Ommaya reservoirs for the treatment of leptomeningeal metastases.

ABSTRACT

OBJECTIVE: Ommaya reservoirs are frequently used to deliver intraventricular chemotherapy in cancer patients with leptomeningeal metastases. We review techniques of catheter placement and complication avoidance. METHODS: Between January 1995 and June 1998, Ommaya reservoirs were placed in 107 patients for the treatment or prophylaxis of leptomeningeal metastases at the Memorial Sloan-Kettering Cancer Center. Patients with slit ventricles (total, 25) underwent preoperative pneumoencephalography for ventricular dilation. Intraoperative fluoroscopic guidance was used in 77 patients to confirm the catheter tip position at the foramen of Monro. Other intraoperative aids included endoscopy in 21 patients, ultrasound in 7, and stereotaxy in 6. No aids were used in 3 patients, more than one aid was used in 9, and the technique could not be determined retrospectively in 3. RESULTS: The median survival of patients treated for leptomeningeal metastases was 9 months (Kaplan-Meier method). Eight patients developed hydrocephalus requiring conversion of the Ommaya reservoir to a ventriculoperitoneal shunt and precluding delivery of chemotherapeutic agents. An additional 11 patients referred for Ommaya reservoir placement demonstrated elevated intracranial pressure requiring an initial ventriculoperitoneal shunt. Complications of Ommaya reservoir placement occurred in 10 patients (9.3%) and included two infections, five catheter malpositions, and three intracranial hemorrhages. Two deaths occurred secondary to intracranial hemorrhage one after postoperative anticoagulation for a mechanical heart valve, and one attributed to treatment-related thrombocytopenia. Nine patients (8.4%) had treatment-related imaging abnormalities; seven were asymptomatic and two developed symptomatic leukoencephalopathy. CONCLUSION: Complications associated with Ommaya reservoirs can be minimized by intraoperative confirmation of the catheter position with fluoroscopic guidance and/or endoscopy. We recommend postoperative computed tomographic scans before initiation of intraventricular chemotherapy. Patients with elevated intracranial pressure may require shunting procedures in lieu of Ommaya reservoir placement.