COMBINED TREATMENT OF SYMPTOMATIC GALLBLADDER STONES BY EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY (ESWL) AND INSTILLATION OF METHYL TERT-BUTYL ETHER (MTBE)

Twenty-four patients with symptomatic gallbladder stones (12 radiolucent and 12 calcified) were treated by a combined approach of extracorporeal shock-wave lithotripsy (ESWL) and subsequent instillation of methyl tert-butyl ether (MTBE). The patients received a mean of 1500 +/- 185 shock-wave discharges. The mean instillation time of MTBE was 13 +/- 4.2 hr. Treatment was tolerated without major adverse effects. Within a time period of three to five days eight of 12 patients with pure radiolucent stones and four of 12 with calcified stones became stone-free. After a median follow-up of five months (range: one week to 26 months), a total of 11 patients (92%) with radiolucent stones and of eight patients (66%) of those with calcified stones were free of stones, fragments, or debris. These clearance rates appear high when compared with reports on monotherapy with ESWL or MTBE, suggesting a positive effect of a combined approach in selected patients. Two patients exhibited recurrent stones after six and seven months, respectively.