Different types of retinal lasers
Lasers are one of the most important tools that retinal specialists have. These lasers are very different from the types that are used in refractive surgery or glaucoma surgery. These lasers are usually performed right in the office.
Panretinal Photocoagulation (PRP)– In certain eye conditions such as diabetic retinopathy or vein occlusions, the usual flow of blood and nutrients to the retina can become compromised (ischemic). The eye will sometimes try to resupply the retina by growing new abnormal blood vessels (neovascularization). However, these blood vessels do not behave normally, and have a tendency to bleed and lead to the formation of scar tissue and retinal detachments. When neovascularization develops, your doctor will perform panretinal photocoagulation to get rid of these bad vessels. The laser is usually applied over several sessions.
Focal or Grid Macular Laser- Macular edema or swelling can develop in various eye conditions. When this occurs, the central vision becomes blurred. This type of laser treatment is designed to minimize worsening of the edema, and can sometimes reduce the swelling. The goal of the laser treatment is to prevent worsening of vision. Sometimes, vision may improve as the swelling improves.
Laser Retinopexy- When a hole or tear develops in the eye, it often needs to be sealed off to prevent it from getting larger and turning into a retinal detachment. The laser is applied to surround the retinal break. The laser acts like a glue to seal the edges of the break down. However, like glue, it takes up to 1-2 weeks for it to “harden”. During this time, your physician may place restrictions on your activity until the laser has had adequate time to seal the break.
Thermal Laser for Choroidal Neovascularization- In certain eye conditions such as wet macular degeneration, abnormal blood vessels can begin to grow under the retina (choroidal neovascularization). Laser treatment can be applied to destroy the choroidal neovascularization. This is a “hot” thermal laser that not only destroys the underlying bad blood vessel, but also the overlying retina. Therefore, care must be taken to avoid applying the laser too close to the center of the vision. Otherwise, the patient will notice a blind spot in the center of their vision. Other treatments exist for patients where the blood vessels have invaded the center of the vision and thermal laser is not a good option.
Photodynamic therapy for Choroidal Neovascularization- This is a “cold” laser that is sometimes used for the treatment of choroidal neovascularization that has involved the center of one’s vision. A special dye (Visudyne) is first injected into one’s arm vein and allowed to travel up into the eyes where the medicine is selectively taken up by the bad blood vessels. A “cold” laser is then applied to the area of the bad blood vessels to activate the medicine which in results in closure of the choroidal neovascularization. Because this is a non-thermal laser, the collateral damage to the overlying retina is minimized. Because light activates this medicine, patients receiving this treatment are advised to stay out of the sunlight or 5 days following treatment.