Microsurgical anatomy for microvascular decompression surgery

Abstract

Microvascular decompression surgery is an operation in which knowledge of normal anatomy is especially important because there are often no mass lesions in the cerebellopontine angle (CPA). There are three neurovascular complexes in the CPA, as described in the “rule of 3" (Hitotsumatsu et al. Neurosurgery 53:1436-1441, 2003). The three neurovascular complexes are associated with the three major neurovascular compression syndromes: the upper neurovascular complex including cranial nerve (CN) V and the superior cerebellar artery (SCA) is related to trigeminal neuralgia, the middle neurovascular complex including CNs VII and VIII and the anterior inferior cerebellar artery (AICA) is related to hemifacial spasm, and the lower neurovascular complex including CNs IX-XII and the posterior inferior cerebellar artery (PICA) is related to glossopharyngeal neuralgia. In this chapter, the microsurgical anatomy of the posterior fossa encountered in microvascular decompression surgery is introduced with the rule of 3.