Radiographic imaging of the artificial urinary sphincter pressure regulating balloon

Purpose: Radiography of the artificial urinary sphincter is done for the postoperative evaluation of recurrent incontinence. We investigated the ability of urologists and radiologists to detect changes in the radiographic appearance of the pressure regulating balloon at various volumes of contrast solution. Materials and Methods: We obtained 20 sequential radiographs of a pressure regulating balloon lying atop the pelvic region of a body phantom. The volume of contrast solution within the balloon was decreased by 1 cc in each radiograph from 20 to 1 cc. Urologists and radiologists examined the radiographs for changes in balloon size, density and circularity. Radiographs were reviewed in side-by-side comparison with a baseline radiograph and also independently without reference to baseline study. Results: On side-by-side comparison changes in balloon size, density and circularity were first seen at 17, 13 and 8 cc of contrast solution, respectively. On independent review changes in size, density and circularity were first seen at 10, 8 and 6 cc, respectively. Conclusions: If there are no contraindications, contrast solution should be used to fill the balloon component of the artificial urinary sphincter system. Immediately after implantation a baseline radiograph should be obtained. Without a baseline film for comparison radiographic imaging of the balloon does not detect changes until at least 50% of its volume has been lost, Because comparison imaging is invaluable for detecting volume loss, a radiograph should be obtained immediately after initial placement of the artificial urinary sphincter.