The superior cerebellar artery (SCA) arises from the distal basilar artery, just below the posterior cerebral artery (PCA) and typically supplies:
- whole superior surface of the cerebellar hemispheres down to the great horizontal fissure
- superior vermis
- dentate nucleus
- most of the cerebellar white matter
- parts of the midbrain
- superior cerebellar peduncle
- middle cerebellar peduncle
Unlike the anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA) the SCA is rarely absent. It is frequently duplicated:
- unilateral duplication: 28%
- bilateral duplication: 8%
- triplication: 2%
The upper branch, when multiple, may arise from the PCA and usually supplies the vermis, whereas the lower branch supplies the hemisphere.
Segments
- anterior pontine (or prepontine) segment
- courses laterally from its origin within the prepontine cistern
- runs alongside the oculomotor nerve, which separates it from the first segment of the PCA
- ambient segment
- begins at the lateral margin of the pons coursing posteriorly through the ambient cistern
- turns posteriorly over the middle cerebellar peduncle
- runs alongside the trochlear nerve
- quadrigeminal segment
- located in the lateral portion of the quadrigeminal cistern
- approaches the contralateral SCA near the midline
Branches
- perforating branches
- pons
- midbrain
- inferior colliculus
- lateral (marginal) branch
- largest branch of the SCA
- usually arises from the ambient segment
- runs posteriorly in the region of the interhemispheric fissure
- gives off hemispheric branches that course superiorly over the superior cerebellar hemisphere
- hemispheric branches
- arise from the lateral (marginal) branch and from the SCA distal to the origin of the lateral branch also from the ambient segment
- supplies dentate nucleus
- superior vermis
- medial quadrigeminal lobule
- superior semilunar lobule
- superior vermian
- terminal branch(es) of the SCA
- anastomose with inferior vermian branches of the PICA
