Tumor stiffness and adhesion are decisive factors in neurosurgical strategy, yet they remain absent from standard planning and navigation. Advances in biomechanics allow these properties to be measured and mapped across modalities: magnetic resonance elastography for preoperative stiffness and adhesion, intraoperative ultrasound elastography for real-time updates, and rheometry as biological ground truth. Emerging frameworks could integrate these measurements with artificial intelligence and multimodal neuroimaging to produce probabilistic maps of tumor consistency and brain-tumor interface quality. We define this concept as elasticity-guided neurosurgery: the incorporation of biomechanical parameters into surgical decision-making to improve safety, efficiency, and personalization. By transforming tactile impressions into actionable data, elasticity-guided neurosurgery could represent a paradigm shift toward more information-driven neurosurgical oncology.

Proximal junctional kyphosis (PJK) and failure (PJF) remain challenging and incompletely predictable adverse event following adult spinal deformity (ASD) surgery. Machine learning (ML) models have been proposed to improve risk stratification, but performance varies and clinical applicability remains uncertain. A systematic review and diagnostic test accuracy meta-analysis was performed to synthesize the predictive performance of ML-based models for proximal junctional pathology after ASD surgery. PubMed, Embase, and CENTRAL were searched from inception to February 2026. Studies developing or validating ML models predicting PJK or PJF following ASD surgery were included. Diagnostic performance was synthesized using random-effects models, pooling sensitivity, specificity, diagnostic odds ratio (dOR), and summary receiver operating characteristic (SROC) curves. A prespecified secondary analysis pooled one highest-performing model per study to reduce within-study dependence. Risk of bias was assessed using PROBAST and certainty of evidence using GRADE. Sixteen studies comprising 3625 patients and 30 ML models met inclusion criteria. Twenty-two models provided extractable test-set data for diagnostic synthesis. Pooled sensitivity was 0.51 (95% CI: 0.41-0.61) and specificity 0.84 (95% CI: 0.78-0.89), with a pooled AUC of 0.67 (95% CI: 0.62-0.72). In the highest-performing model analysis, pooled sensitivity improved to 0.63 (95% CI: 0.55-0.71) and AUC to 0.77 95% CI: 0.71- 0.83). Specificity remained high (0.86). External validation was rare, and calibration was inconsistently reported. Frequently prioritized predictors included sagittal alignment parameters, construct characteristics, bone quality metrics, and age. ML-based models demonstrate biologically coherent but clinically moderate discrimination for predicting proximal junctional pathology following ASD surgery. Current performance supports risk stratification rather than categorical decision-making. Progress toward clinically actionable prediction will require standardized endpoint definitions, robust external validation, and calibration-centered reporting.

The National Institutes of Health Stroke Scale (NIHSS) quantifies stroke severity, yet variability in its reporting may reflect healthcare disparities and affect outcomes. This study analyzes trends in NIHSS reporting in the National Inpatient Sample (NIS) database and its relationship with patient characteristics and outcomes. This retrospective cross-sectional study used data from the NIS between May 2016 and December 2022. This nationally representative sample included patients in the US hospitalized with acute ischemic stroke (AIS). Primary outcomes include NIHSS reporting rate over time, factors associated with reporting, and subsequent discharge disposition. Propensity score matching (PSM) accounted for patient demographics, hospital characteristics, severity of illness, and use of reperfusion therapy. Among 4,558,909 AIS hospitalizations, NIHSS was reported in 1,930,880 (42.4%). The proportion of hospitalizations with reported NIHSS increased from 14.33% in December 2016 to 56.27% in December 2022. After PSM, reporting of NIHSS was associated with higher odds of routine discharge (Adjusted Odds Ratio = 1.03, 95% CI: [1.01-1.04]; p < 0.001) and lower odds of inpatient mortality (0.650 [0.632-0.668], p < 0.001). Scores were less likely to be reported in females (0.970 [0.961-0.979], p < 0.001) and Black (0.963 [0.939-0.988], p = 0.004) or Hispanic patients (0.960 [0.926-0.996], p = 0.030), as well as in smaller and less urban hospitals. Since the implementation of NIHSS reporting, rates have increased to more than half of all AIS hospitalizations as of December 2022. NIHSS reporting was significantly associated with improved discharge disposition, and patient demographics impacted odds of having a reported NIHSS, highlighting persistent disparities in stroke care.

The surgical management of pineal cysts (PC) remains controversial, particularly in non-hydrocephalic patients where radiological and clinical correlations are inconsistent. Most studies rely on cyst size or morphology as surgical criteria. This study aims to assess clinical-radiological correlations and outcomes in a consecutive single-center cohort, and to compare outcomes across microsurgical, endoscopic, and stereotactic approaches. A retrospective analysis was performed on 46 symptomatic PC patients treated between 2008 and 2024. Clinical data and radiological data, including cyst dimensions, third ventricle-mesencephalic angle, aqueduct diameter, and predominant expansion were analyzed. Patients were categorized into surgical (n = 18) and non-surgical (n = 28) cohorts. Surgical outcomes were assessed using the Chicago Chiari Outcome Scale (CCOS) at 3-month, 12-month, and long-term follow-up. Statistical comparisons were conducted to correlate radiological markers with symptoms and postoperative outcomes. Headache was the most common symptom in both groups (80%), followed by visual disturbances in the surgical group (33%), and vertigo in the non-surgical group (32%). Compared with the non-surgical cohort, the surgical patients had larger cysts, narrower aqueducts (0.9 vs. 1.6mm, p < 0.001) and a higher prevalence of predominant anterior expansion (67% vs. 7%, p < 0.001). Among all operated patients, 94% achieved good or excellent CCOS outcomes at 12-months, and 93% maintained these outcomes at long-term follow-up (mean 62months, range 16-216months). Neither PC volume nor hydrocephalus predicted consistently postoperative outcome. Microsurgical resection (n = 12) achieved favorable long-term outcome (mean CCOS 14.9), but the highest complication rate (3 patients) and the highest recurrence of headache despite total PC excision. Endoscopic fenestration with ventriculostomy (n = 3) yielded the best long-term outcome (mean CCOS 15.7) with no recurrences. Stereotactic drainage with a catheter with a Rickham reservoir placement (n = 3) provided stable decompression but lower CCOS scores at long-term (mean CCOS 13.0) compared with other approaches. Surgery for symptomatic PC provides durable improvement when guided by radiological-clinical criteria. Aqueduct diameter was more closely associated with outcome than PC size. Microsurgical, endoscopic, and stereotactic approaches each have specific roles that should guide individualized treatment.

Neurosurgical patients frequently require intensive postoperative care. However, data on the factors influencing their outcomes in low-resource environments are limited. This study aimed to identify the predictors of mortality among neurosurgical patients admitted to the Surgical Intensive Care Unit at the Tikur Anbessa Specialized Hospital, Ethiopia. A retrospective cohort study was conducted between January 1, 2024, and January 1, 2025. All neurosurgical patients admitted to the surgical Intensive Care during the study period were reviewed. Patient outcomes were categorized as death during Intensive Care Unit stay or discharge or transfer with clinical improvement. Multivariate logistic regression analysis was performed using SPSS version 27, and variables with p < 0.05 were considered statistically significant. A total of 140 neurosurgical patients were included, with an overall ICU mortality rate of 23% (n = 32). Emergency surgery (AOR = 7.4; 95% CI: 1.26-13.97; p = 0.027), intraoperative blood loss > 1000mL (AOR = 4.0; 95% CI: 1.96-5.29; p = 0.044), lack of continuous postoperative monitoring (AOR = 3.5; 95% CI: 1.93-13.15; p = 0.044), and ICU complications (AOR = 7.8; 95% CI: 1.92-13.49; p = 0.004) were independently associated with increased mortality. 23% Of the neurosurgical patients admitted to the SICU died during the ICU stay. Mortality was independently associated with emergency surgery, significant intraoperative blood loss, lack of continuous postoperative monitoring, and the occurrence of ICU-related complications.

Complete aneurysmal thrombosis is a rare occurrence in which a combination of thrombus and plaque contributes to the complete obliteration of the lumen of an aneurysm, rendering it occult on angiographic imaging. To date, there is a paucity of information in the literature describing the clinical/radiographic presentation and operative management of complete thrombosed aneurysms of the middle cerebral artery. A focused literature review was performed to identify previously reported cases of complete MCA aneurysm thrombosis. Five cases meeting these criteria were identified, of which four underwent open microsurgical management and one was treated endovascularly. We report a clinical case of a 35-year-old female who presented with severe exacerbation of baseline headaches. Radiographic features were suggestive of a ruptured cavernous malformation. In the operating room, a large and completely thrombosed aneurysm of the superior M2 was encountered. The aneurysm was treated with ultrasonic evacuation of the thrombus and plaque, followed by definitive clip reconstruction. Completely thrombosed aneurysms are rare entities that can masquerade cavernous malformations (CCM) and/or intra-axial neoplasms. Following a literature review, we highlight nuances of diagnosis and discuss pearls of surgical management along with the inclusion of a narrated, operative video.

Microvascular procedures demand exceptional precision and are prone to technical errors that compromise outcomes. Performance improves fastest when errors are identified, measured, and corrected early during training. Error-based learning has become an essential part of microsurgical training, highlighting the importance of identifying and learning from mistakes to improve performance. This review aimed to systematically search the literature on all microsurgical errors and categorize them by operative phases. A structured literature search was conducted across Medline, Embase, and Web of Science databases, following PRISMA guidelines. Two reviewers independently screened records and extracted data in duplicate. Articles were included if they evaluated microvascular anastomoses with vessels less than 2 mm in diameter, and if microsurgical errors were detailed along with their impact on outcomes, in particular on anastomotic patency. Given the heterogeneity of the data, a SWiM-style (Synthesis Without Meta-analysis) narrative synthesis was used. A total of 34 studies met the inclusion criteria. Errors were categorized as pre-operative, intra-operative, and post-operative. Intra-operative errors were the most frequently reported. Back-wall stitches, uneven lumens, and excessive suture tension were consistently associated with reduced patency. Several validated scoring tools (e.g., ALI, MARS10, OSATS) were identified as effective in quantifying errors and guiding feedback in training settings. Microvascular anastomosis errors span all phases of the microsurgical procedure and significantly affect anastomotic success. This review offers a structured taxonomy of errors and underscores the importance of error-based learning and assessment in microsurgical training. Standardized error classification may enhance training programs, accelerating the acquisition of microsurgical skills along the learning curve and improving clinical outcomes.

Augmented reality (AR) provides real-time three-dimensional visualization for spinal instrumentation, though its role in spinopelvic stabilization remains limited. While AR-assisted pedicle and S2 alar-iliac screw placement has been reported, AR guidance for a dual-iliac quad-rod construct in spinopelvic dissociation has not. We describe AR-assisted minimally invasive placement of L4-L5 pedicle screws and bilateral iliac screws using intraoperative three-dimensional planning. Fixation was completed without complications and remained stable at last follow-up. This case suggests AR navigation may support accurate and efficient execution of complex minimally invasive spinopelvic fixation.

White matter microdissection represents a valuable method for studying the three-dimensional organization of the human brain. Building on Klingler's classical technique, this approach has regained importance as both a research and educational tool in microneurosurgery. While the white matter dissection of the lateral aspect of the brain has been extensively described, the medial surface has received comparatively less attention. This article represents the second part of a three-paper series on white matter microdissection. It provides a structured, step-by-step demonstration of the dissection of the medial aspect of the brain, with a specific focus on the limbic lobe. As in the first paper, the core content is the supplementary video, which, through editing and annotation, has an enhanced didactic value. The dissection was performed according to the Klingler technique and recorded during the 8th Sulci, Gyri, Ventricles and Fiber Dissection Hands-on Course (Taipei, 2025). The procedure was conducted under microscopic magnification and edited into a didactic video presentation. All identifiable participants provided informed consent for publication. The dissection proceeds through nine main stages, beginning with the identification of the medial sulci and gyri and continuing with the sequential removal of cortical layers and white matter bundles. This systematic approach exposes the cingulum, inferior longitudinal fasciculus, callosal fibers, hippocampal formation, tapetum, thalamic peduncles, and mammillothalamic tract, illustrating the organization of the limbic lobe and the relationships between major white matter tracts and the ventricular walls. This work presents a comprehensive and didactic video demonstration of the medial hemispheric white matter dissection, highlighting the continuity and spatial relationships of limbic and periventricular structures. It contributes to a systematic and anatomically grounded understanding of cerebral white matter organization and supports the educational role of white matter microdissection in neurosurgical anatomy.

A 61-year-old man presented with a non-tapered occlusion at the origin of the left vertebral artery, with the right vertebral artery failing to join the left vertebral artery to form the basilar artery, and basilar artery tip occlusion. Early antegrade endovascular recanalization attempts with microwires failed to traverse the occlusion at the left vertebral artery origin. Digital subtraction angiography revealed a well-developed left ascending cervical artery communicating with the V3 segment of the left vertebral artery. We adopted a retrograde endovascular recanalization strategy and, with adjunctive balloon angioplasty and stent placement, successfully reestablished patency of the left vertebral artery origin.