EVALUATION OF OPTIMAL STENT SIZE AFTER ENDOUROLOGICAL INCISION OF URETERAL STRICTURES

The stent size necessary to promote optimal ureteral healing after an endoureterotomy is not known. We compared healing of an endoureterotom y over a 7F indwelling ureteral stent with healing over a 14F endopyel otomy stent. A midureteral stricture was created in each of 25 anesthe tized female minipigs using an electrified stone basket passed retrogr ade. Six weeks later, the stricture was incised with a 24F cutting bal loon device. Twenty pigs were randomized to receive a 7F or a 14F sten t; four control pigs received neither incisions nor stents. At 1 week, a radiograph was performed to confirm proper stent position, and the stents were removed. At 3 months, a retrograde ureterogram was perform ed, and the ureters were examined grossly and harvested for histologic studies. Two of the ten pigs in each study group developed a recurren t stricture. The use of a 14F stent provided no advantage over the use of a smaller, more easily positioned 7F stent.