Is Laser Peripheral Iridotomy Painful?

Peripheral iridotomy is done to treat the raised eye pressure in the ‘Angle-closure glaucoma’.

The ‘angle’ is the space between the iris (colored part of the eye) and the cornea (transparent layer covering the iris). This ‘angle’ is important because it contains the drainage channels for the eye fluid. Any narrowing of this ‘angle’ can cause these drainage channels (trabecular meshwork) to clog, causing raised eye pressure. Raise eye pressure (glaucoma) is dangerous for the optic nerve and can lead to blindness.

The peripheral laser iridotomy is an extra opening created surgically over the iris. It creates an additional draining channel and thus relieves the raised eye pressure.

The procedure takes around ten minutes in the outpatient setting. The doctor will explain the procedure to you and put eye drops in the eye to make the pupil small and the iris tense. 30 minutes after the drops are put into the eye, the doctor will make you sit near the Laser machine. 

He will place a contact lens over your eye. The lens absorbs the heat emitting from the laser during the procedure and protects the cornea from burns.

The doctor will shoot the laser at the iris to make a small hole over it. The hole is made at a 3-o-clock or a 9-o-clock position in the iris nearer to its outer margin. The hole must be about 1.5-2 millimeters in size to provide adequate drainage for the eye fluid. Sometimes multiple iridotomies may be required to make ensure adequate fluid drainage.

After the procedure, there may be temporary increased ocular pressure due to the clogging of the drainage system by the iris particles. It is therefore important that the person is made to wait in the clinic and the eye pressure is measured at 30 minutes, one hour, and two hours after the procedure.

If the eye pressure is more than 30 mm Hg, or if it has increased by 8 mm Hg compared to the pre-operative value, the person is to be monitored for glaucoma and anti-glaucoma drops are prescribed.

You can go home the same day after the procedure. However, you are not allowed to drive. So, make sure you bring someone to take you home.

The eye drops used during the procedure may cause blurry vision lasting for the day. You may have a foreign body sensation in the eye for a few days after the surgery. Other problems might be glares (inability to look at bright lights) and halos (bright circles that surround a light source, like headlights). These are temporary problems and go away on their own. People on blood thinners or warfarin are at a high risk of bleeding during the procedure.

 Your doctor will give you eye drops for the reduction of your eye pressure and redness. You must use the drops as directed by your doctor. Make sure you wash your hands before touching the drops or the eye. The doctor will schedule follow-up visits a week after and later in the fourth or the sixth week. During the first visit, he will look for the patency of the hole and measure the eye pressure. He will also measure the ‘angle’ with a test called gonioscopy.

At the next follow-ups, the doctor will check your eye pressure again. He will decide if you need to continue the eye pressure drops for a longer time. You may need to wear an eye patch for about six weeks to minimize the discomfort. 

In some cases, a repeat procedure may be needed if the first iridotomy fails or is inadequate.