Arteriovenous malformations of the superior cerebellar artery: excision via an occipital transtentorial approach.

Arteriovenous malformations (AVMs) of the superior cerebellar artery (SCA) are unusual and difficult lesions to treat, representing less than half of all AVMs located in the posterior fossa. Traditional approaches for surgical extirpation include the subtemporal transtentorial and suboccipital supracerebellar routes. On the basis of our recent experience with three SCA-supplied AVMs, we advocate an occipital transtentorial approach similar to that used for neoplasms of the pineal gland. Exposure of the AVM from above and in the midline provides superior visualization of the deep veins, the SCA arborization in the retrocollicular space, and the rostral cerebellum, without exposing the temporal lobe and the 4th nerve to surgical trauma in a narrow, confined space. Superior cerebellar AVMs that arise from the caudal branch of the SCA on the superolateral aspect of the hemisphere are more easily handled by standard suboccipital methods.