Endoscopic-guided proximal catheter placement in treatment of posterior fossa cysts.

Overview

PURPOSE: Treatment of posterior fossa cysts by cystoperitoneal shunting may be complicated by a malpositioned proximal catheter located within the brainstem or cerebellum causing acute shunt malfunction or neurological deficits. We propose that proximal catheter placement from a posterior fossa approach aided by a malleable endoscope may prevent malposition and its complications. METHODS: We present 4 procedures we performed on 3 patients with posterior fossa cysts using a posterior fossa approach. In each case, the proximal catheter was molded along with a malleable endoscope to place the catheter parallel to the long axis of the fourth ventricle. Direct visualization during catheter placement insured an intracavitary position. RESULTS: Ultimately, the procedure was successful in all 3 patients as judged by intracavitary catheter position and decrease in cyst size on postoperative imaging. In 1 patient, revision using the same technique was required based upon suboptimal catheter position within one of numerous cystic compartments within the posterior fossa. There were no complications related to direct or indirect brainstem injury. CONCLUSIONS: Many posterior fossa cysts can be treated effectively and safely via a posterior fossa approach with the aid of a malleable endoscope. Direct visualization facilitates intracavitary catheter placement and orientation of the catheter in the long axis of the cyst, thereby decreasing the risk of injury to surrounding structures.