Is There a Laser Treatment For Glaucoma?
Yes, there is a laser treatment for glaucoma. There are different types of laser treatments for glaucoma depending on the type and severity of glaucoma. Glaucoma is progressive, irreversible visual impairment due to increased intraocular pressure leading to irreversible optic nerve damage. Glaucoma is mainly of two types: open angle glaucoma and angle closure glaucoma. If it is left untreated then it can lead to permanent blindness.
In LASER (Light Amplification by Stimulated Emission of Radiation), a focused light beam with low heat absorption is passed through the cornea to the trabecular meshwork to help drain better and reduce the intraocular pressure. Laser treatment helps in lowering intraocular pressure in majority of the patients, but some patients do not respond to it. A successful laser treatment generally lasts for 1 to 5 years and a repeat laser or conventional surgery might be needed after that.
Laser trabeculoplasty is usually performed in patients with open angle glaucoma after a trial of eye drops and medications or using multiple eye drops, which fails to reduce the intraocular pressure. This is a relatively simple, quick, safe and painless procedure and is completed in less than 30 minutes in eye doctor’s office/clinic. Generally, two sessions, weeks or months apart, are required for laser trabeculoplasty, but unfortunately, the treatment lasts only about 2 years, after which the trabecular meshwork drainage system starts to clog again leading to increase in intraocular pressure again. There are basically two types of laser trabeculoplasty that include argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT).
- Argon Laser Trabeculoplasty (ALT): The laser beams help in opening/declogging the drainage system releasing the pressure inside the eye/eyes. In general, only half of the fluid channels are treated in the first session and if necessary then other half can be treated in the second session. This helps prevent increased pressure post-surgery. Generally, ALT is not repeated after the second session due to scar tissue formation. The success rate of ALT is about 75 % in reducing the IOP.
- Selective Laser Trabeculoplasty (SLT): It is usually attempted after an unsuccessful attempt with ALT. In SLT low-level laser is used to target only selective areas of the trabecular meshwork with increased pressure, therefore it can be repeated several times without causing any scar tissue formation at the angle. If SLT also fails to reduce the IOP then finally incisional surgery is opted.
Laser Peripheral Iridotomy (LPI): This is mostly used for angle closure glaucoma, which occurs when the angle between the iris (colored portion) and cornea (clear outer layer) becomes narrower due to bulging of iris. This narrowed angle causes incomplete drainage of aqueous humor leading to increased intraocular pressure. LPI is used to relieve pressure by creating a small hole in the iris, thus leading to normal fluid drainage.
Laser Cyclophotocoagulation: This is also known as ciliary body destruction or laser cycloablation. Laser cyclophotocoagulation is used as an alternative to incisional surgery or if other laser techniques or eye drops have been proved ineffective at lowering the intraocular pressure. This laser treatment is usually reserved for severe/advanced glaucoma patients who have severe vision loss. Laser cyclophotocoagulation is used to destroy ciliary bodies that produce aqueous humor, thus less aqueous humor will be formed, which will lead to decreased intraocular pressure. Laser cycloablation needs to be repeated several times to keep glaucoma under control.
Cyclocryopexy is another technique that aims at decreasing aqueous humor production by using freezing method rather than laser technique.
Side Effects of Laser Treatment for Glaucoma
Generally, a patient can resume his daily activity immediately the next day after laser treatment, but he may experience certain side effects. The side effects of laser surgery are usually mild that range from slight discomfort, irritation, stinging sensation, blurry vision to temporary increase/decrease in intraocular pressure post-surgery.
Generally, eye drops are still required after laser treatment for glaucoma and intraocular pressure maintenance, but fewer amounts of the eye drops are required.