Value of Ultrasonography and Helical Computed Tomography in the Diagnosis of Stone-Free Patients after Extracorporeal Shock Wave Lithotripsy (USG and Helical CT after SWL)

Abstract

To define the value of different radiologic modalities in determining the patients who believed to be stone-free after extracorporeal shock wave lithotripsy (SWL) with plain abdominal X-ray, by evaluating the same patients with ultrasonography (USG) and helical computed tomography (CT). Between March 2002 and February 2003, 76 patients with urolithiazis who were treated with SWL and considered to be stone-free with plain abdominal X-ray, were evaluated with USG and helical CT. The results were compared for the accuracy of the stone-free diagnosis. Residual stones were detected in 9 (11.8%) with USG and in 17 (22.3%) with CT of 76 patients who were thought to be stone-free with plain abdominal X-ray alone. Although plain abdominal X-ray has been accepted as the first line diagnostic tool in the follow-up after SWL with its cheap and practical use, helical CT was found to be more valuable in diagnosis of residual stone fragments which has not been found in plain abdominal X-ray. If we take these considerations which can change our clinical approach and patient follow-up into account, we believe that the routine use of helical CT can give more accurate information in patient controls after SWL.