Technique and application of endoluminal ultrasonography using a flexible cystoscope

We evaluated endoluminal ultrasonographic imaging of urinary tract disease. Between December 1998 and September 1999, we diagnosed the clinical staging of 30 patients with bladder tumors and 6 patients with ureteral tumors by using endoluminal ultrasonography. Two patients underwent endoluminal ultrasonography to examine whether aberrant vessels exist around the ureteropelvic junction obstruction. The flexible cystoscope has a channel of 2 mm in diameter. The miniature flexible ultrasound transduser of the endoluminal ultrasonography we used is 1.7 or 2 mm in diameter supplies 360 degree real-time cross-section images. This probe can pass through a channel. This procedure was performed by transurethral manipulation. Bladder tumors of 23 patients were pathologically staged as ≤ T1. We diagnosed 19 (83%) of the 23 tumors correctly before surgery using endoluminal ultrasonography. In 6 patients with a ≤ pT1 ureteral tumor, we diagnosed 3 patients correctly as ultrasonic staging ≤ T1. However in the other 3 patients, ultrasonic staging could not be obtained because the ultrasound probe was unable to reach the tumor probably due to invasive growth of the tumor or a severe kink in the ureter. In 2 patients with ureteropelvic junction obstruction, aberrant vessels were not found ultrasonographically. The absence of such aberrant vessels was confirmed at operation. There have been no complications related to the procedure of endoluminal ultrasonography. The technique of endoluminal ultrasonography using a flexible cystoscope is considered to be simple, painless, stressless, safe, and reliable, with a low-risk of mucosal damage.