Direct dissolution of gallstones with methyl tert-butyl ether by endoscopic cannulation of the gallbladder.

Methyl tert-butyl ether (MTBE) rapidly and effectively dissolves cholesterol gallbladder stones. Due to the invasive nature of transhepatic catheterization, we studied the safety and efficacy of MTBE stone dissolution, delivered by endoscopic, retrograde cannulation of the gallbladder. Extracorporeal shock-wave lithotripsy (ESWL) was employed in patients with multiple stones, to increase contact surface area and facilitate dissolution. We successfully cannulated the gallbladder in 13/17 patients (76.5%) attempted, with no associated complications. After cannulation, MTBE lysis was then conducted on all patients, and 10/13 patients (77%) cannulated were either stone-free at completion, or had only residual gallbladder sludge. Predissolution ESWL successfully fragmented stones in 6/7 patients (86%) in which it was attempted. Both ESWL and MTBE were well tolerated by all patients. Endoscopic retrograde cannulation of the gallbladder and MTBE dissolution is a promising alternative for the treatment of gallbladder stones in patients who will not receive surgery.