Comparison of holmium and flashlamp pumped dye lasers for use in lithotripsy of biliary calculi.

The characteristics of laser lithotripsy of biliary calculi are compared for a flashlamp pumped dye laser (lambda = 640 nm) and a Cr:Tm:Ho-YAG laser (lambda = 2.1 microns). Data on fragmentation efficiency with respect to laser power and pulse repetition rate are presented for different types of stones. It is shown that both lasers can produce effective stone fragmentation. The laser power required for efficient fragmentation characteristics is significantly less for the visible wavelength laser. However, the problems associated with damage to the fiber tips of the delivery system during operation were found to be less with the near infrared wavelength. The laser power for efficient fragmentation with the dye laser varies significantly for different types of stones while the power for efficient fragmentation with the holmium laser is the same for all stones.