A comparison of laser-induced retinal damage from infrared wavelengths to that from visible wavelengths

Corneal, lenticular, and retinal damage have been observed following exposures to a laser emitting in the near-infrared wavelength range (Nd:YAG, 1.318 μm). Ocular damage thresholds are much higher than for visible wavelengths. However, it was found that infrared (IR) exposures may result in multiple damage sites throughout the ocular medium and retina; that exposure sites which initially appear to be unaffected may reveal slowly developing (days or longer) degeneration; and that late inflammatory responses may ultimately spread to areas of tissue not directly irradiated by the laser. The nature of tissue degeneration following IR laser exposure is examined and compared to that following visible wavelength laser exposures using three approaches: histopathology, scanning laser ophthalmoscopy, and optical coherence tomography. Each approach is shown to reveal unique aspects of the IR laser-tissue interaction when contrasted with effects induced by visible wavelengths.