Glaucoma is a group of eye conditions that damage the optic nerve, often due to elevated intraocular pressure (IOP). This pressure builds up when the eye’s natural fluid, aqueous humor, cannot drain properly. Laser treatment offers a non-invasive approach to managing this condition by improving fluid outflow or reducing fluid production. It is an outpatient procedure that uses a focused beam of light energy to make microscopic changes to the eye’s drainage system. The goal is to lower the IOP, protecting the optic nerve from further damage and preserving vision.
Indications for Laser Therapy
A physician may recommend laser treatment for glaucoma management when eye drops alone are insufficient to control the intraocular pressure. This option is often considered when a patient’s glaucoma is progressing despite adherence to a medication regimen.
Laser procedures are also beneficial for individuals who experience negative side effects from glaucoma eye drops or who have difficulty adhering to a daily drop schedule. For some types of open-angle glaucoma, a laser procedure may even be offered as a first-line treatment instead of starting with daily medications. The procedure provides an alternative way to achieve the target pressure, reducing the dependency on or supplementing the effectiveness of topical medications.
Different Types of Glaucoma Laser Procedures
The specific type of laser procedure used depends entirely on the type of glaucoma a patient has and the underlying mechanism causing the elevated pressure. The most common laser treatment for open-angle glaucoma is Selective Laser Trabeculoplasty, or SLT. This procedure uses a low-energy laser to target specific pigmented cells in the trabecular meshwork, which is the eye’s drainage tissue located at the junction of the iris and cornea. The treatment stimulates a biological response in the area, encouraging the body to clean and remodel the drainage channels, thereby enhancing the outflow of aqueous humor.
SLT uses very short pulses of light that selectively treat pigmented cells without causing thermal damage or scarring to the surrounding tissue. This non-destructive nature is an advantage, as it often allows the procedure to be safely repeated if the pressure begins to rise again over time. In contrast, Argon Laser Trabeculoplasty (ALT) is an older technique that uses a thermal laser causing coagulative damage, limiting its repeatability.
For patients diagnosed with angle-closure glaucoma, or those at risk due to narrow drainage angles, the treatment is typically a Laser Peripheral Iridotomy, or LPI. This procedure uses a high-energy laser to create a tiny, precise opening in the peripheral edge of the iris. The hole allows the aqueous humor to flow more freely between the back and front chambers of the eye, equalizing pressure and preventing the iris from blocking the main drainage angle.
A fourth type of procedure, Cyclophotocoagulation (CPC), is generally reserved for more advanced or refractory cases of glaucoma. CPC uses a laser to target the ciliary body, the part of the eye responsible for producing the aqueous humor. By partially destroying these cells, the treatment reduces the overall amount of fluid produced, thereby lowering the intraocular pressure.
The Patient Experience: Before, During, and After Treatment
Preparation for a laser procedure is relatively straightforward and begins with the application of numbing eye drops to ensure comfort throughout the process. In some cases, a physician may also administer a pressure-lowering drop before the procedure to minimize the chance of a temporary pressure spike immediately following the laser application. Patients are typically advised to arrange for someone to drive them home afterward, as vision may be temporarily blurry.
The procedure is performed in an outpatient setting, often using a device similar to the slit lamp microscope used for a routine eye examination. After the eye is anesthetized, a special contact lens is placed on the eye’s surface to help focus the laser beam onto the target tissue. Patients are awake during the short treatment, which usually takes only five to fifteen minutes per eye.
During the application of the laser energy, patients may see brief, bright flashes of light but generally report feeling little to no pain. Following the procedure, it is common to experience temporary side effects such as mild eye irritation, redness, or slightly blurred vision, which usually resolve within a few hours or days. The doctor will provide anti-inflammatory drops to use for a short period and will check the intraocular pressure shortly after the treatment to confirm stability.
Expected Results and Follow-Up Care
The full effect of the laser treatment on intraocular pressure is not always immediate and can take several weeks or even a few months to fully manifest. Success rates for procedures like SLT are often high initially, with many patients achieving a pressure reduction, sometimes in the range of 20 to 30 percent. For 70 to 85 percent of patients, SLT is successful in lowering eye pressure, though this may not eliminate the need for all glaucoma medications.
It is important to understand that laser treatment is a method of managing glaucoma, not a permanent cure for the disease. The pressure-lowering effect of procedures like SLT and ALT can diminish over time, often lasting for an average of three to five years before potentially requiring retreatment or a change in therapy.
Long-term care involves regular follow-up appointments to monitor the eye pressure and the health of the optic nerve. These check-ups are necessary to ensure the pressure remains at a safe level for vision preservation and to detect any signs of the treatment effect wearing off. If the laser treatment becomes less effective, the physician may recommend adjusting medication, repeating the laser procedure, or considering traditional incisional glaucoma surgery.