Abstract
in vitro CT scans were performed on 48 gallstones removed at surgery. Disintegration of these stones by a piezoelectric lithotripter (ESL-500A, Toshiba) was followed, until all fragments measured 2 mm or less in diameter. Some fragments were subjected to chemical analysis. The CT image appearances were categorized as follows: isodense, faint, rimmed, laminated and dense patterns. The mean and maximal CT-values, the, percentages of cholesterol or calcium contents, and the number of shock waves to complete disintegration were compared with CT patterns. The cholesterol contents of isodense, rimmed, and laminated groups were more than 80% and the number of shock waves per stone volume did not differ among these groups. The dense pattern group showed the poorest efficiency for the number of shock waves. As CT analysis, of gallstones can be a reliable prediction of gallstone chemical composition and its structure, CT image appearance can be predictive for fragmentation outcome.
