Treatment of Ureteral Stone using Modulith SL-20 : Analysis of the Factors influencing on Stone Fragmentation

Lee, Gil Ho; Kim, Hyung Jee

Abstract

Extracorporeal shock wave lithotripsy (ESWL) is a golden standard to treatment of symptomatic urinary calculi. Many experiences treated with ESWL has been reported in worldwide literatures. But there are a little reports which analyze factors influencing on successful stone fragmentation with ESWL. We reviewed 136 patients with primary ureteral calculi treated with the third generation lithotripter, Modulith SL-20, to analyze the factors influencing on stone fragmentation and to determine the limit of repeated ESWL. The results were as follows: 1.The cumulative successful rates of the first, second, third, 4th and 8th session were 72%, 90%, 96%, 98% and 98%, respectively. Any successful stone fragmentation is not seen after the 5th session. 2.The more the size of calculi increase, the more the numbers of repeated ESWL are increased (p=0.001). 3.The number of repeated ESWL for successful fragmentation increase in radio-opaque calculi than slightly opaque calculi (p=0.001). 4.The location of calculi is not correlated to the numbers of repeated ESWL for successful fragmentation (p=0.09). 5.The degree of ureteral obstruction is not correlated to the numbers of repeated lithotripsies for successful fragmentation (p=0.28). It could be concluded that the size and radio-opacity of calculi are well correlated to the numbers of repeated lithotripsies for successful fragmentation, whereas the location and the degree of ureteral obstruction are not.