Abstract
This study evaluates the pulsed tunable dye laser with wavelength 504 nm, frequency 10 Hz, and pulse width 1.2 μs for cholelitholysis. Power of 10-40 kW was directed through a 250-pm quartz fiber optic to ablate 55 gallstones. The fiber was positioned in direct contact with the stones under saline. Power delivery was begun at 10 kW and increased in 10-kW increments until litholysis began. The range of power and energy necessary to fragment the gallstones was evaluated on four common bile ducts fresh autopsy specimens). Following fragmentation, all stones were analyzed. There were 35 cholesterol stones and 20 bilirubin stones. Size ranged from 0.012 to 7.56 cm3. Energy necessary for fragmentation ranged from 0.4 to 11.2 J. Power necessary for fragmentation was 20 kW for 2/55 stones and 40 kW for 53/55 stones. At 40 kW, common bile duct perforation occurred within 1.1 ± 0.1 s. The pulsed tunable dye laser can fragment gallstones of all compositions. The threshold for fragmentation is 40 kW, but common bile duct perforation occurs at this power. We conclude that laser radiation sufficient to fragment gallstones can injure the common bile duct. © 1991 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.