Endoluminal ultrasonography with reusable probe: Preliminary results

Background and Purpose: Endoluminal ultrasound probes have been disposable, making their regular use costly. We describe the technique and preliminary results of a reusable endoluminal ultrasound probe for examining ureteral anatomy. Patients and Methods: The 2.4-mm (7.2F) or 3-mm (9F) probe (Olympus, Tokyo) is passed up the ureter after a retrograde ureteropyelogram has been obtained. No intraoperative preparation of the probe is needed. An axial image as little as 1 cm or as much as 10 cm around the ureter can be obtained. Over the last 20 months, 50 procedures using endoluminal ultrasonography were performed in our unit: 36 (72%) for ureteropelvic junction (UPJ) obstruction, 10 (20%) for upper-tract filling defects, and the remaining 4 (8%) for ureteral strictures. Results: Endoluminal ultrasonography detected crossing vessels at the UPJ in 19 (53%) and a septum in 9 (25%) of the 36 renal units with UPJ obstruction. In eight of the 36 renal units with UPJ obstruction (22%), endopyelotomy was not done because of the presence of crossing vessels. A further 4 renal units (11%) had the direction of the incision modified because of the ultrasound findings. In the cases with upper-tract transitional-cell carcinoma, images correlated well with the nephroureterectomy specimen. The probe had to be replaced twice. Conclusions: This endoluminal ultrasound system produces clear images of the ureteral and periureteral anatomy. The reusable aspect of the probe removes an important obstacle to its common use for evaluating a variety of upper urinary tract abnormalities.