Can we predict the need for intervention in steinstrasse following shock wave lithotripsy?

INTRODUCTION: Steinstrasse (SS) is a known complication of shock wave lithotripsy (SWL). Although the majority of SS clears spontaneously, about 6% require intervention. This study was carried out to identify the factors that determine the need for intervention in SS. MATERIALS AND METHODS: This was a retrospective study of all patients who developed steinstrasse following SWL at our center. They were divided into two groups: a) Those cleared spontaneously and b) Those required intervention. The two groups were compared with regard to demographic profile, stone factors and factors related to steinstrasse. RESULTS: Out of 2436 cases of SWL, 89 (3%) formed steinstrasse. The majority of the patients (35%) who required intervention had stone sizes of 10-14 mm. Coptcoat type III steinstrasse required significantly more interventions for clearance (P = 0.001). The site and the size of the SS was not a predictor of intervention for SS. CONCLUSIONS: Early intervention is warranted in patients with steinstrasse where the lead fragment is >5 mm (Coptcoat type III).