[Extracorporeal shockwave lithotripsy for upper urinary tract stone].

Extracorporeal shockwave lithotripsy (ESWL) is the fragmentation of stone by means of acoustic shockwaves created by an extracorporeal source. ESWL brakes the stone by spallation and squeezing. The optimal frequency for fragmentation is 1Hz. The initial power must be low, then progressively increased during the session. The contra-indications for ESWL are pregnancy, major deformities, severe obesity, aortic aneurism, uncontrolled coagulation disorders, untreated urinary infection, cardiac pacemaker. A stone density of 1000UH is a risk factor for fragmentation failure. The success rate for the kidney and the ureter is 60-80% and 80%, respectively. Stone clearance may be facilitated by alpha blockers. Asymptomatic and non-infected residual fragments less than 4mm must be followed-up annually.