Objective: To define selection criteria for optimal outcome of ESWL with oral litholysis (ursodeoxycholic acid) for gallbladder stones.
Design: Prospective study.
Setting: University hospital, Sweden.
Subjects: 145 patients with symptomatic gallbladder stones occupying a maximum of half the fasting gallbladder volume and gallbladder opacification at oral cholecystography.
Main outcome measures: Three-year stone clearance rates in relation to initial stone burden, occurrence of calcified stones, and degree of gallbladder opacification at cholecystography.
Results: At all times clearance rates according to life table analysis were significantly higher for patients whose stone volume was < or = 4.2 ml (corresponding to one stone with a diameter of < or = 2.0 cm) (83% at 3 years) than for patients whose stone volume was > 4.2 ml (67% at 3 years), and patients with one stone had significantly higher clearance rates (88% at 3 years) than patients with multiple stones (58% at 3 years). Of all patients treated for gallbladder stones during one year, 25/194 (13%) had a stone volume of < or = 4.2 ml and 16/194 (8%) a solitary stone with volume < or = 4.2 ml. Neither the degree of gallbladder opacification nor the occurrence of calcified stones influenced clearance rates.
Conclusion: ESWL may be an alternative to surgery in the few patients whose stone volume is roughly 4 ml or less and preferably have only one stone. Gallbladder function and patency of the cystic duct are poorly evaluated by oral cholecystography.