The “angle” that is being referred to is the angle between the iris, which makes up the colored part of your eye, and the cornea, which is the clear window front part of your eye. Narrow angles limit the outflow of fluid from the eye causing it to back up, which increases pressure in the eye. The elevated eye pressure can damage the optic nerve.
Laser iridotomy is a procedure to treat narrow angles, chronic angle-closure glaucoma, and acute angle-closure glaucoma. The impact of an acute-angle closure glaucoma attack is profound and irreversible, and the condition must be treated immediately.
During a laser iridotomy, the laser light is used to create a small hole in the iris that forms your pupil, which allows drainage of intraocular fluid. Before the laser was invented, this small hole was created using scissors in the operating room. Being able to do the procedure in the clinic office using a laser is a safer and big advancement.
Video: Laser Iridotomy
The Procedure is Nearly Painless
Many people are concerned about possible pain and side effects of laser iridotomy. Generally speaking, the procedure is nearly painless. Your eye is anesthetized with numbing eye drops, and a small lens is placed on the surface of the eye to help focus the laser.
During the actual laser procedure itself, you may feel a sensation that something happened or a pinprick sensation, or you may feel nothing at all. The laser usually makes a noise when fired, which can be somewhat startling.
The procedure is fairly short, so if pain is a potential side effect, it is short-lived. After the laser iridotomy is completed, the eye may be a little red, light sensitive, and uncomfortable for the first 24-72 hours after the procedure.
Elevated Eye Pressure
Another side effect is eye pressure elevation. This is also a short-lived side effect that occurs soon after the iridotomy is performed. This side effect occurs because iris pigment is released when the hole is created with the laser. The pigment can temporarily clog the drainage system, and cause the eye pressure to increase. For this reason, you will be asked to wait 30-60 minutes after the procedure so that your eye pressure can be rechecked. If the eye pressure is abnormally elevated, you will be given topical eye drops to lower the eye pressure, which is then rechecked after another 30-60 minutes.
Vision will also be temporarily blurry after the laser iridotomy procedure. This is partly because some gel is used with the special lens, and even if it is rinsed out at the end of the procedure, the vision is still a little blurry. Vision is also sometimes affected by the pigment release or inflammatory response when the hole is created. This is also temporary, and you may be asked to use anti-inflammatory eye drops for a week after the procedure. Finally, in preparation for the procedure you will be given an eye drop that makes the pupil smaller and thins the iris tissue. This eye drop can blur your vision, as well as give you a brow ache or headache. Given all of this, it is probably wise to have someone drive you home after the procedure and take it easy the rest of the day.
Other Potential Short-Term Issues
Other short-lived, typically reversible side effects include bleeding at the site of the hole, swelling of the cornea, and persistent inflammation. Many ophthalmologists will prescribe a short course of anti-inflammatory eye drops for the latter reason.
It is also possible, although uncommon, for the hole to close up and a retreatment procedure may be needed. People of African or Asian descent tend to have thicker irises, and these eyes require more laser energy, sometimes two different types of laser, or several sessions to create a hole of the right size.
Longer-Lasting Glare or Halos
One potential side effect that could be longer lasting is glare or halos (“ghost images”). If you imagine the eye is like a camera, with images being projected onto the retina (like the film of a camera), the pupil acts as the aperture, allowing light to come through. With laser iridotomy, a second small hole is created, thereby allowing another hole through which light can pass. There is a risk of stray light reaching the retina and causing symptoms such as glare or ghost images. This is quite rare, and if it does happen the brain usually will learn to adapt or ignore it over time.
Finally, many ophthalmologists have switched from positioning the hole at the 11 to 1 o’clock position (where it was thought that eyelid coverage would prevent light from passing through and causing symptoms) to the 3 or 9 o’clock positions. The latter has been shown to prevent the ghost images side effect, although given how rare this side effect is some ophthalmologists may still create the hole at the 12 o’clock position, especially if the eyelid provides complete coverage.
Most people do well after laser iridotomy and do not experience significant side effects, but it is always helpful to talk with your ophthalmologist so that you can fully understand the procedure and the expected results.
- Glaucoma Toolkit (Information to Help You Understand and Manage Glaucoma)
- Expert Information on Glaucoma (Articles)
- National Glaucoma Research Report (Newsletters)
- What are Narrow Angles? (Video)
- Peripheral Iridotomy: A Laser Procedure for Narrow Angles (Article)
- Primary Angle-Closure Glaucoma (Article)
- Glaucoma: Treatment Options (Publication)
- Glaucoma: Essential Facts (Publication)
This content was last updated on: October 15, 2018
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