In PDR, the neovascularization may cause scar tissue to develop. The neovascularization and the scar tissue grow along the surface of the retina and attach firmly to the back surface of the vitreous gel. The vitreous gel pulls on the blood vessels and scar tissue and lifts them up. Because the neovascularization and scar tissue are attached to the retina, the retina is also lifted up. When the retina separates from the back surface of the eye, it is called a retinal detachment. Because the retina is pulled off, it is called a traction retinal detachment. The scar tissue can also tear the retina and cause a retinal detachment.

When a retinal detachment occurs, the patient may notice a shadow or very large dark area in the vision. When the retinal detachment extends to the macula, the dark shadow will be straight ahead and vision may be poor. The neovascularization and scar tissue also can cause visual loss because they can wrinkle the retina.

The only way the patient can regain any vision is for the retina to be reattached and the neovascularization and scar tissue to be removed from the surface of the retina. This is accomplished by vitrectomy surgery. The surgeon removes the vitreous gel from the eye so that it stops pulling on the retina; the traction is released. The surgeon may remove the scar tissue from the surface of the retina so that there is no wrinkling of the retina. The detached and wrinkled retina should flatten and smooth out. The surgeon may also perform panretinal laser photocoagulation to prevent further development of neovascularization and rubeosis.

The surgeon also uses laser inside the eye to seal any tears of the retina. If there are tears in the retina, the surgeon may place a large gas bubble in the eye to press the retina completely against the back wall of the eye while the laser surgery takes hold. In order to accomplish this, you may be asked to position your head facing down or up for a week following the surgery. In time, the gas bubble will disappear and be replaced by the eye's own fluid.