A simplified method of implanting a neuromodulator device.

Abstract

The InterStim neuromodulator device (Medtronic, Inc., Minneapolis, Minnesota) is indicated for the treatment of refractory urge incontinence, urinary frequency and urgency, and nonobstructive urinary retention. We present a modification of the 2-stage approach which is simple to perform, reduces the number of incisions from 2 to 1, decreases operative time and potentially decreases the risk of infection. Using a single paramedian incision, a quadripolar lead is placed into the appropriate sacral foramen. The lead is connected to the extension wire and the connector is anchored into an ipsilateral subcutaneous tunnel with the aid of an externalized polypropylene suture and plastic button. The extension wire is then externalized through the contralateral buttock using a subcutaneous tunneling device. At stage 2 the entire system can be removed through the original incision or the pulse generator can be implanted through a virgin incision over the connector site. A total of 20 procedures have been performed with an average stage 1 implant time of 72 minutes. Median implant time of 13 pulse generators was 36 minutes. Median explant time of 6 leads was 21 minutes. There have been no infections or adverse events. This modification is simple, efficient, safe and involves use of tools already familiar to urologists. By reducing the number of incisions, it reduces violation of the skin barrier and consequently risk of infection. Infection is potentially reduced at stage 2 because there is undisturbed, noncontused virgin tissue at the site of generator implant.