Update on SLT Laser Treatment
Selective Laser Trabeculoplasty (SLT) is a safe, effective laser treatment to lower eye pressure in patients with open-angle glaucoma or ocular hypertension.
As an ophthalmologist, I often describe SLT as a way to help your eye’s natural drainage system work better—without incisions and often without the need for daily drops.
Inside the eye, fluid drains through a structure called the trabecular meshwork. In glaucoma, this drainage system becomes less efficient, raising eye pressure and risking optic nerve damage. SLT uses gentle, targeted laser energy to stimulate the trabecular meshwork, improving the outflow of fluid from inside the eye, and lowering eye pressure.
A landmark clinical trial, the LiGHT Study (Laser in Glaucoma and Ocular Hypertension), significantly changed how we approach initial glaucoma treatment. This large, randomized study compared SLT as first-line therapy to starting with medicated eye drops. The results showed that SLT was at least as effective as drops in controlling eye pressure, with many patients remaining drop-free for years. It was also found to be cost-effective and associated with excellent safety outcomes. Because of this evidence, many eye doctors now offer SLT as a primary (first-line) treatment rather than reserving it for later stages.
The procedure is performed in the office and typically takes about 5–10 minutes. After numbing drops are placed, a special lens is used to focus the laser on the drainage system. Most patients feel little to no discomfort. There are no incisions, and you can usually resume normal activities the same day.
More recently, technology has advanced further with Direct Selective Laser Trabeculoplasty (DSLT). DSLT delivers laser treatment externally, without placing a contact lens on the eye, and uses automated targeting of the drainage system. Since this is a new technology, we do not know about its long-term efficacy. While DSLT is still being incorporated into clinical practice, it represents an exciting step toward faster, more comfortable, and potentially more accessible glaucoma care.
Today, it is increasingly common for eye doctors to recommend SLT early in the disease process. The procedure is performed in the office, takes only minutes, and has minimal downtime. The pressure-lowering effect may last several years and can be repeated if needed.
For patients and caregivers, it is important to remember that glaucoma requires lifelong monitoring. SLT is not a cure, but it is a powerful, evidence-based tool that helps us preserve vision safely and effectively over time.
Posted on April 6, 2026. Article by Sahar Bedrood MD, PhD.
Sahar Bedrood, MD, PhD
Dr. Sahar Bedrood is a board-certified and fellowship-trained ophthalmologist in Los Angeles, California with a focus in glaucoma and advanced cataract surgery. She has an MD/PhD from Keck School of Medicine of the University of Southern California, an undergraduate degree from UCLA and surgical fellowship training from John’s Hopkins University.