Why can’t shock wave lithotripsy be used for lower ureteral stones?

In clinical practice, it is found that extracorporeal shock wave lithotripsy cannot be performed for lower ureteral stones, mainly because the intestine obscures the anterior end of the ureter and extracorporeal shock wave lithotripsy cannot achieve lithotripsy. If end ureteral stones are accompanied by end ureteral stenosis, cystoureteroscopic lithotripsy is also not easy to perform, and dilatation of the stenotic segment of the ureter is required prior to treatment. For simple end ureteral stones, ureteroscopic holmium laser lithotripsy can be performed. Adequate evaluation is required before lithotripsy is performed, and the obstruction is relieved by holmium laser lithotripsy. In some cases, end ureteral stones require a certain amount of time for conservative observation and treatment, which requires more than 2 weeks of local observation and can be resolved by self-discharge. However, on top of the conservative treatment, it should be ensured that the diameter of the ureteral stone is less than 6mm, because the narrowest point at the end of the ureter is about 5mm, and only stones below 6mm can be expelled by conservative treatment. In this case, patients are advised to have a CT examination of the urinary system to clarify the exact size of the stone at the end of the ureter.