Laser coagulation refers to a type of laser surgery that uses light in the green spectrum to force tissues to clot, or coagulate. This spectrum of light is absorbed by the hemoglobin in red blood cells which, in turn, seals off blood vessels. Once the tissue loses its blood supply, it shrinks and will eventually be reabsorbed by the body. Laser coagulation often is used to treat varicose veins and to shrink cancer tumors, and a form of the procedure is commonly used in eye surgeries. The major advantage of this type of surgery is that it can usually be completed in an outpatient setting with minimal discomfort for the patient. In addition, the risks of blood loss and infection are heavily diminished because the laser simultaneously closes off the blood vessels and sterilizes the area during the procedure.
A subtype of this surgery, photocoagulation, is the type of laser surgery employed in most eye surgeries. This type of eye surgery is considered to be far superior to previous methods. In the case of a torn or detached retina, for example, the physician often uses an argon laser through a special contact lens in order to "weld" the retina to the underlying eye tissue. Photocoagulation is considered the best treatment approach for diabetic retinopathy as well and can reduce the chances of severe vision loss by 50 to 75% if performed in the early stages of the disease. Other eye conditions that can be successfully treated with photocoagulation include macular degeneration, retinal ischemia, retinal detachment, and ruptured blood vessels in the eye.
Prior to laser coagulation, the only surgical treatment for severe varicose veins was vein stripping. This procedure required the surgeon to make numerous closely-spaced incisions along the legs and to strip the veins in each section. Despite a painful recovery period lasting several weeks, vein stripping was rarely successful and often required additional procedures. Laser coagulation, on the other hand, requires one or two small incisions that are usually made at the knee or groin. It can also be performed on an outpatient basis, has a much shorter recovery period, and rarely requires additional surgery.
Laser coagulation is not limited to use in optical and venous surgeries. Some types of cancer have also been successfully treated by focusing the laser on the blood vessels that supply the tumor with oxygen and nutrients. The tumor will then begin to shrink and will eventually be reabsorbed by the body. Although the use of lasers in the treatment of cancer is promising, many factors are considered before attempting the use of lasers to treat some types of tumors. The use of laser coagulation procedures is increasing in many others branches of medicine as well.