The value of ultrasound in the follow-up of patients treated with biliary lithotripsy. Implications for monitoring patients after nonsurgical therapy of gallbladder stones.

Abstract

To establish the value of ultrasound (US) in the follow-up of patients treated with extracorporeal shockwave lithotripsy (ESWL), the results of 484 US examinations of 87 patients were analyzed and related to the results of ESWL. Reliability of US in assessing efficacy was investigated by comparing consecutive US examinations. Unreliable US results were found in 36 patients (41%); in 7 patients US failed to demonstrate fragments. In nine patients (10%) unreliable US findings contributed to delayed retreatment with ESWL. To prevent errors in treatment regimen, verification of US findings is advised in case no fragments or fragments < 5 mm are found. In 22 patients (25%) US findings appeared indicative of hampered stone migration. Only 2 of these 22 patients (9.1%) became free of stones, compared with 32 of the remaining 65 patients (49.3%) (p < 0.01), even though both groups had similar initial stone characteristics and similar time of follow-up. US findings such as a contracted gallbladder or a common bile duct > 7 mm therefore indicate poor efficacy of ESWL.