Artificial Urinary Sphincter Revision: The Role of Ultrasound

Abstract

To assess the accuracy of office-based ultrasound (US) to identify the fluid status of the AMS 800 artificial urinary sphincter (AUS) pressure-regulating balloon (PRB). Patients who underwent AUS revision surgery (removal/replacement) from January 4, 2007, to January 4, 2010, were identified. US were done preoperatively to assess the system fluid status. Intraoperative findings were recorded. Sensitivity and specificity were calculated comparing US results with intra-/postoperative findings. When the PRB was underfilled, the location of the device fluid leak was determined, and the device was removed/replaced. In cases of a full PRB, patients had a cuff downsizing or total removal/replacement. A total of 27 patients were identified. Reasons for not obtaining US included: advanced device age (4), cuff erosion (2), volume determination by other modality (2), cuff site pain (1), isolated pump malfunctions (1), and other (3). Fourteen patients underwent an US before the removal/replacement. By US, PRB was full (21-23 mL) in 43% of the patients and empty/underfilled (0-6 mL) in 57%. US was 100% sensitive and specific determining fluid status. When PRB was full, management consisted of cuff downsizing (3), transcorporal cuff placement (1), and total removal/replacement (2). In all cases of device leak, an entire removal/replacement was performed. The cuff was identified as the site of leak in 50% of cases. US is an effective and accurate way of determining the fluid status of the AMS 800 AUS. Given the accuracy of this modality, the system can be filled with saline solution without losing the ability to determine fluid status.