There are two main types of laser surgery to treat glaucoma. They help aqueous humor, the fluid inside the eye, drain from the eye. These procedures are usually done in the ophthalmologist’s office or an outpatient surgery center.
Selective Laser Trabeculoplasty (SLT) reduces eye pressure in people with open-angle glaucoma. In certain cases, SLT can reduce eye pressure enough such that eye drops are not needed. In other cases, SLT is used in conjunction with eye drops.
SLT selectively targets pigmented cells in the drainage passage (trabecular meshwork) of the eye to stimulate an increase in fluid drainage. SLT replaces an older procedure known as argon laser trabeculoplasty (ALT). The main advantages of SLT over ALT include:
However, many people will continue to need medication after laser treatment to keep the eye pressure low enough to prevent further damage to the optic nerve. The results of the SLT tend to decrease over time, but this procedure can be repeated, often with excellent results. In certain people with advanced glaucoma for whom SLT does not sufficiently reduce eye pressure, glaucoma surgery may be necessary.
SLT is usually done as an outpatient procedure under topical anesthesia. Eye drops are put in the person’s eye before the procedure to prevent a transient rise in eye pressure. Some people feel a sensation of heat in the eye during the SLT. However, there is usually no pain. The entire procedure usually takes place in less than 10 minutes. Typical follow-up with the doctor occurs approximately 2 weeks after the procedure.
Complications of SLT are rare. The most common complication of SLT is a transient increase in the eye pressure of the treated eye. An eye pressure test may be performed within the hour after the procedure in order to monitor for this.
Other complications of laser treatment may include, but are not limited to, a brief period of inflammation of the iris, the colored part of the eye, pain (rare), and transient blurred vision (rare).
Laser iridotomy is used to:
Laser iridotomy uses a very focused beam of light to create a tiny drainage hole in the iris, the colored part of the eye. This opening allows aqueous humor, the fluid inside the eye, to flow between the anterior chamber, the front part of the eye, and the area behind the iris, the posterior chamber. This opening may decrease pressure in the eye and helps to prevent sudden closed-angle glaucoma.
In people with an attack of sudden closed-angle glaucoma, laser iridotomy is usually successful but if scar tissue has developed in the drainage angle, high eye pressure may persist. In this situation, additional treatment, such as eye drops or surgery may be necessary to lower the pressure.
In people who have had an attack of sudden closed-angle glaucoma in one eye, laser iridotomy in the other eye will prevent a similar attack in that eye. Without treatment, there is a 50% chance that sudden closed-angle glaucoma will also develop in the unaffected eye.
Laser iridotomy is extremely successful in preventing sudden closed-angle glaucoma in people who are at risk as a result of narrow drainage angles. Over time, the new drainage hole can become blocked. If this occurs, a repeat iridotomy is needed and is usually successful.
Laser iridotomy is usually done as an outpatient procedure under topical anesthesia. Some people feel a sensation of heat in the eye during the procedure. The entire procedure usually takes place in less than 10 minutes. There is usually no pain after laser iridotomy. Typical follow-up with the doctor occurs approximately 1 week after the procedure.
Complications of laser iridotomy may include, but are not limited to, brief blurred vision (common), transient increased in eye pressure, and bleeding (rare). In a small percentage of patients the new drainage hole may close but can easily be reopened.