Idiopathic normal pressure hydrocephalus (iNPH) is a neurological disease characterized by ventriculomegaly and Hakim's triad. At present, symptoms can be alleviated only by cerebrospinal fluid (CSF) shunt surgery. Yet, various complications after shunting may occur, occasionally requiring repeated shunt revisions. In this retrospective, population-based study, our objective was to compare revision rates and causes for revision surgeries between adjustable shunt valve and fixed-pressure valves in iNPH patients. Altogether 1220 patients were evaluated for possible iNPH at Kuopio University Hospital between 1991 and 2023. Probable iNPH was diagnosed in 809 patients who received their first ventriculoperitoneal shunt (VPS). Of the patient cohort, 566 were shunted using an adjustable valve (2008-2023) and 243 received a fixed pressure valve (1991-2012). Hospital records and nationwide registries were used to construct a timeline for each patient from the shunt insertion and until death (n = 430) or the end of 2023. Overall revision rate was lower in iNPH patients receiving an adjustable valve (14% vs. 30%, p < .001, 95% CI 0.27-0.56). The incidence of multiple revisions was also lower in the adjustable valve group (27% vs. 32% p = 0.002, 95% CI 0.21-0.71). The most common cause for revision was peritoneal catheter malposition in the adjustable valve group (44%) and shunt underdrainage in the fixed-pressure valve group (25%). Adjustable shunt valves have decreased the need for shunt revision surgeries due to under- and overdrainage.

Rosette-forming glioneuronal tumors (RGNT) are rare and novel World Health Organization grade I neoplasms that typically arise in the fourth ventricle and progress slowly. Surgical resection is the standard treatment. However, owing to their adherence to critical structures, complete resection is often not possible. The role of stereotactic radiosurgery (SRS) in the management of RGNT remains inconclusive. We present a case of tissue-confirmed RGNT successfully treated with SRS.A 24-year-old woman presented with diplopia and dysequilibrium and was subsequently diagnosed with a fourth ventricular tumor. Subtotal resection was performed at another hospital, and a tissue-based diagnosis of RGNT was made. After a multidisciplinary discussion and following the patient's willingness, single-session SRS was prescribed at a marginal dose of 12Gy. During the subsequent 66-month follow-up period, radiologic regression of the tumor with corresponding resolution of symptoms was noted. She remained neurologically intact at her last official visit.The treatment paradigm for residual RGNT remains elusive due to its scarcity and varied presentation. We have presented our preliminary experience with a residual RGNT that was managed with SRS, attaining long-term freedom from tumor progression. SRS may be a safe, effective, and durable treatment modality for patients with RGNT.

PURPOSE: Idiopathic normal pressure hydrocephalus (iNPH) is characterised by Hakim's tetrade comprising gait, balance, cognitive and urinary disturbance. As gait deteriorates early, 10-m walking tests (10MWT) before and after lumbar tap or extended lumbar drainage tests have been used to identify patients who may benefit from permanent cerebrospinal fluid diversion in the form of a ventriculoperitoneal (VP) shunt. Whether 10MWT should be performed at fast or normal pace to best predict benefit from shunting has been unclear so far. METHODS: We included 125 iNPH patients into a retrospective, longitudinal, single-centre cohort study and performed 10MWT before and after 72-h lumbar drainage, immediately after VP shunt insertion and at the 6-month, 1-year, 2-year, 3-year, 5-year and 8-year marks postoperatively. RESULTS: We found that time and step count improvements of normal and fast 10MWT before and after lumbar drainage were maintained in the first two to three years postoperatively. Furthermore, fast pace 10MWT time and step count better predicted postoperative gait improvement than normal pace 10MWT. Early responders of fast gait measures (walking pace improved by ≥ 0.1m/s or step count improvement > 10% after lumbar drainage) were 3.91 (pace) and 6.29 (steps) times more likely to benefit from surgery as opposed to 2.64 (pace) and 1.93 (steps) times for normal walking pace. CONCLUSIONS : Our study suggests that the 10MWT should be performed at fast pace (maximum speed), and when normal and fast pace results are contradictory, the fast pace outcome should take priority.

Unilateral biportal endoscopy (UBE) has expanded as a minimally invasive option for spinal decompression, but complication profiles and their optimal management remain inconsistently reported. This review aimed to synthesize evidence on the incidence, prevention, and management of UBE-related complications and to propose practical management algorithms. A PRISMA-aligned search of PubMed, Scopus, Web of Science, and Ovid identified studies (2020-2025) reporting perioperative complications in UBE. Primary inclusion criteria were biportal endoscopic spinal procedures with ≥ 50 patients and extractable complication data; secondary reviews were included for contextual synthesis. Levels of evidence (Oxford CEBM) and risk of bias (Newcastle-Ottawa Scale) were assessed for primary cohorts. Crude pooled incidences were calculated from primary cohorts only; secondary literature was analyzed qualitatively. Eighteen studies met inclusion criteria: eight primary UBE cohorts (3,433 lumbar cases) and ten secondary reviews. Across nine lumbar cohorts, crude pooled incidences were 2.4% for dural tear, about 2% for symptomatic epidural hematoma and lesion recurrence, 2.5% for incomplete decompression, 0.09% for surgical site infection, and 1.4% for reoperation, with higher rates early in the learning curve. Cervical and thoracic applications were sparsely reported and not suitable for pooled analysis. Algorithms were constructed for dural tear, epidural hematoma, incomplete decompression, and neural complications. Lumbar UBE decompression appears safe and reproducible in experienced hands when standardized technical strategies are applied, but the evidence base is limited by retrospective design, heterogeneity, and concentration in high-volume centers. The proposed algorithms should be regarded as evidence-informed guidance requiring prospective validation in multicenter cohorts.

In Neurosurgery, stereotactic biopsy represents the main minimally invasive surgical technique to target deep and hard-to-reach brain sites that are not accessible by traditional surgical methods. The best trajectory for biopsy needle insertion is planned on the basis of CT or MRI studies. According to the relevant literature, although biopsy of the posterior cranial fossa with Leksell® Vantage™ Head Frame is possible, it involves several technical and clinical challenges. We describe an alternative configuration of the Leksell® Vantage™ system that addresses these limitations in the management of posterior cranial fossa lesions. At our Department (IRCCS Ospedale Policlinico San Martino in Genoa) we have used Leksell® Vantage™ stereotactic system together with Medtronic StealthStation™ S8 planning software to perform a series of seven stereotactic biopsies in the occipital or cerebellar region by rotating the stereotactic helmet 180° on the axial plane, resulting in an inversion of both the anteroposterior and lateral-lateral axes. We demonstrate that stereotactic posterior fossa biopsies can be performed with helmet rotation, without additional procedural complications. No similar approach has previously been described in the literature. This approach significantly enhances access to the posterior cranial fossa and occipital lesions. This optimisation improves manoeuvrability, provides a more advantageous viewing angle for the needle-biopsy trajectory and allows for a less complex preoperative planning. The approach remains minimally invasive and is generally compatible with execution under conscious sedation.

Intraoperative assessment of aneurysm clipping remains technically challenging, particularly in identifying misclippings, aneurysmal remnants, and vessel compromise. Indocyanine green videoangiography (ICG-VA) provides real-time visualization but lacks hemodynamic quantification. FLOW 800 is a semi quantitative analysis tool that enhances blood flow evaluation. This meta-analysis aims to evaluate the combined diagnostic efficacy of ICG-VA and FLOW 800 in intracranial aneurysm surgery, focusing on intraoperative outcomes. A systematic review was conducted in five databases (PubMed, Embase, Scopus, Web of Science, CENTRAL). The protocol was registered in PROSPERO (CRD420251014600). Twelve studies were included in the qualitative synthesis (344 aneurysms), of which eight contributed quantitative data to the meta-analysis (277 aneurysms). Pooled proportions of misclipping, aneurysmal remnant, vascular stenosis/occlusion, and clip repositioning were calculated using a random-effects model. Subgroup analyses, meta-regression, leave-one-out sensitivity analysis, and assessment of publication bias (funnel plot) were performed. Risk of bias was assessed using the QUADAS-2 tool. The pooled intraoperative detection rates using ICG-VA and FLOW 800 were: misclipping 9.36% (95% CI: 4.75-17.64), aneurysm remnant 6.55% (95% CI: 3.29-12.65), vessel stenosis or occlusion 6.90% (95% CI: 3.28-13.96), and clip repositioning 8.13% (95% CI: 4.05-15.63). Retrospective studies showed higher detection rates than prospective ones. Meta-regression identified study design as a significant predictor for all outcomes (p < 0.0001), while older patient age was associated with increased remnant detection (p = 0.0247) and clip repositioning (p = 0.0073). Funnel plots revealed slight asymmetry, and GRADE evaluation indicated moderate certainty for misclipping and clip repositioning, and low certainty for remnants and stenosis. The combined use of ICG-VA and FLOW 800 enhances the intraoperative detection of misclipping, residual aneurysm, and flow disturbances not evident with ICG-VA alone. These findings support its role as a complementary intraoperative tool. However, due to limited validation against angiographic standards, it should not replace DSA. Further prospective studies are warranted to confirm its clinical utility and encourage broader adoption in neurosurgical practice.

Cavernous sinus dural arteriovenous fistula (CS-DAVF) is a rare vascular disorder, with clinical manifestations largely determined by venous drainage patterns. Conventional endovascular treatment via the inferior petrosal sinus or superior ophthalmic vein may be unsuccessful when these access routes are occluded. We report a case of an CS-DAVF (Barrow type D) in which two prior endovascular attempts failed, and complete obliteration of the fistula was subsequently achieved through direct puncture of the cavernous sinus under endoscopic endonasal guidance. Postoperatively, the patient experienced complete resolution of pulsatile tinnitus and stabilization of ocular function. This case suggests that the endoscopic endonasal approach may represent a safe and effective alternative for carefully selected indirect CS-DAVF patients when standard endovascular access is not feasible.

Contusion expansion is a key determinant of outcome after traumatic brain injury (TBI). Because many patients develop acute coagulopathy, it has been proposed that hemostatic changes may drive this expansion, but the link remains uncertain. In this retrospective single-center cohort, we included adults with isolated moderate-to-severe TBI and no pre-injury antithrombotic therapy. The hemostatic markers activated partial thromboplastin time (APTT), prothrombin time (PT, reported as INR), platelet count (PLT), and fibrinogen were measured on admission and during the first 72h. Contusion volumes were derived from serial CT scans. Associations between hemostatic markers and contusion volumes over time were analyzed using generalized additive mixed models (GAMMs), adjusting for confounders. Among 109 patients, median admission values were fibrinogen 2.4g/L, PT-INR 1.0, APTT 29s, and PLT 233 × 109/L. After admission, fibrinogen and PLT declined, whereas PT-INR and APTT increased modestly. Contusion volume increased from a median of 0.7ml at baseline to 4.6ml on the third CT. In univariable models, higher APTT and PT-INR values and lower platelet counts were associated with larger contusion volumes, but these associations lost significance after adjustment for age and time from injury. Hemostatic disturbances, as measured by standard coagulation assays, were common after TBI but not independently associated with contusion volume over time.

BackgroundEndovascular therapy (EVT) is the standard of care for acute ischemic stroke due to large vessel occlusion. While predictors of 90-day functional outcome are well-established, the determinants of functional recovery remain less clearly defined in the post-discharge period for patients with initial disability. We aimed to identify the predictors of functional outcome at 3 months in patients who underwent EVT and were discharged with an unmet need for recovery (modified Rankin scale (mRS) score > 2).MethodsA multi-center, observational cohort study was conducted using data from the Big Data Observatory Platform for Stroke in China. We included 836 patients from eight comprehensive stroke centers (August 2018 – December 2024) who received EVT, had a pre-stroke mRS of 0–2, and had an mRS > 2 at discharge. The primary outcome was functional outcome at 3 months post-EVT, defined as an mRS score of 0–2. Univariate and multivariate logistic regression analyses were performed to identify independent predictors.ResultsOf the 836 patients, 151 (18.1%) achieved a favorable functional outcome (mRS 0–2) at 3 months. In univariate analysis, the favorable outcome group was significantly younger, had a lower pre-EVT NIHSS, a lower rate of atrial fibrillation, a higher rate of intravenous thrombolysis, a higher rate of complete recanalization (mTICI 3), and a lower rate of parenchymal hematoma (PH) (all p < 0.05). Multivariate regression confirmed four independent predictors: younger age (aOR: 0.973; 95% CI: 0.958–0.989; p = 0.001), lower pre-EVT NIHSS (aOR: 0.940; 95% CI: 0.912–0.968; p < 0.001), complete recanalization (aOR: 1.921; 95% CI: 1.305–2.826; p = 0.001), and absence of PH (aOR: 0.424; 95% CI: 0.235–0.768; p = 0.005).ConclusionA significant proportion of patients discharged with disability experiences meaningful functional recovery by 3 months post-EVT. The key predictors of this subsequent recovery are younger age, milder initial stroke severity, complete reperfusion, and the avoidance of hemorrhagic complications.

BackgroundCranioplasty restores cranial integrity following decompressive craniectomy or skull trauma. Despite its reconstructive benefits, post-cranioplasty complication rates are high. Post-operative drainage has been proposed to mitigate these risks, yet its effectiveness remains uncertain. This study evaluates the impact of post-cranioplasty drain insertion on surgical outcomes.MethodsA systematic literature search of MEDLINE, Embase, and Cochrane CENTRAL Library was conducted in accordance with PRISMA guidelines (PROSPEROID:CRD420251030365). Studies reporting cranioplasty outcomes with post-operative drainage were selected. Primary outcomes were complication rates, including infection, haemorrhage, and cerebrospinal fluid (CSF) leak.ResultsFour studies met the inclusion criteria, comprising 522 patients (mean age 43.7 years) who underwent cranioplasty—282 with post-operative drainage and 240 without. Following decompressive craniectomy, the most common indications for cranioplasty were traumatic brain injury (196/514, 38.1%), vascular causes (187/514, 36.4%), and infection (25/514, 4.9%). All studies reported subgaleal drain use, with one study (25%) using epidural drains in an unspecified number of patients. The overall post-operative complication rate was 75/522 (14.4%), occurring in 23/282 drained patients (8.2%) and 52/240 (21.7%) undrained patients. A meta-analysis comparing post-operative complication rates across all studies between patients with and without post-cranioplasty drainage yielded a pooled risk ratio (RR) of 0.51 (95% CI: 0.21–1.24, p = 0.095).ConclusionsThe results suggest post-cranioplasty drainage does not significantly alter complication rates. However, heterogeneity in drainage protocols limits attribution of outcomes to specific modalities. Going forward, moderated prospective trials are needed to establish standardised post-cranioplasty drainage protocols.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00701-025-06766-3.