Variations in the branches of basilar artery in adu lt human cadavers

Various variations of branches of the basilar arter y are mentioned in the literature but the exact cau se is not known. Anomalies of the vertebro-basilar vessels arise as early embryonic developmental deterioration. Many studies are available on the anterior circulation of the brain but studies on the posterior circulation are very f ew. Hence the present study is concentrated on morphological vari ations in branches of the basilar artery. The anterior inferior cerebellar arteries appear normal except one hypopl astic seen on left side. Many labyrinthine or inter nal auditory arteries arise from the anterior inferior cerebella r artery (60% on right and 65% on left). Numbers of the pontine branches on right side ranges from 3-7 and on left side numbers of branches are 4-7. Most of the super ior cerebellar arteries arise from the basilar artery (85% on righ t and 80% on left). Variation in the superior cereb ellar artery is unilateral duplication. Bilateral duplication of th e superior cerebellar artery and the superior cereb ellar artery arising from the posterior cerebral artery was also seen. T he posterior cerebral artery most commonly appear a s adult type (75% bilaterally), fetal type was seen more common on left side and transitional types was seen more c ommon on right side. Neurosurgical importance of this study lies during the exposure of the region for differen t purposes. Knowledge of variations will increase the success o f the surgical and radiological procedures.