早川 基治

BACKGROUND: Although transcervical styloidectomy is an established treatment for Eagle syndrome, the narrow operative corridor can make deep exposure challenging, particularly in patients at higher risk of complications. We report two cases in which neurosurgical microsurgical techniques provided wider and clearer deep visualization than conventional methods. METHODS: Two patients underwent transcervical styloidectomy using microsurgical techniques commonly employed in neurosurgery: one with Eagle syndrome-related internal carotid artery dissection on antiplatelet therapy, and the other with glossopharyngeal neuralgia and a short neck requiring improved deep exposure. RESULTS: The use of microsurgical techniques provided a wider operative corridor to the deep surgical field than the conventional approach, enabled reliable hemostasis and atraumatic dissection. Both patients achieved satisfactory clinical improvement without postoperative complications. CONCLUSIONS: Styloidectomy using microsurgical technique can provide wider operative exposure than conventional techniques, and its use should be considered particularly in patients at higher risk of complications.

Posterior Quadrant Disconnection is a surgical technique designed to suppress seizure propagation while preserving motor and sensory functions in patients with drug-resistant epilepsy. Although seizure outcomes following this procedure have been reported, detailed evaluations of its impact on higher cognitive functions remain limited. This study aimed to assess the long-term seizure and cognitive outcomes following PQD in the non-dominant hemisphere, thereby evaluating the efficacy and safety of the procedure. In this case, the patient with drug-resistant epilepsy underwent preoperative evaluation using stereo electroencephalography (SEEG) to identify seizure onset zones and functional mapping related to visuospatial cognition. Following this assessment, PQD was performed. Postoperative outcomes were monitored over a 2-years period, focusing on seizure control and higher cognitive function. The patient achieved Engel class I status postoperatively, indicating complete seizure cessation. While transient hemispatial neglect was observed immediately after surgery, gradual improvement was noted over time. Furthermore, visual memory and cognitive functions showed a tendency to improve, and there were no significant declines in facial recognition or scene recognition abilities. These findings suggest that PQD can effectively improve seizure outcomes while minimizing long-term impacts on cognitive functions. This case highlights the potential of PQD to offer substantial seizure control with limited permanent effects on higher cognitive functions. By providing valuable insights into the safety and efficacy of PQD in the non-dominant hemisphere, this study underscores its viability as a treatment option for selected cases of drug-resistant epilepsy.

OBJECTIVE: Knowledge of the location of tumor-feeding arteries is necessary for the safe surgery of intracranial meningiomas. Hence, this retrospective study aimed to comprehensively analyze the distribution of tumor-feeding arteries. METHODS: Patients who underwent intracranial meningioma surgery at our institution between 2015 and 2023 were included in this study. The tumor attachment sites and tumor-feeding arteries were evaluated based on the results of preoperative examinations. The tumor attachment sites were classified as non-skull bases (convexity, parasagittal, and falx) or skull bases (anterior skull base, sphenoid ridge, sphenopetroclival, petrous, tentorial, cerebellar convexity, and foramen magnum). These tumors were further subdivided according to their attachment areas. RESULTS: Among the 180 patients included, the tumor-feeding arteries were identified in 177 patients (98.3%). In 67 patients with non-skull base meningiomas, the middle meningeal artery primarily functioned as a tumor-feeding artery in the anterior and middle regions (78 of 108 feeding arteries, 72.2%), while the extracranial artery served as a tumor-feeding artery in the posterior region (20 of 37 feeding arteries, 54.1%). Conversely, skull base meningiomas exhibited a higher frequency of having tumor-feeding arteries derived from the internal carotid artery (132 of 278 feeding arteries; 47.5%); these tumor-feeding arteries are often found at the deepest part of the surgical field during tumor resection and require careful intraoperative handling. CONCLUSIONS: Tumor-feeding arteries originate from different dural arteries depending on the tumor attachment site. These findings could help enhance surgical safety, especially in patients with meningiomas who have not undergone preoperative angiography.