國井 尚人

OBJECTIVE: Patients with temporal lobe epilepsy (TLE) suffer from epileptic seizures and memory decline. While focal resection eliminates seizures in 60-70% of patients, surgery carries the risk of further compromising memory. We hypothesized that hippocampal neurofeedback (NF) will induce targeted brain activity associated with memory function. METHODS: Patients with intracranial electrodes implanted in bilateral hippocampi performed a memory NF task, developed specifically for this project. The NF task involved real-time analysis of hippocampal activity using the electrode in the less-affected hippocampus while conducting a memory task. Changes in theta activity and task performance were assessed. RESULTS: The NF task was conducted in seven TLE patients. In five patients, theta activity increased significantly in the targeted hippocampus (Mann-Kendall test; p < 0.05). Mixed linear model analysis across all sessions revealed a significant increase in theta activity in the targeted hippocampus (p = 0.0032), with no significant change contralaterally (p = 0.19). Three additional TLE patients underwent random NF to assess if theta activity was induced merely by the encoding process, but none of them showed significant changes in theta activity. CONCLUSION: Memory NF task effectively induced targeted hippocampal activity in TLE patients. SIGNIFICANCE: Hippocampal NF may enhance memory function in TLE patients prior to focal resection.

BACKGROUND: The incidence of cerebral aneurysms in polyarteritis nodosa (PN) is low, and reports of subarachnoid hemorrhage (SAH) in patients with PN are even rarer. The necessity of head imaging may be underestimated, particularly when the patient is in remission. OBSERVATIONS: A 20-year-old female with PN, who had been in remission following anti-interleukin-6 receptor antibody therapy, developed SAH and was admitted to the authors' department. Cerebral angiography revealed multiple beaded changes in both carotid and vertebral arterial systems, along with several small aneurysms. These findings posed substantial difficulty in identifying the bleeding source and proceeding with surgical intervention. Therefore, the authors intensified the immunosuppressive therapy targeting the underlying PN. The patient remained free from rebleeding, her headaches and other symptoms resolved, and she was discharged in ambulatory condition. Follow-up MR angiography 3 months after discharge confirmed resolution of the small aneurysms. LESSONS: This case suggests that enhanced immunosuppressive therapy may be effective in treating both extracranial and intracranial vascular lesions in PN. In patients with PN, early and serial head imaging may be beneficial. The appearance of de novo aneurysms in the context of disease progression may indicate the need for more aggressive treatment. https://thejns.org/doi/10.3171/CASE25617.

BACKGROUND: Redo awake surgery is ideal for recurrent malignant gliomas in the language-dominant hemisphere, but it may not always be optimal because of inadequate awake mapping. In this report, the authors describe a case of recurrent language-dominant frontal glioma in which a super-selective Wada (ssWada) test and super-selective cone-beam CT angiography (ssCBCTA) enabled successful tumor removal under general anesthesia after awake surgery. OBSERVATIONS: A woman in her 30s underwent awake surgery for left frontal glioma recurrence 2 years after the initial resection. Three years after another recurrence, the ssWada test and ssCBCTA revealed that the tumor-supplying artery did not perfuse the functional cortex, allowing safe and maximal resection under general anesthesia. Postoperatively, she had mild motor aphasia but recovered quickly with minimal sequelae. LESSONS: The combined use of the ssWada test and ssCBCTA enables precise preoperative language mapping and safe tumor resection. Originally developed for epilepsy surgery, the ssWada test is valuable for functional mapping and, when paired with ssCBCTA, provides a 3D understanding of the lesions. This combination serves as a critical preoperative tool for tumors in the language-dominant hemisphere. https://thejns.org/doi/10.3171/CASE25384.

Somatic PIK3CA and MAP3K3 mutations in cerebral and spinal cavernous malformations (CMs) have been identified in recent studies. However, their significance in the clinical presentation and risk of hemorrhage in CMs remains poorly understood. We aimed to analyze the association between these mutations and the clinical characteristics of CMs. Among patients with CMs who underwent surgical resection of lesions between July 2002 and March 2022, those with complete clinical and radiological data at the time of initial surgery were included. Somatic PIK3CA and MAP3K3 mutations were detected using droplet digital polymerase chain reaction. Subsequently, the clinical and radiological characteristics correlated with these mutations were assessed. Furthermore, the effect of these mutations on the first symptomatic intraparenchymal hemorrhage during follow-up was evaluated. In total, 72 patients were included; among them, 50 had sufficient mutation data. PIK3CA E542K, E545K, and H1047R mutations were identified in 7 (14%), 7 (14%), and 15 (30%) patients, respectively. MAP3K3 I441M was identified in 10 (20%) patients (8 [16%] had both PIK3CA and MAP3K3 mutations). MAP3K3 I441M was more common in patients with Zabramski classification type II lesions than in those with CMs of other types (p = 0.024). Multivariate Cox regression analyses identified the presence of a PIK3CA mutation as a risk factor for early (re)hemorrhage. The results suggest that PIK3CA and MAP3K3 mutations are associated with clinical and radiological characteristics in patients with CMs and that the presence of a somatic PIK3CA mutation increases susceptibility to hemorrhage. These findings may help guide future therapeutic strategies.

BACKGROUND: Gait-induced seizures are a rare manifestation of reflex epilepsy. Pathophysiology of this phenomenon has not been fully understood. CASE PRESENTATION: A 28-year-old woman presented with a long history of "falls" following paroxysmal bilateral leg stiffness triggered by walking. Scalp electroencephalogram (EEG) revealed low-amplitude rhythmic beta activity, maximal at the Cz electrode, during these events. Magnetoencephalography demonstrated repetitive sharp waves source-localized to the right primary motor cortex. Multiple anti-seizure medications failed to improve her symptoms; however, the clinical manifestation was consistent with epilepsy with gait-induced seizures. Intracranial subdural EEG recording was performed and confirmed ictal activity originating from the right supplementary motor area. Resection of this area resulted in complete resolution of her symptoms. DISCUSSION: This is the first reported case of successful resective surgery for epilepsy with gait-induced seizure. Brain networks involving cortical regions responsible for the initiation or execution of walking presumably played a key role in the generation of gait-induced seizures. Careful assessment using non-invasive neurophysiological studies facilitated accurate diagnosis, successful intracranial recordings, and effective resective surgery.