A 13-YEAR-OLD GIRL had been bothered for several years by increasing episodes of transitory “blindness” in her right eye. These usually occurred outdoors under bright, sunny conditions. One year earlier, she had been diagnosed as having iris cysts. Therapy with the mydriatics 1% tropicamide and 2.5% phenylephrine hydrochloride achieved no perceptible effect. She had no other history of use of ocular medications. On examination, her bestcorrected visual acuity was 20/25 OD and 20/20 OS. With bright light, the vision in her right eye decreased to less than 20/400. Slitlamp examination showed multiple, dark-brown iris pigment epithelial cysts along the pupillary margin of the right eye, with the visual axis open when the pupil was not fully constricted (Figure 1). Obstruction of the visual axis by the cysts was easily demonstrated by using brighter illumination (Figure 2). Argon laser photocoagulation of the 2 larger cysts was performed with topical anesthesia. A drop of 0.15% brimonidine tartrate was instilled before and after treatment. Fifty burns, each of 500-mW power, 200millisecond duration, and 50micrometer spot size, were used to rupture and then shrink the cysts’ walls (Figure3). No postlaser complications occurred, including elevation of intraocular pressure or excessive inflammation. At 9 months’ follow-up, the patient reported no further episodes of visual disturbance.