Citations

BACKGROUND Malignant peripheral nerve sheath tumors (MPNSTs) are malignant tumors that rarely demonstrate heterologous differentiation from angiosarcomatous components. These lesions can be hard to accurately diagnose. OBSERVATIONS A 25-year-old man with neurofibromatosis type 1 and a history of a left lumbar subcutaneous MPNST developed a lung metastasis of only the angiosarcoma component of the MPNST. Prior to H3K27me3 staining of the lung mass, there was no association of the angiosarcoma with the MPNST. Reinterpretation of the lumbar subcutaneous MPNST led to the identification of a previously unrecognized angiosarcomatous portion in that tumor as well. LESSONS This case highlights the importance of using H327me3 staining for accurate diagnosis of biopsies only capturing the heterologous components of MPNST. https://thejns.org/doi/10.3171/CASE251012

BACKGROUND Medication-refractory essential tremor (ET) patients who undergo MR-guided focused ultrasound or Gamma Knife thalamotomy may experience tremor recurrence, prompting rescue deep brain stimulation (DBS). Yet, the impact of prior ventral intermediate nucleus (VIM) lesioning on DBS targeting, microelectrode recording (MER), and stimulation programming remains uncertain. OBSERVATIONS The authors present 3 ET patients undergoing bilateral DBS for tremor recurrence after thalamotomy. Thalamotomy lesions showed depressed electrophysiological activity versus nonlesioned VIM on MER (p = 0.0397) and required smaller DBS charge density increases for tremor control, suggesting irreversible lesion effects despite tremor recurrence. Tremor recurrence correlated with lesion mislocation; specifically, ablations missed the central VIM (mean 1.8 mm) and decussating dentato-rubro-thalamic tract. For rescue DBS, ventral VIM stimulation yields the greatest tremor reduction, while central VIM stimulation balanced tremor control with adverse effects. LESSONS DBS is a safe, effective rescue treatment for failed thalamotomy without needing to retarget the prior lesion site. The authors advocate for prospective studies of initial DBS targeting 2 mm anterior to standard VIM coordinates, reducing intraoperative readjustment for central VIM stimulation; and initial thalamotomy targeting 1 mm anterior and 1.2–1.5 mm superior to standard coordinates for durable tremor control through ablation of both central and ventral VIM. https://thejns.org/doi/10.3171/CASE25955

BACKGROUND Ligamentotaxis-based indirect decompression using lateral approaches is well described for degenerative lumbar disease, yet its application in managing burst fractures remains underexplored. OBSERVATIONS A 72-year-old osteopenic male with an L4 burst fracture underwent a single-position robot-assisted lateral L4 corpectomy, L2–3 oblique lumbar interbody fusion, L5–S1 lateral anterior lumbar interbody fusion, and robot-assisted percutaneous segmental fixation from L2 to the ilium. Postoperative MRI demonstrated significant indirect decompression with a decrease in ligamentous buckling and restoration of the spinal canal cross-sectional area. The ligamentotaxis created by the height and lordosis restoration produced adequate decompression without resection of the ventral retropulsed fragments or posterior direct decompression. LESSONS This case illustrates that single-position lateral lumbar corpectomy can achieve indirect decompression while sparing the morbidity of an open posterior approach. To the authors’ knowledge, this is the first report with MRI evidence of indirect decompression following single-position lateral lumbar corpectomy. https://thejns.org/doi/10.3171/CASE26118

BACKGROUND Cystic adventitial disease (CAD) and intraneural ganglion cysts (IGCs) are rare mucinous lesions typically linked to an articular origin via macroscopic conduits. While secondary propagation between vascular and neural systems may occur through shared fascial sheaths, a direct microvascular route has not been previously described. OBSERVATIONS A 60-year-old man presented with progressive left tibial neuropathy. High-resolution 7T MRI and surgery revealed a large popliteal CAD lesion connecting to the knee joint via the middle genicular artery, alongside a secondary tibial IGC lacking an independent articular nerve connection. Findings demonstrated that high-pressure CAD mucin tracked along a small connecting vascular branch, creating a novel microvascular arterio-neural pathway to infiltrate the tibial nerve. Targeted articular branch disconnection and cyst decompression yielded significant clinical improvement, with no recurrence on 7-month follow-up 7T MRI. LESSONS This case expands the unifying articular theory, demonstrating that synovial fluid propagation can exploit a microvascular arterio-neural pathway rather than strictly macroscopic fascial planes. High-resolution 7T MRI is essential for visualizing these subtle connections. Successful management requires meticulous identification and disconnection of the primary joint connection to prevent recurrence. https://thejns.org/doi/10.3171/CASE26411

Abstract Introduction Intracerebral hemorrhage (ICH) carries higher morbidity and mortality than ischemic stroke. Recent studies have demonstrated improved patient outcomes by applying ultra-early bundled interventions including blood pressure management, coagulopathy reversal, and osmotic therapy. Effective strategies to deliver these ultra-early treatment options are currently being explored. On December 19th, 2022, the Mayo Clinic Comprehensive Stroke Center (CSC) launched the “ICH Phases” communication system to accelerate ICH patient care. Objective To evaluate adherence to the AHA/ASA guidelines in acute ICH care following the implementation of our novel-tiered paging system. Methods We retrospectively reviewed patients admitted with spontaneous ICH during 2024 and 2025. We excluded traumatic cases. We extracted clinical data such as time to imaging, documentation of ICH score, blood pressure control, reversal of anticoagulation, venous thrombo-embolism (VTE) prophylaxis and discharge disposition. Results Among 67 patients, 68.7% underwent CT imaging within 25 minutes. We documented the ICH score within 6 hours in 82.9% of patients. Nearly 94.7% of patients with SBP>140 mm Hg received antihypertensive therapy, yet only 18% reached target BP within 60 minutes. We completed the reversal of anticoagulation within 120 minutes in 75% of patients. VTE prophylaxis was initiated within 24 hours in 91% of patients. Discussion Our novel system demonstrated adherence to the AHA/ASA guidelines, and time sensitive benchmarks in neuroimaging, reversal of anticoagulation, and VTE prophylaxis. Early BP control remains a challenge, that highlights the discrepancy between guidelines and real-ground implementation. Conclusion A novel tiered paging system is effective for enhancing early ICH care. Such a holistic system remains critical for sustained improvement in quality of care.

Abstract Background aneurysmal subarachnoid hemorrhage (aSAH) is neurological emergency associated with substantial mortality and disability. Current grading systems such as the modified Fisher Scale (mFS) and World Federation of Neurological Societies (WFNS) score, rely on semiquantitative and examination based assessments. Hence, they demonstrate limited predictive precision. The enhanced subarachnoid hemorrhage (eSAH) score is a simplified quantitative model integrating age, Glasgow Coma Scale (GCS), and cisternal subarachnoid hemorrhage volume (SAHV) to predict clinical outcomes after aSAH. Methods We performed a retrospective multicenter cohort study that included 1088 patients across three tertiary-care centers the United States. Predictive performance for unfavorable functional outcome, in-hospital mortality and delayed cerebral ischemia (DCI) was evaluated using receiver operating characteristic (ROC) analysis and area under the curve (AUC). Comparative analyses were performed and compared to the WFNS and mFS grading systems. Results the eSAH score demonstrated excellent discrimination for unfavorable functional outcome at discharge ( AUC 0.89 ) and in-hospital mortality (AUC 0.87). The DCI subscore demonstrated good discriminatory performance for predicting DCI (AUC 0.77). Compared with conventional grading systems, this was superior to both the WFNS (AUC 0.75) and the mFS ( AUC 0.70). increasing eSAH scores were additionally associated with progressively higher rates of mortality and unfavorable functional outcomes. Conclusion the eSAH score demonstrates strong external validity, reproducibility and superior predictive performance compared with conventional grading systems in a large multicenter cohort. These findings support the clinical utility of quantitative hemorrhage burden integration for early risk stratification in patients with aSAH.

Abstract Objective Shunt-dependent hydrocephalus is a common and costly complication of aneurysmal subarachnoid hemorrhage (aSAH), affecting up to 28% of survivors. Existing prediction tools, including the Chronic Hydrocephalus Ensuing from SAH Score (CHESS), have limited discriminative accuracy. We developed the CHECKMATE score, a clinically practical tool to improve prediction of ventriculoperitoneal shunt dependency after aSAH. Methods In this multicenter retrospective cohort of 486 patients with aSAH from Mayo Clinic (January 1, 2006-December 31, 2021), we used multivariable logistic regression and machine learning to identify independent predictors of ventriculoperitoneal shunt placement. The CHECKMATE score was derived from 5 weighted variables: symptomatic hydrocephalus (10 points), intraventricular hemorrhage (5 points), SAH volume greater than 10 mL (3 points), neutrophil-to-lymphocyte ratio greater than 12 (2 points), and 10-year incremental age thresholds starting at older than 60 years (1 point each). Results Of 486 patients (mean age, 56.3 years; 64.6% female), 137 (28.2%) required ventriculoperitoneal shunt placement. The CHECKMATE score achieved an area under the curve of 0.808 (compared to 0.737 for CHESS), with a sensitivity of 0.85, specificity of 0.67, and negative predictive value of 0.92 at the optimal cutoff of 14 points. Conclusions The CHECKMATE score outperforms CHESS for predicting ventriculoperitoneal shunt dependency after aSAH and is easily used at the bedside. Its high negative predictive value helps identify low-risk patients who may benefit from earlier external ventricular drain weaning and shorter hospital stays.