A laser peripheral iridotomy is required to treat narrow angles or angle closure glaucoma. This condition is more common in Asians. Other risk factors include female gender and age more than 60 years.
A small opening is made within the iris (the colored part of the eye) using a laser. The opening in the iris allows fluid to flow from behind the iris through the opening, enabling the iris to fall back into a more normal position and widening the drainage angle.
The laser is performed to prevent an acute attack of angle-closure glaucoma which is marked by very high eye pressure because of complete blockage of the drainage channel in the eye. Symptoms include severe eye pain, headache, red eye, blurred vision and seeing haloes around lights. This condition is dangerous because it can cause blindness in a few days if not properly treated.