Territory of anterior inferior cerebellar artery (AICA)

The AICA has a variable origin, course and supply, and is not present on 40% of people. The amount of tissue supplied by the AICA is variable (PICA-AICA dominance) but usually includes:

• middle cerebellar peduncle
• inferolateral portion of the pons
• flocculus
• anteroinferior surface of the cerebellum

Stroke pattern:

Pure AICA infarcts are rare, they mainly occur with other territories involved. They frequently have a concomitant pontine infarct. There is 4 major patterns:

• Coma with tetraplegia (pontine infarct)
• Classic AICA syndrome: ipsilateral involvement of the V, VII and VIII cranial nerves with hearing loss, vertigo, vomiting, tinnitus, facial palsy and facial sensory loss, Horner syndrome, appendicular ataxia, contralateral temperature and pain sensory loss
• Pure vestibular syndrome (isolated vertigo)
• Isolated cerebellar signs