A number of medical conditions can cause scar tissue or other unhealthy tissue to form in an eye. This scar tissue, which may be attached to part of the eye or floating freely, can cause problems ranging from causing you to see dark spots in your vision to causing complete blindness. Fortunately, in many cases, the scar tissue can be safely removed.
A large number of surgical procedures can be performed on eyes; many of the ones involving scar tissue fall under the heading of vitrectomy. This type of surgery involves the physical insertion of microsurgical tools to either alter the fluids in the eye or to physically peel scar tissue off the light sensitive parts of the eye. In cases where the scar tissue is floating freely in the eye, a surgeon may decide to completely or partially drain the intraocular fluid. Because this surgery can have significant side effects, it is only done is cases in which floating scar tissue is significantly impeding vision. Often this procedure will involve the injection of air or gas into the eye to maintain the eye's pressure while the fluid is drained. When the fluid including the scar tissue is completely removed the eye refills itself quickly with fluid. In cases where the unhealthy tissue is firmly attached to part of the eye, the surgeon may make use of a variety of tiny tools in a procedure called membranectomy. These tools may include forceps (tiny tweezers) and small hooks. Sometimes the technique of visco-dissection, which involves separating the scar tissue from healthy tissue with a powerful, focused spray of fluid, may also be used. If the scar tissue is attached to the lens of the eye, the lens itself may be removed in a procedure called lensectomy.
While these types of surgery are often successful, they have a history of significant side effects. Some patents may suffer retinal detachment after surgery. More commonly, patients may develop a cataract due to bleeding in the as a result of surgery. Overall, however, most people who undergo vitrectomy are able to recover most of their vision. In some extreme cases, scar tissue in the eye may be a result of serious damage. In these cases, even if surgery were to remove the scar tissue, the eye would still be too damaged to allow normal vision.