Anterior surface of pons with associated neurovasculature. The pons and proximal medulla are in view along with lateral portions of the cerebellum. The vertebral arteries join near the pontomedullary junction to form the basilar artery. The posterior inferior cerebellar arteries are the largest branches of the vertebral arteries and are one of three pairs of vessels supplying the cerebellum. The left posterior inferior cerebellar artery is seen wrapping around the lower lateral surface of the medulla to the posterior inferior surface of the cerebellum. Two other cerebellar arteries, the anterior inferior and superior cerebellar arteries, arise respectively from caudal and rostral portions of the basilar artery and course to their destinations on the cerebellum. Between these branches arise smaller pontine arteries that course transversely on the pons. The trochlear nerve emerges from the dorsal surface of the midbrain while the oculomotor nerve emerges from its anterior surface. The latter nerve passes between the superior cerebellar and terminal posterior cerebral arteries. The trigeminal nerve emerges from the anterolateral surface of the pons. The facial and vestibulocochlear nerves emerge along the lateral aspect of the pontomedullary junction in proximity of the choroid plexus of the fourth ventricle. Anterior and medial at this junction arise the abducens nerves. The glossopharyngeal nerves can be seen emerging from the lateral surface of the proximal medulla. (Image courtesy of PA Rubino)