Sahin Hanalioglu

Introduction: Patient and arteriovenous malformation (AVM) characteristics that portend success after treatment for low-grade brain AVMs remain unknown. Patients and methods: We utilised the MISTA multicentre registry to identify patients with Spetzler–Martin (SM) grade I or II AVMs treated with stand-alone curative-intent intervention (resection, stereotactic radiosurgery [SRS] or endovascular embolisation). Bivariate and multivariable analyses were performed to identify patient and AVM characteristics predictive of complete obliteration or favourable outcome (complete obliteration without new permanent deficit or post-treatment haemorrhage). Results: A total of 522 patients were included (292 microsurgery, 152 SRS, 78 embolisation). Complete obliteration rates differed between microsurgery (95.9%), SRS (75.0%) and embolisation (71.8%) (P < .001); among patients classified as cured, digital subtraction angiography (DSA) confirmed obliteration in 96.1%, 75.9% and 52.4%, respectively. Favourable outcome was achieved in 89.4%, 64.5% and 67.9% (P < .001). In adjusted models for obliteration, elderly age (odds ratio [OR] 0.49, P = .022), larger nidus (OR 0.64, P = .005) and compacted morphology (OR 1.93, P = .019) were independent predictors overall; paediatric age predicted incomplete obliteration after microsurgery (OR 0.05, P = .045), and elderly age (OR 0.19, P = .001) and larger nidus (OR 0.59, P = .015) after SRS. For favourable outcome, SM grade II overall (adjusted OR [aOR] 0.58, P = .031) and elderly age after SRS (aOR 0.31, P = .019) were independent negative predictors. Discussion: Low-grade AVMs showed high rates of complete obliteration, though DSA-confirmed rates were substantially lower after embolisation, underscoring the importance of angiographic confirmation. Conclusion: The predictors identified in this study may help guide management when 2 or 3 of the primary treatment options carry clinical equipoise.

Background: Psychiatric inpatients may be vulnerable to head trauma; however, associations among psychiatric diagnosis, trauma mechanisms, and acute trauma-related neuroimaging findings among patients requiring neurosurgical consultation remain unclear. Methods: This retrospective observational study included psychiatric inpatients referred for neurosurgical consultation after head trauma at a tertiary neuropsychiatric specialty hospital between July 2022 and December 2025. Psychiatric diagnoses were grouped into psychotic, mood, substance use, organic/symptomatic, and other disorders. Trauma mechanisms were classified as falls, self-harm, assault/fight-related injuries, and other trauma types. Radiological findings were classified as trauma-related abnormalities or secondary incidental findings, including age-related changes. Associations were evaluated using chi-square tests, with false discovery rate correction applied to global and binary comparisons. Exploratory multivariable regression models were used as sensitivity analyses. Results: The cohort comprised 461 psychiatric inpatients who sustained head trauma, underwent radiological imaging, and were referred for neurosurgical consultation. Trauma mechanisms differed significantly across psychiatric diagnostic groups (χ² = 30.89, p = 0.002). Falls were the most common mechanism (189/461, 41.0%). Assault/fight-related trauma showed the clearest diagnosis-associated pattern (χ² = 19.72, p < 0.001, Cramér’s V = 0.207) and remained the only significant binary outcome after false discovery rate correction. Acute trauma-related imaging findings were observed in 35 patients (7.6%) and were not associated with psychiatric diagnosis (χ² = 6.16, p = 0.187). Calcifications were the most frequent imaging finding (191/461, 41.4%). Conclusions: In psychiatric inpatients, while head trauma patterns and neuroimaging findings have the potential to be explained by psychiatric diagnoses, they may also reflect unmeasured behavioral and clinical factors.

Background: Hemifacial spasm (HFS) is most commonly caused by arterial compression at the root exit zone (REZ) of the facial nerve. In contrast, isolated venous compression in the absence of arterial involvement is uncommon, accounting for 0.4–5.5% of cases in surgical series, and poses diagnostic challenges due to the subtle appearance of venous structures on conventional neuroimaging. This rarity highlights the importance of recognizing pure venous neurovascular conflict as a distinct, albeit underdiagnosed, and etiology of HFS. Case Description: We report a 69-year-old woman with a 5-year history of refractory right-sided HFS. Although preoperative magnetic resonance imaging suggested possible arterial contact, retrosigmoid exploration revealed compression of the facial nerve REZ by a transverse pontine vein coursing along the middle cerebellar peduncle, with no arterial offender identified. Microvascular decompression was performed through careful mobilization and transposition of the offending vein using Teflon interposition. Intraoperative quantitative lateral spread response (LSR) monitoring showed marked attenuation of response amplitudes following decompression. The patient experienced immediate and complete resolution of symptoms postoperatively. Conclusion: This case illustrates that pure venous compression by a transverse pontine vein is a rare but surgically treatable cause of HFS that can be misinterpreted as arterial conflict on imaging. A successful outcome was achieved through meticulous intraoperative identification and vein-preserving decompression, combined with quantitative LSR monitoring, which proved valuable even without complete response disappearance. Thorough exposure of the REZ, including endoscopic inspection when indicated, remains important to identify such atypical neurovascular conflicts.

Background/Objectives: A1 segment asymmetry, including hypoplasia and aplasia, is a well-recognized anatomical variation associated with altered hemodynamic stress and anterior communicating artery (ACoA) aneurysm formation. However, its influence on subsequent aneurysm rupture risk remains controversial. This study aimed to evaluate the relationship between A1 segment morphology and aneurysm rupture risk, as well as its association with aneurysm size and morphological complexity. Methods: A retrospective single-institution analysis was conducted on 211 patients treated for ACoA aneurysms between June 2016 and March 2025. A1 segment morphology was assessed using digital subtraction angiography and categorized as symmetric, hypoplastic (diameter < 1 mm or p = 0.251) or mean aneurysm diameter (p = 0.996). Univariate analysis demonstrated that younger age (p = 0.006), male sex (p = 0.016), and smoking (p = 0.033) were associated with rupture. However, none of these factors, including A1 morphology, remained independent predictors of rupture in the multivariable logistic regression model. Conclusions: Although A1 segment asymmetry is common in patients with ACoA aneurysms, it does not independently influence rupture risk or aneurysm morphology. Our findings suggest that rupture behavior is driven primarily by dynamic hemodynamic factors rather than static anatomical variations.

Background: Glioblastoma (GBM) is a highly aggressive primary brain tumor that can integrate into neural circuits implicated in tumor progression and treatment resistance. Gabapentinoids are proposed to disrupt such interactions. We analyzed postoperative gabapentinoid use and overall survival (OS) in nationwide adult GBM cohort. Methods: This retrospective population-based study utilized the Turkish national healthcare registry, identifying adult patients with pathology-confirmed GBM who underwent surgery between 2016 and 2024. The primary endpoint was OS. Stabilized inverse probability of treatment weighting (sIPTW) was applied to adjust for potential confounders, and survival associations were evaluated using multivariable Cox proportional hazards models. Survival curves were analyzed using Kaplan-Meier estimator, and statistical significance was defined as a two-sided P-value <.05. Results: Of 11,924 patients, 701 (5.9%) utilized postoperative gabapentinoids. In sIPTW-weighted analyses, gabapentinoid utilization was associated with reduced mortality risk (HR 0.75; 95% CI, 0.66-0.84; P < .001). Age-stratified analyses demonstrated effect modification, with survival benefit observed in patients aged ≥55 years (HR 0.70; 95% CI, 0.60-0.81) but not in those 400 mg/day). Conclusions: In this nationwide cohort, postoperative gabapentinoid use was associated with improved survival in patients with GBM, particularly aged ≥55 years. These findings support targeting neuron-glioma axis and warrant prospective evaluation of gabapentinoids as adjuvant therapies in GBM.

Background: Ischemic complications remain a significant risk indicator of morbidity after meningioma surgery. While tumor size and extent of resection (EOR) are recognized risk factors, the prognostic impact of peritumoral brain edema volume (PTBEV) is not fully established. This study investigated whether preoperative tumor volume (TV) and PTBEV independently predict postoperative ischemia and neurological morbidity. Methods: We retrospectively investigated 152 patients who underwent resection of intracranial meningiomas from 2008 to 2023. Preoperative post-contrast T1W and Fluid-Attenuated Inversion Recovery (FLAIR) MRI were used to quantify TV and PTBEV, and postoperative DWI within 72 hours post-surgery was used to identify ischemic lesions. Volumetric segmentation was performed in 3D Slicer™ and validated by five independent reviewers. Statistical analysis included Spearman’s correlation, univariate and multivariate linear regression for predictors of postoperative ischemic volume (PIV), and binary logistic regression for new neurological deficits. The P value < .05 was considered significant. Results: Median preoperative TV was 23.1 cm³ (IQR 9.3-48.4 cm³), and PTBEV was 3.5 cm³ (IQR 0.0-28.4 cm³). Median PIV was 1.5 cm³ (IQR 0.0-5.3). PIV correlated with preoperative TV (r = 0.393, P < .001) and PTBEV (r = 0.446, P < .001). Multivariate regression identified preoperative PTBEV (P < .001), preoperative TV (P = .015), and subtotal resection (STR) vs. GTR (P = .033) as independent predictors of postoperative ischemia. Overall, 11.8% of the patients developed new neurological deficits (1.3% permanent). Ischemic volumes >2 cm³ significantly increased risk of new neurological non-cranial nerve deficits (OR = 6.667, 95% CI 1.408-31.556, P = .017). Conclusion: Preoperative tumor and edema volumes are independent predictors of postoperative ischemia. Even modest ischemic lesions (>2 cm³) can cause clinically relevant morbidity. Volumetric biomarkers should be integrated into surgical planning, with prospective multicenter validation warranted.

This review article delves into the significant role of three-dimensional (3D) digital modeling technologies in neurosurgical training, planning, and intraoperative guidance. With the increasing complexity and individuality of neurosurgical procedures, 3D modeling emerges as a transformative tool, providing neurosurgeons with immersive, patient-specific simulations to enhance anatomical understanding and procedural accuracy. The article examines the latest developments in augmented reality (AR) and virtual reality (VR). It discusses their applications in creating interactive surgical environments that bridge the gap between theoretical knowledge and practical skills. It emphasizes the impact of digital 3D models on neuroanatomical education and how they facilitate the visualization of intricate spatial relationships, significantly contributing to surgical precision and patient safety. Furthermore, the review explores the practicality, accessibility, and future prospects of these technologies, highlighting the need for continuous research and interdisciplinary collaboration to overcome current limitations and fully harness their potential for neurosurgical excellence.

Stereotactic radiosurgery was associated with a higher obliteration rate compared with embolization in patients with eloquent brain arteriovenous malformations, whereas there was no evidence of a difference in functional outcomes or complications after adjustment.