Diagnosis and surgical treatment of choroid plexus papillomas.

This is a report of 22 cases of papillomas of the choroid plexus diagnosed and managed personally by the author. The angiographic diagnosis and extension of choroid plexus papillomas are described, as is the surgical technique for removing these tumors from the lateral, third, and fourth ventricles. Specific attention is given to using the angiogram as the study of choice upon which surgical technique is planned. The diagnosis of choroid plexus papilloma of the lateral ventricle is made by observing the presence of a hypertrophied anterior choroidal artery, a 'double tumor' sign with one tumor at the trigone and the other within the temporal or frontal horn, tumor stain at the trigone, and asymmetrical hydrocephalus, generally, with a shift away from the side of the larger ventricle. Posterior fossa papillomas cause symmetrical hydrocephalus and generally have tumor stain located within the midline, with the major feeding coming from either the superior cerebellar or the posteroinferior cerebellar arteries. Surgical removal of the tumor should entail an 'en bloc' resection following occlusion of the feeding and draining vessels. The tumor should be removed directly when it is in the lateral ventricle and following ventriculocerebral spinal fluid shunting when it is in the posterior fossa.