Laser Treatment for Diabetic Retinopathy: PRP and Focal Laser

Laser treatment has been a cornerstone of diabetic eye care for decades, helping to preserve vision in patients with diabetic retinopathy and diabetic macular edema. According to a CDC study of Medicare patients published in JAMA Ophthalmology in 2022, the use of laser photocoagulation for diabetic macular edema decreased from 46 percent to 13 percent between 2009 and 2018 as anti-VEGF injections became the preferred first-line treatment (CDC, 2022). However, laser therapy remains an important tool that works alongside newer treatments. At Greenwich Ophthalmology Associates, our diabetic eye care specialist uses proven laser techniques alongside the latest medical therapies to protect the sight of patients living with diabetes.

Panretinal photocoagulation, commonly called PRP, is used to treat proliferative diabetic retinopathy (PDR), the most advanced stage of the disease. In PDR, oxygen-starved areas of the retina trigger the growth of fragile, abnormal new blood vessels, a process called neovascularization. These vessels can bleed into the vitreous cavity or pull on the retina, potentially leading to severe vision loss or retinal detachment. PRP works by applying hundreds to thousands of small laser burns to the peripheral retina, reducing the retina's oxygen demand and signaling the body to slow or stop the growth of these dangerous vessels.

Focal laser treatment targets specific leaking blood vessels, called microaneurysms, that cause fluid to accumulate in or near the macula. This fluid buildup is known as diabetic macular edema (DME). Grid laser applies a pattern of gentle burns over a broader area of macular swelling when the leakage is more diffuse. Both approaches aim to seal off leaking vessels and reduce retinal thickening so central vision can stabilize or improve.

Your diabetic eye care specialist will choose the appropriate laser strategy based on the stage of your diabetic retinopathy and whether macular edema is present. PRP is typically indicated when proliferative changes are detected, while focal or grid laser is considered for clinically significant macular edema. In some cases, both types of laser treatment may be needed during the same course of care.

Retinal laser therapy is considered safe and well-established, but like any medical procedure, it carries some potential side effects. Because PRP treats the peripheral retina, some degree of peripheral (side) vision reduction is expected. Patients may also experience mild decreases in night vision and color perception. These changes occur because the laser intentionally reduces function in the outer retinal areas to protect the critical central vision. Most patients find that these side effects are manageable and far preferable to the vision-threatening complications of untreated proliferative retinopathy.

Focal laser treatment carries a lower risk of noticeable side effects since it targets a smaller area. Some patients may notice small blind spots (scotomas) near their central vision if the laser is applied close to the fovea. Temporary increases in macular swelling can occur in the first few days after treatment but typically resolve as the therapeutic effect takes hold.

Uncommon risks include accidental laser burns to the fovea, choroidal neovascularization at treatment scars, or worsening of macular edema. Serious complications are rare when treatment is performed by an experienced diabetic eye care specialist using modern laser systems with precise targeting capabilities. Our team carefully plans each session using advanced retinal imaging to minimize these risks.