Retinal damage after argon laser iridotomy

We conducted a prospective clinical study to evaluate potential retinal damage after argon laser iridotomy in 25 eyes of 22 patients with primary chronic angle-closure glaucoma. Kinetic perimetry and ophthalmoscopy showed no detectable damage. Iridotomy required a mean of 11.4 +/- 10 joules to achieve a patent coloboma of 200 micron after one to three sessions. Dark-prone and mydriasis tests were performed one month after surgery. Pilocarpine was discontinued in all cases. Both static perimetry and fluorescein angiography of the midperiphery corresponding to the meridian of laser coloboma done six months after surgery showed focal damage. There was no damage in control tests of the same eyes in an opposite area of the retina.