In vitro evaluation of gallstone dissolution with methyl-tert-butyl ether and ultrasound energy.
Given the large number of cholecystectomies performed annually, a nonsurgical approach to gallstone therapy is of great interest. A laboratory ultrasound system has been developed to study enhancement of methyl-tert-butyl ether (MTBE) dissolution of human gallstones in vitro. A mathematical model that quantitatively characterizes the dissolution process via a rate constant has been developed. Using this model, the kinetics of 15 gallstones from a single patient were evaluated for three dissolution methods: 1) unstirred MTBE, 2) aspirated MTBE, and 3) ultrasonically enhanced MTBE. The results showed excellent fits between the model and measured dissolution rates. 195 kHz continuous-wave (CW) ultrasonically enhanced dissolution rates exhibited a 6.2 fold gain over the manually aspirated MTBE and a 49.5 fold gain over static MTBE dissolution. Investigation of 50% duty cycle pulsed mode ultrasound revealed that total power appears to be the determinant of the observed dissolution rates. Gallstone calcification showed a strong correlation with dissolution rates measured by the model.
McKinley
C A
CA
Ontario Cancer Institute, University of Toronto, Canada.
Hunt
J W
JW
Ricketts
J
J
Lu
D S
DS
Ho
C S
CS
Foster
F S
FS
D002769:Cholelithiasis / Q000188:drug therapy / Q000628:therapy*; D003131:Combined Modality Therapy; D004987:Ethers / Q000627:therapeutic use*; D005069:Evaluation Studies as Topic; D006801:Humans; D066298:In Vitro Techniques; D008738:Methyl Ethers; D012997:Solvents / Q000627:therapeutic use; D014464:Ultrasonic Therapy
D004987:Ethers; D008738:Methyl Ethers; D012997:Solvents; C043243:methyl tert-butyl ether