Neurosurgery

Radiation-induced intracranial tumors after AVM SRS are extremely rare but long-latency

Among 4376 AVM patients treated with Gamma Knife SRS, 12 developed new intracranial tumors over a median 100-month radiologic follow-up (0.27%). In-field malignant tumors occurred in 0.11% of patients, with a median latency of 13.3 years after SRS. Cumulative in-field tumor incidence was 0.08%, 0.16%, and 0.16% at 10, 15, and 20 years, respectively, suggesting very low but persistent risk. Across 43,950 patient-years, overall annual incidence was 0.027%, increasing from 0.005% within 5 years to 0.046% thereafter. 1

Label-free spectroscopy and mass spectrometry accurately characterize glioma margins intraoperatively

This meta-analysis of 24 studies (1768 patients) evaluated Raman spectroscopy, mass spectrometry, and OCT for intraoperative glioma margin assessment. Pooled sensitivity and specificity across modalities were 0.89 and 0.88, with a diagnostic odds ratio of 65.7, indicating high discriminative performance. Performance remained strong for tumor versus normal brain, infiltrated margin detection, and IDH classification, with modest heterogeneity. Raman spectroscopy and mass spectrometry outperformed OCT, suggesting greater suitability where fine biochemical contrast is critical. 2

Proton therapy for lower-grade glioma offers durable control with modest late toxicity

This single-institution phase II trial enrolled 60 patients with WHO grade 1–2 or IDH-mutant grade 3 gliomas treated with proton therapy. At a median follow-up of 7.0 years, 5-year progression-free and overall survival were 79.1% and 85.6%, respectively. Five-year PFS was highest in IDH-mutant, 1p/19q co-deleted gliomas and lowest in IDH-wildtype tumors, reflecting known biology. New neurocognitive deficits occurred in 26% of patients at 5 years, and neuroendocrine dysfunction in 5.3%, with only one radiation-attributed case. 3

Nester coil MMA embolization matches Onyx outcomes with shorter procedures in chronic subdural hematoma

This multicenter series compared Nester pushable coil versus Onyx MMA embolization for chronic subdural hematoma in 183 patients. After 1:1 propensity matching (67 per group), rates of >50% hematoma reduction were similar for coils versus Onyx (53.7% vs 44.8%). Need for surgical rescue and symptom recurrence did not differ significantly, indicating comparable clinical effectiveness between techniques. Coil embolization had significantly shorter median procedure time than Onyx (34 vs 63 minutes) and less frequent general anesthesia pre-matching. 4