In a careful summary of the literature, T. H. Weisenburg1 collected thirty cases of tumor of the third ventricle, and, by a review of the clinical and pathlogic findings, established a syndrome. He distinguishes three symptomatic groups:
Those cases in which a tumor of a moderate size is situated in the floor of the third ventricle, and in which there is no extension into the foramen of Monro or aqueduct of Sylvius.
Small tumors so situated as to obstruct the foramen of Monro and whose position can be changed by deviation of the head.
Those tumors, whether large or small, which either extend into the aqueduct of Sylvius, affecting the surrounding structures by direct extension or pressure, or those in which the posterior portions of the cerebral peduncles and pons are compressed, either by direct pressure or by dilatation of the aqueduct of Sylvius.
The first class does not
POLLOCK LJ. TUMOR OF THE THIRD VENTRICLE. JAMA. 1915;LXIV(23):1903-1905. doi:10.1001/jama.1915.02570490019009