Bilaterally absent posterior inferior cerebellar artery: case report.

Posterior inferior cerebellar artery (PICA) is one of the cerebellar arteries which originates from the vertebral artery and has the most complex and variable course. The PICA usually originates from the vertebral artery intracranially as a single trunk, however, absent, double trunk, extracranial, and extradural PICA may also exist. In a collection of 50 cerebellar specimens (100 hemispheres) injected with colored gelatin, one case of bilaterally absent PICA was encountered, male aged 59 (causes of the death was not taken into consideration).