be defined. Correspondingly the objective of this study was to aggregate pertinent metadata to better define the clinical course of VPS for hydrocephalus following glioblastoma surgery in light of contemporary management. Searches of multiple electronic databases from inception to November 2023 were conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. Outcomes were pooled by random-effects meta-analyses where possible. A total of 12 cohort studies satisfied all selection criteria, describing a total of 6,098 glioblastoma patients after surgery with a total of 261 (4%) of patients requiring postoperative VPS for hydrocephalus. Meta-analysis demonstrated the estimated pooled rate of symptomatic improvement following VPS was 78% (95% CI 66-88), and the estimated pooled rate of VPS revision was 24% (95% CI 16-33). Pooled time from index glioblastoma surgery to VPS surgery was 4.1 months (95% CI 2.8-5.3), and pooled survival time for index VPS surgery was 7.3 months (95% CI 5.4-9.4). Certainty of these outcomes were limited by the heterogenous and palliative nature of postoperative glioblastoma management. Of the limited proportion of glioblastoma patients requiring VPS surgery for hydrocephalus after index surgery, 78% patients are expected to show symptom improvement, and 24% can expect to undergo revision surgery. An individualized approach to each patient is required to optimize both index glioblastoma and VPS surgeries to account for anatomy and goals of care given the poor prognosis of this tumor overall

Characterization of systemic immunosuppression by IDH mutant glioma small extracellular vesicles

Background Gliomas are the most common primary brain tumors and are universally fatal. Mutations in the isocitrate dehydrogenase genes (IDH1 and IDH2) define a distinct glioma subtype associated with an immunosuppressive tumor microenvironment. Mechanisms underlying systemic immunosuppression in IDH mutant (mutIDH) gliomas are largely unknown. Here, we define genotype-specific local and systemic tumor immunomodulatory functions of tumor-derived glioma small extracellular vesicles (TEX). Methods TEX produced by human and murine wildtype and mutant IDH glioma cells (wtIDH and mutIDH, respectively) were isolated by size exclusion chromatography (SEC). TEX morphology, size, quantity, molecular profiles and biodistribution were characterized. TEX were injected into naive and tumor-bearing mice, and the local and systemic immune microenvironment composition was characterized. Results Using in vitro and in vivo glioma models, we show that mutIDH TEX are more numerous, possess distinct morphological features and are more immunosuppressive than wtIDH TEX. mutIDH TEX cargo mimics their parental cells, and induces systemic immune suppression in naive and tumor-bearing mice. TEX derived from mutIDH gliomas and injected into wtIDH tumor-bearing mice reduce tumor-infiltrating effector lymphocytes, dendritic cells and macrophages, and increase circulating monocytes. Astonishingly, mutIDH TEX injected into brain tumor-bearing syngeneic mice accelerate tumor growth and increase mortality compared with wtIDH TEX. Conclusions Targeting of mutIDH TEX represents a novel therapeutic approach in gliomas