在应用体外冲击波粉碎肾及输尿管结石的过程中，最常遇到的困难是：肾结石较大者，碎石后容易形成“石串”，从而寻致肾积水、感染以致肾积脓等；输尿管结石在原位长期滞留，以致冲击波难以粉碎或震碎后不能排出。我院自1993年10月～1996年10月采用碎石前放置双J管的方法，减少 In the process of using ESW to crush kidney and ureteral calculi, the most common difficulties encountered are: the larger the kidney stones, the easy formation of “stone strings” after the gravel, resulting in hydronephrosis, pyogenetic infection and so on ; Ureteral stones in place long-term retention, so that the shock wave is hard to crush or shattered can not be discharged. Our hospital from October 1993 to October 1996 before the placement of double J tube gravel method to reduce