This stands for panretinal photocoagulation, and is a laser treatment commonly used for diabetic retinopathy. With diabetes, blood vessels become leaky and the retinal tissue in the eye can become hungry for oxygen because of poor blood delivery. The oxygen-starved retina cells respond by producing protective hormones called VEGF (vascular endothelial growth factor). VEGF causes the formation of new blood vessels, which at first glance ought to be a good idea … after all, new blood vessels might help feed the hungry retina! Unfortunately, the new blood vessels are abnormal and tend to scar, contract, and bleed easily. This can lead to retinal detachments and vitreous hemorrhage. The abnormal blood vessels can even grow into the trabecular meshwork (the “drain” of the eye) similar to tree roots growing into a house’s plumbing. This can lead to acute glaucoma with severe vision loss. This abnormal vessel growth is called neovascularization and it needs to be treated before it gets out of hand. To treat neovascularization, a PRP laser procedure is performed. With this procedure, hundreds (sometimes thousands) of laser spots are burned into the peripheral retina, essentially destroying the peripheral retinal cells. By sacrificing the hungry peripheral retina (where most of the oxygen deprivation is occurring) less VEGF is produced and the neovascularization will stop and even regress. While it may seem barbaric to sacrifice part of the retina in this fashion, the procedure is very important as it saves the more important central vision. Few people notice visual changes after the PRP procedure … though some complain of a decrease in night vision.