Two Approaches to the Anterior Third Ventricle

Abstract

Attempts to remove a brain tumor in the anterior third ventricle are hampered by the surgeons inability to expose the cavity of the ventricle widely. An option is to enlarge the foramen of Monro posteriorly, but here the internal cerebral vein, which is formed by the joining of the thalamostriate and septal veins, is in the way. We believe that dividing either the septal vein or the thalamostriate vein carries no important risk because adequate collateral circulation exists between the superficial cortical and deep medullary venous systems that drain the posterior frontal and basal ganglion regions. Hirsch et al. as well as DeLandsheer et al. emphasize that one thalamostriate vein could be divided without risk (DeLandsheer et al. 1978; Hirsch et al. 1979). Our experience with fourteen third ventricle tumors operated on during the last five years supports the notion that this approach will give wide exposure to the third ventricle with safety (Lavyne and Patterson 1983).