Stages of Diabetic Retinopathy

Moderate Nonproliferative Retinopathy is the second and slightly more severe stage of Diabetic Retinopathy. It is similar to the mild stages, but with more extensive changes. During this stage, some of the small blood vessels in the Retina may become damaged enough so that they close off. The closure of these tiny blood vessels causes a decrease in the supply of nutrients and oxygen to certain areas of the retina which is termed ischemia.

Severe Nonproliferative Retinopathy is the next stage of Diabetic Retinopathy. Severe Nonproliferative Retinopathy is characterized by an extensive amount of retinal blood vessel damage and ischemia. Patients with severe Nonproliferative Retinopathy are at a high risk of going to the next stage of retinopathy – the proliferative stage. In order to properly assess the amount of retinal damage and make appropriate recommendations, it may be necessary to perform a diagnostic test called a Fluorescein Angiography (FA). If this is necessary, prior to starting your intravenous fluorescein angiogram, drops will be placed in your eyes to dilate your pupils. Next, you will receive an injection of a dye called sodium fluorescein. After approximately 15 seconds the dye will begin to circulate throughout the retinal blood vessels. Using a specialized retinal camera, a series of photographs of the retina are taken to study the circulation of blood through the retinal blood vessels. Using the Fluorescein Angiogram, it is possible to observe the circulation and integrity of the blood vessels in the retina so that he can identify any blood vessels that might be leaking and the amount of ischemia.

Proliferative Retinopathy is the most severe stage of Diabetic Retinopathy and carries a significant risk of vision loss. In an attempt to compensate for the lack of oxygen supply, areas of the retina send signals to stimulate the growth of new blood vessels in order to try and reestablish the supply of oxygen.  These chemical signals stimulate the growth of new, but abnormal blood vessels, a process called neovascularization. When Retinal Neovascularization is present, you have progressed into the stage of Diabetic Retinopathy called Proliferative Retinopathy. It might seem that new blood vessel growth or neovascularization is a desirable event, as it will provide the retina with greater blood flow and thus more oxygen and nutrients. However, this is not the case at all. Retinal Neovascularization is formed from new blood vessels that are extremely fragile and tend to break easily and hemorrhage into the Vitreous. If left untreated, Proliferative Retinopathy may lead to bleeding into the Vitreous and Retinal Detachment with profound vision loss.

It may be possible for patients to have Proliferative Retinopathy and Retinal Neovascularization and yet still have good vision. Even if Proliferative Retinopathy and Retinal Neovascularization do not appear to be causing any vision loss, it is critical that this stage be treated as quickly as possible in order to stop the progression and preserve good vision.