Simulated argon laser iridotomy was performed in 12 cynomolgus monkey eyes to evaluate the effectiveness of the Abraham iridectomy lens in preventing inadvertent retinal burns. At 600 milliwatts, only two of the three eyes developed small retinal burns using the Abraham lens, whereas three eyes developed larger retinal burns without the Abraham lens. At 1000 milliwatts, retinal burns occurred with or without the Abraham lens, but the size and intensity of the burns were reduced with the lens.