Acute Ureteric Dilatation for Ureteroscopy An Experimental Study

Abstract

The effects of three methods of acute ureteric dilatation (by graded Teflon dilators, low and high pressure balloon dilators) were evaluated radiologically, renographically and histologically in minipigs. The minipig ureter was dilated from its normal calibre of 4 F to 10 F. All three methods caused upper urinary tract dilatation and an obstructive nephropathy which had not resolved 96 h after dilatation. Histology at 24 h showed destruction of the transitional epithelium, with inflammation throughout the ureteric wall. Four weeks after dilatation the ureter was still dilated and urothelial nests were seen in the lamina propria and in the muscle coats. There was no evidence of ischaemic necrosis or ureteric stricture formation. The implications of these findings for clinical practice are discussed.

Safety and Efficacy of Same-Session Bilateral Ureteroscopy

“…Other investigators have demonstrated that ureteral stents are not needed after treatment of uncomplicated distal ureteral calculi. 13 This proposition, although at odds with current practice trends based on animal data, 14,15 was confirmed by a multi-institutional randomized trial. 3 Although we advocate "stentless" ureteroscopy for calculi throughout the urinary tract in selected patients, 6 the current study enables us to refine this evolving philosophy.…”

The role of stenting in relieving loin pain following ureteroscopic stone therapy for persisting renal colic with hydronephrosis

“…There is a belief that ureteral stent placement reduces long-term complication rates (e.g. ureteral stricture formation) [2] and short-term flank discomfort [12]. In addition, there are clinical settings in which ureteral stenting is either mandatory, such as following ureteral perforation or in cases of a solitary kidney, or recommended, including patients with renal calculi and ureteral dilatation [13,14,15] and patients with indwelling ureteral catheter preoperatively [14,15].…”

Comparison of efficacy and tolerance of short-duration open-ended ureteral catheter drainage and tamsulosin administration to indwelling double J stents following ureteroscopic removal of stones

“…2 The use of stents has proved to be beneficial as seen in various studies, because they prevent or reduce the occurrence of ureteric oedema, clot colic, and subsequent development of secondary ureteric stricture in cases with mucosal injury or difficult stones. [3][4][5] However, the use of ureteral stents is not without its attendant complications. Patients may develop flank pain, haematuria, clot retention, dysuria, frequency, and other irritative bladder symptoms following stent placement in the postoperative period.…”