












Key
AICA: anterior inferior cerebellar artery
AChA: anterior choroidal artery
ASA: anterior spinal artery
Basilar: basilar artery
PICA: posterior inferior cerebellar artery
PCA: posterior cerebral artery
PSA: posterior spinal artery
SCA: superior cerebellar artery
VA: vertebral artery
Original work of Craig Hacking.
Case Discussion
There is extensive variation in the arterial supply of the structures of the brainstem. These diagrams are based on a collection of resources and are not intended to be used as a definitive reference, rather a general guide to the vascular territories. Obviously in individual patients, the size of the components of the circle of Willis will determine specific territories.
Key
AICA: anterior inferior cerebellar artery
AChA: anterior choroidal artery
ASA: anterior spinal artery
Basilar: basilar artery
PICA: posterior inferior cerebellar artery
PCA: posterior cerebral artery
PSA: posterior spinal artery
SCA: superior cerebellar artery
VA: vertebral artery