Identification of Urinary Stone Composition by Pulsed Dye Laser

Stones were recovered from the urinary tract and their composition determined by X-ray diffraction before exposure to a pulsed dye laser beam. The resultant fluorescent emissions were recorded using a scanning reticon and they appeared to be specifically related to the composition of each stone. This technique has a practical application as it may allow identification of the composition of urinary tract stones in vivo, and so indicate the best mode of lithotripsy.