Magnified endoscopic view of porus of right internal auditory meatus. Petrosal and clival bone have been removed to expose the anterolateral pons and opening of the internal auditory canal. A portion of the anterior inferior cerebellar artery can be seen looping toward the internal auditory meatus in company with the facial and vestibulocochlear nerves. A portion of the vein of the middle cerebellar peduncle is also in view. (Image courtesy of AL Rhoton, Jr.)