Argon laser trabeculoplasty (ALT) is a laser surgical procedure used for patients with open-angle glaucoma to help lower intraocular pressure (IOP). ALT is used to treat the trabecular meshwork—the mesh-like drainage canals surrounding the iris—that serves as the eye’s drainage system. The goal of treatment with ALT is to improve the flow of fluid out of the eye, helping to lower IOP.

ALT is typically performed in the ophthalmologist’s (Eye M.D.’s) office or an outpatient surgery center. The procedure usually takes about five to ten minutes. First, anesthetic drops are placed in your eye. The laser device looks similar to the examination microscope that your ophthalmologist uses to look at your eyes at each office visit.

You will experience a flash of light with each laser application. Most people are comfortable and do not experience any significant pain during the surgery, though some may feel a little pressure in their eye during the laser procedure.

Most patients will need to have their pressure checked after the laser treatment, since there is a risk of increased eye pressure after the procedure. If this does occur, you may require medications to lower the pressure, which will be administered in the office. Rarely, IOP elevates to a very high pressure and does not come down. If this happens, you may need to have surgery to lower the pressure.

Most people notice some blurring of their vision after the laser treatment. This typically clears within a few hours. The chance of your vision becoming permanently affected from this procedure is very small.

In general, patients can resume normal daily activities the day after laser surgery. You may need to use drops after the laser surgery to help the eye heal properly.

Risks associated with ALT include

• increased pressure in the eye, possibly requiring medication or surgery to lower it;

• inflammation in the eye;

• bleeding;

• damage to the cornea, iris, or retina from the laser light;

• failure to adequately lower the eye pressure; and

• need for repeat laser surgery.

It will take several weeks to determine how much your pressure will be lowered with ALT. You may require additional laser or glaucoma drainage surgery to lower the IOP if it is not sufficiently lowered after the first laser treatment.

In most cases, medications are still necessary to control and maintain eye pressure. However, surgery may lessen the amount of medication you need.