Placement of Ommaya Reservoirs Using Electromagnetic Neuronavigation and Neuroendoscopy: A Retrospective Study with Cost-Benefit Analysis.

Background: 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 stereotactic navigation) 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, the ZEPP costs more than traditional methods of catheter placement, and the question of whether this increased accuracy with the 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 Ommaya reservoirs with the ZEPP was effective compared with the alternative method of using neuronavigation alone.

Results: In the non-ZEPP cohort, 10 of 25 catheters were placed within the optimal location compared with 25 of 25 catheters placed in the ZEPP cohort. Three complications occurred in the non-ZEPP cohort: 2 malpositioned catheters required surgical revision and 1 catheter-related hemorrhage resulted in a prolonged stay in the intensive care unit. No complications occurred in the ZEPP cohort. A cost-benefit analysis showed $4784 savings per patient with ZEPP utilization because of the high complication-associated costs.

Conclusions: Implementation of the 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 with the non-ZEPP cohort, which used only neuronavigation. The ZEPP can be used for ventricular shunt catheter placement to decrease complications and verify catheter tip accuracy in Ommaya or standard ventriculoperitoneal shunts.