Endourology & laparoscopy

Abstract

Editorial CommentWith dramatic improvements in endoscope design and instrumentation have come expanded indications for endoscopic stone management such that large and complex renal calculi are increasing managed ureteroscopically. However, the treatment of larger stones is associated with longer operative times and a greater potential for fluid absorption and/or bacteremia. A recent cadaveric study assessed renal pelvic and ureteral flow characteristics during flexible ureteroscopy either with or without a ureteral access sheath and determined that use of a ureteral access sheath was associated with low intrarenal pelvic pressures regardless of irrigation pressure used, and significantly lower pressures with ureteroscopy at all locations in the ureter compared with ureteroscopy using a bare ureteroscope (1).Auge and colleagues validated the findings of this cadaveric study in a clinical study of 5 patients with nephrostomy tubes who underwent flexible ureteroscopy for management of obstructing ureteral calculi. Measuring renal pelvic pressures via the nephrostomy tube during ureteroscopy either without or with a ureteral access sheath yielded differences of 45 mm Hg, 48.1 mm Hg, 55.2 mm Hg and 53.8 mm Hg with the ureteroscope in the distal ureter, middle ureter, proximal ureter and renal pelvis, respectively. As such, use of a ureteral access sheath is more than just a mere convenience, facilitating retrieval of stone fragments or passage of the ureteroscope. Instead it provides a safety mechanism, particularly during lengthy procedures or when the occurrence of pyelovenous or pyelolymphatic backflow poses the greatest risk, such as during the treatment of urothelial tumors or potentially infected stones. Purpose: We evaluated the durability of endourological intervention for ureteropelvic junction obstruction and established guidelines for postoperative surveillance.Materials and Methods: Since 1989, 150 patients have undergone endourological intervention for ureteropelvic junction obstruction, of whom 127 (53 men and 74 women) 13 to 79 years old (mean age 40.4) underwent postoperative evaluation at our center. These 127 patients are the study group reported. Endourological management consisted of hot wire balloon endopyelotomy in 25 patients, percutaneous endopyelotomy in 67 and ureteroscopic laser endopyelotomy in 35. Success in this study was strictly defined as symptomatic relief plus radiographic resolution on excretory urogram and/or diuretic renogram. Statistical analysis was performed to assess mean time to failure and develop Kaplan-Meier re-stenosis-free survival estimates.