Transhepatic topical dissolution of gallbladder stones with MTBE and EDTA. Results, side effects, and correlation with CT imaging.

Forty-two patients with symptomatic gallstones (28 women, 14 men, mean age 49.8 +/- 13.2 years) were recruited for contact dissolution therapy. Pretreatment CT scans of the gallbladder were obtained in every patient under standard conditions. For contact dissolution treatment of heterogeneous gallstones or gallstones with attenuation values of more than 50 Hounsfield units, methyl tert-butyl ether and bile acid ethylene diaminetetraacetic acid were used in alternating administration at time intervals and durations adapted to the individual tolerance of the patients. In the case of gallstones with mean attenuation values under 50 Hounsfield units, the dissolution therapy was performed with methyl tert-butyl ether alone. In 12 (28.6%) patients a complete dissolution of gallbladder stones could be achieved; 11 patients (26.2%) revealed gallbladder sludge but no radiologically or sonographically visualized residual stone debris. The remaining 19 (45.2%) patients had residual gallstone debris. Shell fragments in three of five rimmed gallstones, seven of eight laminated gallstones, and all densely calcified stones were refractory to contact dissolution therapy. Dissolution rates correlated well with mean attenuation values, whereas no significant correlation was found between stone number and dissolution rates or between stone diameter and dissolution rates respectively. The mean instillation time required for stones with a mean density of more than 50 HU was 17.7 +/- 11.5 hr of bile acid ethylene diaminetetraacetic acid and 5.8 +/- 3.2 hr of methyl tert-butyl ether. In the case of isodense stones, the average instillation time of methyl tert-butyl ether was 12.3 +/- 4.7 hr.(ABSTRACT TRUNCATED AT 250 WORDS)