G, The left basal and internal cerebral veins have been elevated and the vein of the cerebellomesencephalic fissure, which is joined by a superior vermian vein, has been retracted to the right to expose the superior colliculus, pineal, and splenium. H, The tela choroidea attached to the upper surface of the pineal has been opened to expose the posterior part of the third ventricle. I, Retraction for the paramedian approach has been shifted to the left of the vermis. J, The left internal cerebral and internal occipital veins have been retracted to expose the posterior part of the splenium, the pineal and the superior and inferior colliculi, and the branches of the PCA and SCA exiting the ambient cistern. K, Enlarged view. The exposure has been shifted to where the PCA exits the ambient cistern. L, The paramedian approach provides easier access to the superior and inferior colliculi and requires less retraction than is needed to expose these structures in the approach directed in the midline above the apex of the tentorial cerebellar surface. (Images courtesy of AL Rhoton, Jr.)