Semiconductor diode laser endophotocoagulation.

We successfully used a semiconductor diode laser to deliver endophotocoagulation burns to the retina of a rabbit. The diode laser employed emits light at a wavelength of 817 nm (near infrared). It has a power output of up to 1.0 W in the continuous-wave mode, equivalent to the capability of current argon laser endophotocoagulators. A standard, commercially available fiberoptic endophotocoagulation probe was used to deliver the laser burns. We used power settings ranging from 300 mW to 400 mW and exposure times of 0.1 to 0.2 seconds to produce chorioretinal burns that appeared clinically and histopathologically indistinguishable from those induced with conventional wavelengths. This new laser system has the decided advantages over traditional endophotocoagulators of being much smaller, less costly, and requiring no water cooling, without sacrificing power output or ease of delivery.