Cystic vestibular schwannomas often grow more rapidly and adhere more strongly to the facial nerves and brainstem than do solid tumors. Patients with large cystic tumors may experience sudden clinical deterioration during the preoperative waiting period; furthermore, it is important to carefully consider whether to dissect the cyst wall from adjacent structures. Accordingly, we aimed to clarify the influence of different cyst types on surgical strategies. We included 19 patients with large cystic vestibular schwannomas (extrameatal diameter >30 mm) who underwent microsurgical resection. Tumors were classified using the Piccirillo et al. system based on the cyst location and wall thickness. We compared the incidence of sudden clinical deterioration and surgical outcomes according to the cyst types. Peripherally located thin-walled cysts (type B) were significantly more likely to cause sudden clinical deterioration than were centrally located thick-walled cysts (type A). In addition, when the thin cyst wall was firmly adhered to the facial nerve or brainstem, a conservative surgical strategy was applied, with the wall being intentionally left in place rather than attempting forceful dissection. This approach achieved excellent facial nerve preservation but relatively decreased the extent of resection. Taken together, these findings suggest that large cystic vestibular schwannomas with peripherally located thin-walled cysts have a high risk of rapid clinical deterioration and may require early surgical intervention. It is important to adapt the dissection strategy according to cyst wall thickness to achieve optimal postoperative preservation of the facial nerve.

Tarsal tunnel syndrome is an entrapment neuropathy caused by the compression of the tibial nerve and its terminal branches in the tarsal tunnel. Electrophysiological examinations are often used to diagnose tarsal tunnel syndrome. Surgical decompression of the tibial nerve is performed in patients who are resistant to conservative treatment. However, the preoperative electrophysiological findings that predict surgical outcomes remain unknown. This study aimed to clarify the preoperative electrophysiological findings that predict the surgical outcomes of tarsal tunnel syndrome. We reviewed 28 feet of 23 patients who underwent preoperative electrophysiological examinations between November 2021 and October 2024, were diagnosed with tarsal tunnel syndrome, and subsequently underwent surgery. Electrophysiological examinations included nerve conduction study and needle electromyography. We reviewed patient characteristics and electrophysiological findings prior to surgery. Sensory plantar symptoms, such as numbness and pain, were evaluated using the Numerical Rating Scale before and after surgery. Patients were divided into the improvement and non-improvement groups based on the Numerical Rating Scale improvement rate after surgery. A comparative analysis of patient characteristics and preoperative electrophysiological findings was performed between the improvement and non-improvement groups. In a motor nerve conduction study of the tibial nerve, the amplitude of the compound motor action potential evoked by stimulation at the ankle was significantly lower in the non-improvement group than in the improvement group. In tarsal tunnel syndrome, a low compound motor action potential amplitude of the tibial nerve on preoperative motor nerve conduction study may indicate poor symptomatic improvement after surgery. Electrophysiological examinations may be useful for predicting the surgical outcomes of tarsal tunnel syndrome.

Oligodendrogliomas generally have a better prognosis than other adult-type diffuse gliomas. However, although several clinical and radiological prognostic factors have been reported, long-term outcomes remain heterogeneous, and decisions regarding postoperative treatment remain challenging because of concerns about long-term adverse effects. This study aimed to explore prognostic factors by analyzing clinical, radiological, therapeutic, and genetic data from a single-institution cohort.

We retrospectively reviewed adult patients (≥18 years) with isocitrate dehydrogenase-mutant and 1p/19q-codeleted oligodendrogliomas who underwent surgical resection at our institution between 1999 and 2021, with available preoperative magnetic resonance imaging and computed tomography. CDKN2A/B copy number status was assessed using multiplex ligation-dependent probe amplification and confirmed by fluorescence in situ hybridization. Overall survival and progression-free survival were analyzed using the Kaplan-Meier method and Cox proportional hazards models. For overall survival, simple multivariable Cox models adjusted for age and Karnofsky Performance Status were constructed.

A total of 32 patients were included. The median age was 40 years, and the median Karnofsky Performance Status was 90. Calcification and corpus callosum invasion were observed in 46.9% and 40.6% of cases, respectively, and CDKN2A/B hemizygous deletion was identified in four cases. The 5-year progression-free survival was 62.0%, and the 5-year overall survival was 86.5%. On univariable Cox analysis for overall survival, corpus callosum invasion, calcification, and CDKN2A/B hemizygous deletion were significant adverse prognostic factors. In simple multivariable Cox models, CDKN2A/B hemizygous deletion remained associated with shorter overall survival.

Calcification, corpus callosum invasion, and CDKN2A/B hemizygous deletion may be prognostic markers in oligodendroglioma.

This retrospective cohort study evaluated long-term local recurrence rates following microsurgical clipping of anterior circulation unruptured intracranial aneurysms. Between April 2003 and August 2025, 657 patients underwent 700 procedures for 786 aneurysms. Local recurrence was assessed by computed tomography angiography at 5-year intervals. During a mean follow-up of 10.5 ± 3.5 years (6,927.8 patient-years), 9 local recurrences were identified, yielding annual recurrence rates of 0.156% per patient-year and 0.111% per aneurysm-year. Cumulative recurrence-free rates were 100% at 5 years, 99.1% at 10 years, and 98.6% at 15 years. Location-specific analysis revealed significantly higher recurrence rates for internal carotid-anterior choroidal artery aneurysms (0.630% annually) and internal carotid-posterior communicating artery aneurysms (0.262% annually) compared with other locations (p = 0.011). Review of recurrent cases identified 3 mechanistic patterns: closure-line regrowth after parallel clipping (Pattern A, n = 2), residual thin-walled basal footprint in broad-based aneurysms (Pattern B, n = 2), and sub-angiographic remnants preserved for perforator safety (Pattern C, n = 5). The predominance of Pattern C at anterior choroidal artery and posterior communicating artery locations explains the location-specific recurrence risk. All recurrences occurred in aneurysms with complete obliteration (Sindou Grade 0) on early postoperative imaging, whereas no recurrences were observed among 26 cases (3.3%) with small neck remnants (Sindou Grades I-II). Microsurgical clipping of unruptured intracranial aneurysms demonstrated excellent long-term durability with very low local recurrence rates, though the gradual increase beyond 10 years highlights the need for continued surveillance, particularly at locations requiring perforator-preserving techniques.

Endovascular treatment is widely used for intracranial aneurysms, but evidence comparing endovascular treatment with surgical treatment for posterior communicating artery aneurysms is limited. Using a multicenter registry from January 2013 to December 2022, 841 patients with 851 posterior communicating artery aneurysms were analyzed. Logistic regression with multivariable adjustment and inverse probability of treatment weighting was applied to adjust for confounders. Of the aneurysms, 499 (58.6%) were treated by endovascular treatment. Patients undergoing endovascular treatment were generally older, had more comorbidities, and had larger aneurysms than those receiving surgical treatment. Functional outcomes assessed by the modified Rankin Scale showed no significant difference between endovascular treatment and surgical treatment in ruptured aneurysms (poor outcome at discharge: odds ratio, 1.09 [0.74-1.69]; p = 0.698; at final follow-up: odds ratio, 0.74 [0.48-1.15]; p = 0.183), whereas endovascular treatment was associated with significantly better outcomes in unruptured aneurysms (poor outcome at discharge: odds ratio, 0.11 [0.03-0.32]; p < 0.001; at final follow-up: odds ratio, 0.33 [0.11-0.96]; p = 0.045). Intraoperative and postoperative complications were similar overall (interoperative: odds ratio, 0.92 [0.55-1.54]; p = 0.752; postoperative: odds ratio, 0.76 [0.54-1.07]; p = 0.121). Subgroup analyses demonstrated that endovascular treatment reduced intraoperative complications in elderly patients, with a significant interaction between endovascular treatment and elderly age (p = 0.008). Endovascular treatment was associated with markedly higher recurrence (odds ratio, 37.41 [16.63-107.15]; p < 0.001) and retreatment rates (odds ratio, 13.73 [6.32-36.06]; p < 0.001). These findings suggest surgical treatment remains a viable option for ruptured aneurysms, providing similar functional outcomes with lower recurrence and retreatment rates, whereas endovascular treatment is suitable for unruptured aneurysms, offering comparable safety and potential advantages in elderly patients.

Aneurysmal subarachnoid hemorrhage remains a devastating condition with persistently high rates of early mortality and disability. While numerous prognostic models exist, the prognostic relevance of metabolic dysfunction in aneurysmal subarachnoid hemorrhage remains uncertain. We retrospectively analyzed 60 consecutive patients with subarachnoid hemorrhage admitted between 2022 and 2024. Metabolic syndrome and its components-including impaired glucose tolerance, insulin resistance, hypertension, dyslipidemia, and obesity-were evaluated within 24 hours of admission. The primary endpoint was poor functional outcome at discharge (modified Rankin Scale 3-6). Secondary endpoints included in-hospital complications and mortality. In adjusted ridge-penalized logistic regression analyses, impaired glucose tolerance (adjusted odds ratio 4.93, 95% confidence interval 1.39-17.4, p = 0.014) and World Federation of Neurological Surgeons grade ≥3 (adjusted odds ratio 5.12, 95% confidence interval 1.62-16.18, p = 0.006) independently predicted poor outcome. Insulin resistance was independently associated with in-hospital complications (adjusted odds ratio 4.05, 95% confidence interval 1.15-14.3, p = 0.030). Mortality was independently predicted by age (adjusted odds ratio 1.06, 95% confidence interval 1.01-1.12, p = 0.032), World Federation of Neurological Surgeons grade ≥3, and impaired glucose tolerance. The composite metabolic syndrome variable was not an independent predictor of any outcome. In conclusion, specific metabolic abnormalities- impaired glucose tolerance, insulin resistance, and hypertension-rather than metabolic syndrome appear to drive early prognosis after subarachnoid hemorrhage. Early metabolic profiling and individualized glucose control may help identify patients at risk and guide future interventional studies.