Laser Peripheral Iridotomy, or LPI, is a procedure used to lower eye pressure in patients who either have angle closure glaucoma or are at risk of angle closure. Using a YAG laser, your Doctor will focus the laser at the top of the iris. The laser creates an opening in the iris. The opening allows aqueous fluid to drain out of the eye and therefore lower eye pressure. In approximately one third of cases the opening may close, in these cases, retreatment will be required. A small amount of bleeding from the iris is quite common and usually stops in less than a minute.