In-situ monitoring of the mid-IR laser ablation of cataract-suffered human lens by optical coherent tomography

We have designed a laser complex which is a combination of a YAG:Er laser operating in the free-running mode, a radiation delivery system based on a chalcogenide fiber with uniquely high damage threshold, and a diagnostic optical coherent tomography (OCT) device for in situ monitoring of surface layers of the tissue under treatment. A flexible chalcogenide glass multimode fiber operates with a pulse energy of 150 mJ at a repetition rate of 3 Hz. Neither degradation nor laser damage were observed after transmission of 104 laser pulses through the fiber delivery instrument. This complex was employed to study the effect of the radiation of a YAG:Er laser and some other mid-IR lasers on a cataract-suffered human lens. The pulse- to-pulse kinetics of the laser tissue treatment process with a scanning depth of several millimeters and spatial resolution of 15 micrometers was investigated.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.