Endoscopic Occipital Transtentorial Approach for Dorsal Midbrain Cavernous Malformation: Technical Notes With Illustrative Case.

Background: The dorsal midbrain, an anatomically intricate region, presents significant challenges for traditional surgical interventions due to the heightened risk of vascular and neurological injury, and the necessity of brain tissue retraction.

Methods: This study retrospectively reviewed the case of a 29-year-old male diagnosed with a cavernous malformation located in the dorsal aspect of the left midbrain. The patient underwent resection via the endoscopic occipital transtentorial approach (EOTA) in July 2024. Comprehensive records were analyzed, including preoperative magnetic resonance imaging and computed tomography imaging, detailed surgical notes, and postoperative outcomes.

Results: The patient initially presented with headaches and diplopia. Imaging revealed a 17 × 13 mm tumor in the dorsal aspect of the left midbrain, associated with obstructive hydrocephalus. The 2.5-hour EOTA surgery resulted in complete resection of the tumor, with the resolution of headache symptoms and improvement of diplopia. No new complications were reported postoperatively. The patient was discharged 7 days postsurgery without the need for intensive care unit admission. Pathological examination confirmed the diagnosis of a cavernous malformation. Additionally, the EOTA facilitated a concurrent endoscopic third ventriculostomy, and no evidence of hydrocephalus was observed during the 3-month follow-up period.

Conclusions: The EOTA constitutes a significant advancement in neurosurgical techniques for the resection of dorsal midbrain tumors, enhancing surgical precision and safety. This approach contributes to improved patient outcomes and a reduction in complication rates. Further studies are warranted to validate these findings and to establish standardized protocols for the application of EOTA in midbrain tumor resection.