A New Operation for the Treatment of Communicating Hydrocephalus

Abstract

p ATIENTS suffering from severe purulent meningitis may survive with the aid of modern antibiotic therapy only to face an equally disastrous complication, namely, obliteration of the subarachnoid fluid pathways by an adhesive process involving particularly the cisternae at the base of the brain and the subarachnoid spaces over the cerebral and cerebellar hemispheres. This chronic adhesive process may prevent access to, or virtually destroy, the normal absorptive surface provided by the vascular bed of the pia-arachnoid. The circulation of spinal fluid is therefore interrupted and progressive hydrocephalus ensues. Hydrocephalus of this origin may or may not be of the so-called variety, depending upon where interruption of the subarachnoid fluid pathways occurs. Several locations are involved commonly, and treatment varies accordingly: (1) If one foramen of Monro is occluded, unilateral hydrocephalus may occur; this has been successfully treated by making an opening through the septum pellucidum. (~) If the Sylvian aqueduct becomes blocked by scarring, but the subarachnoid cisternae remain open, subfrontal or subtemporal 3rd ventriculostomy may be performed, or even more satisfactorily, a shunting procedure of the type introduced by Torkildsen 9 which connects the lateral ventricle with the cisterna magna. (3) If obstruction occurs in the posterior fossa alone with obliteration of the cisterna magna and occlusion of the caudal and lateral recesses of the 4th ventricle, then suboccipital craniectomy with lysis of these adhesions and removal of the thickened membrane which seals the 4th ventricle may be sufficient to re-establish normal fluid circulation. (4) If, however, a more extensive adhesive process has taken place, causing obstruction of the basilar cisternae or the subarachnoid bed generally over the cerebral and cerebellar hemispheres, either alone or in addition to the locations already mentioned, then treatment becomes much more difficult. The operative procedures mentioned are of no avail since they fail to provide access to an absorptive surface. The problem becomes essentially the same as in congenital idiopathic communicating hydrocephalus where no