Placement of Ommaya Reservoirs using Electromagnetic Neuronavigation and Neuroendoscopy: A retrospective study with cost-benefit analysis.

OBJECTIVE: Placement of intraventricular catheters in oncology patients is associated with high complication rates. Placing Ommaya reservoirs with the Zero-Error Precision Protocol (ZEPP), a combination of neuronavigation (AxiEM stealth frameless neuronavigation system) and direct verification of catheter tip placement with a flexible neuroendoscope is associated with decreased complication rates as a result of increased catheter placement accuracy. However, ZEPP costs more than traditional methods of catheter placement and the question of whether this increased accuracy with ZEPP is cost-effective is unknown METHODS: We performed a single-center retrospective chart review of 50 consecutive Ommaya reservoir patient placements between 2010 and 2017. Twenty-five ventricular catheters were placed using the ZEPP protocol and 25 ventricular catheters were placed using only AxiEM stealth navigation. Postoperative catheter accuracy and complication rates were assessed. A cost-benefit analysis was then conducted to determine if the overall cost for placing ommayas with ZEPP was effective compared to the alternative method of using neuronavigation alone.

RESULTS: In the non-ZEPP cohort, 10/25 catheters were placed within the optimal location compared to 25/25 catheters placed in with the ZEPP cohort. Three complications occurred in the non-ZEPP cohort: two malpositioned catheters requiring surgical revision and one catheter related hemorrhage resulting in a prolonged stay in the intensive care unit. No complications occurred in the ZEPP cohort. A Cost-benefit analysis showed $4,784 savings (US dollars) per patient with ZEPP utilization due to the high complication-associated costs.

CONCLUSIONS: Implementation of a combined neuronavigation and neuroendoscopic protocol (ZEPP) for verifying ventricular catheter placement in Ommaya reservoirs improved catheter tip accuracy, resulted in lower complication rates, and was more cost-effective when compared to the non-ZEPP cohort who used only neuronavigation. ZEPP can be used for ventricular shunt catheter placement in order to decrease complications and verify catheter tip accuracy in Ommaya or standard ventriculoperitoneal shunts.