Microsurgical anatomy of the foramen of Luschka in the cerebellopontine angle, and its vascular supply.

Cerebellopontine angle and vascular supply of adjacent brainstem and cerebellum are susceptible to compression and eventual damage by tumors. Delicate and complicated neurosurgical operations in the cerebellopontine angles of the brainstem, where lateral recesses of fourth ventricle empty, are abundant especially operations in which foramina of Luschka are used as possible access to the floor of the fourth ventricle. So awareness and knowledge of the normal anatomical features of the region is valuable for neurosurgeons. Arteries of 40 human cerebella were injected with colored gelatin to investigate the microsurgical anatomy around the foramen of Luschka in the cerebellopontine angle. Two compartments of the foramen of Luschka were distinguished, choroidal part and the patent part. Seventy-four (92.5%) of foramina were open and only 6 (7.5%) foramina were closed. The mean distance between the foramen of Luschka and the anterior inferior cerebellar artery was 3.90 mm on the left side and 3.89 on the right side. The distance from the posterior inferior cerebellar artery was 7.08 and 5.81 mm to the left and right foramina of Luschka, respectively. In ten cases, tortuous vertebral artery was occupying the left cerebellopontine angle space and the foramen of Luschka.