Laser Iridotomy

This video is created by Advanced EyeCare of New York and is available on Youtube

What is an Iridotomy?

Laser iridotomies are carried out to treat or prevent an attack of angle closure glaucoma. If you are scheduled to have this procedure, you either have an attack of acute glaucoma,  are at risk for such an attack or have chronic angle closure. Iridotomy refers to a hole made in the iris of the eye. The iris is the coloured part of the eye, and is located behind the cornea. This procedure is done with a laser beam. Your procedure will be done with a Neodynium:Yag laser.


In the majority of individuals this treatment will successfully prevent or treat an attack of acute glaucoma. A longstanding attack may not respond to iridotomy and may require surgery in an operating room.


The procedure takes only a few minutes but you will be in the office for around two hours as you require drops prior to the procedure and an eye pressure check after the procedure.

How is this procedure done?

  • You will be given numbing eye drops.

  • You will be positioned comfortably at the laser. The laser machine looks similar to the examination microscope your doctor uses to examine your eyes at each visit. The laser itself makes some noise and flashes a light as bright as the flash on a camera.

  • A band will be placed behind your head as a gentle reminder to keep you from moving backwards during the procedure.

  • The doctor will place a lens on the surface of the eye to be lasered. You are able to blink gently.

  • The doctor will position a green light in front of the other eye and you will be asked to look at that light throughout the procedure.

  • The doctor will spend a few moments trying to find the best spot to do the procedure.

  • A test shot with no power will fired so that you can accustom yourself to the sound made by the laser.

  • The laser will then be used to open the hole in the iris. You may feel a little pressure or small ’pop’ during the laser and some people find the laser shots painful.

  • Following the procedure, you will receive more pressure lowering drops and anti-inflammatory drops.

  • You will be asked to wait 45 minutes after your procedure for a pressure check. You will receive a prescription for your post op drops at this time and if you wish, you can use the time to purchase your drops at the pharmacy.

Risks of Laser Iridotomy:

Like any surgery, laser iridotomy carries risks.

Fortunately, problems or complications are uncommon. Risks include:

  • Headache or brow pain:
    Pilocarpine eye drops are used to constrict the pupil before this procedure. These drops can cause a headache or brow pain. If you are in pain, please ask a member of our staff for Tylenol.

  • A sudden increase in eye pressure:
    Alphagan eye drops are used before the procedure to prevent a pressure rise. If your pressure does rise you will be sent home with pressure lowering eye drops or pills.

  • Eye redness, swelling or pain:
    Topical steroid eye drops are used for several days following the procedure.

  • Bleeding in the eye:
    If possible, avoid blood thinning medications for one week prior to your laser. Remember that Aspirin and Advil are blood thinners. Talk to your doctor if you are on Warfarin (Coumadin), Eliquis, Pradaxa or Xarelto.

  • Blurry vision:
    You may be blurry for 24 hours.


  • Line of light (linear dysphotopsia):
    A small number of patients complain about a line of light that they see following this procedure in certain lighting conditions.  This has been reported from 1% to 4% in different studies. Of these patients, most will adapt quickly and ignore these lines. However some patients have trouble adapting.

  • Cataract (clouding of the eye’s naturally clear lens):
    It is possible that this procedure is associated with cataract progression. There are studies that support this and others that do not.

  • The need to have laser iridotomy again:
    Sometimes an iridotomy can close. It can be reopened with a repeat laser procedure. This happens more commonly in brown eyes.

Laser Iridotomy FAQ

  • Why do I put in drops at home before the procedure?
    Pilocarpine drops are given to shrink the pupil prior to laser iridotomy. The procedure is much easier to do if the pupil is small and it can take a long time for the eye drops to work, especially if your eyes are dark brown. To ensure the best possible pupil constriction, you will be given a small container (minim) of Pilocarpine eye drops and asked to instill a drop to the eye(s) scheduled for laser both two hours and then one hour before your scheduled appointment. If you are of Asian or African Canadian background, you may also be asked to instill a drop at bedtime the night before your treatment. Don’t worry if you feel you didn’t get your drops in correctly. If your pupil(s) is not adequately constricted, we will give you another drop in the office.

  • Is there a difference between blue eyes and brown eyes?
    Dark brown eyes can be more difficult to laser. When the laser touches the iris a cloud of pigment is released. The darker an eye, the more pigment is released. If your doctor’s view is clouded by pigment, you will be asked to wait in the waiting room, giving the pigment time to clear, and then brought back into the laser room to complete the procedure. Rarely, there is so much pigment that the procedure cannot be finished in a single visit and a second visit is scheduled to complete the iridotomy.

  • Does the laser hurt?
    Most people hardly feel this procedure. For some people the laser pulse can be painful. Each pulse lasts a fraction of a second. The number of pulses used is variable.

  • How long will I be in the office?
    On average you will be in the office for 90 minutes to 2 hours. Your pre-op eye drops must take effect and your pressure needs to be checked 45 minutes after your procedure.

  • Can I drive to the procedure?
    It is best not to drive yourself to this procedure.

  • I am very nervous. Is it possible for me take something to help me stay calm during this procedure?
    If you are extremely anxious, we can give you a prescription for Ativan to use prior to the procedure.

  • Do I need any medicine after this?
    You will be given a prescription for an anti inflammatory steroid eye drop.

  • What kind of follow up do I need?
    You will be seen one week following the procedure at our office. Before leaving the office on the day of the surgery, book a follow up appointment to see Dr. Goldberg/ Dr. Hinton. You will need to be seen again six months following the procedure by your doctor.

  • Is this procedure covered by OHIP?
    Yes, laser iridotomy is covered by OHIP.

  • Can I stop my glaucoma eye drops?
    If you are on glaucoma medication you must continue to use your eye drops as directed

  • Can I have both eyes lasered on the same appointment?
    In general, each eye is done at a separate appointment, but if you prefer, both eyes may be done at the same time.