Causes of Diabetic Retinopathy

When the doctors at California Retina Associates are asked what causes diabetic retinopathy, the short answer is: diabetes. But this response glosses over the complexities of diabetes and how complications of the disease can affect the health of the eyes and vision. A thorough understanding of how diabetes leads to diabetic retinopathy requires the knowledge of an expert team, like our San Diego diabetic retinopathy specialists.

Uncontrolled Blood Sugar Levels Damage the Blood Vessels in the Retina

Diabetes is a medical condition that affects the body’s ability to properly store and use sugar. When there is too much sugar in the blood, it can damage blood vessels around the body, including those tiny vessels that nourish the retina, or the light-sensitive tissue that lines the back of the eye.

Early versus Advanced Diabetic Retinopathy

There are two types of diabetic retinopathy: early (“nonproliferative”) diabetic retinopathy and advanced (“proliferative”) diabetic retinopathy. In nonproliferative diabetic retinopathy, high levels of sugar in the blood cause the blood vessels of the retina to swell and leak fluid, including small amounts of blood and possibly fat deposits. This leakage may cause the retinal tissue to thicken and swell, clouding or blurring vision. Sometimes the central portion of the retina, called the macula, also thickens and swells. This is known as diabetic macular edema and is the most common cause of vision loss in people with diabetes.

Without diabetic retinopathy treatment, nonproliferative diabetic retinopathy can advance into proliferative diabetic retinopathy. Proliferative diabetic retinopathy is very serious. In the more advanced form of the disease, the damaged blood cells actually close off and stop providing blood and oxygen to the retina. When this happens, the eye grows new, abnormal blood vessels that also leak blood and fluid. This blood and fluid can fill the vitreous, which is the clear jelly-like substance that fills the eye. When the blood and fluid fills the vitreous, it is known as vitreous hemorrhage, and can cause the appearance of dark specks, spots or clumps called floaters.

The abnormal blood vessels associated with proliferative diabetic retinopathy can also trigger the development of scar tissue in the retina; eventually this scar tissue can cause the retina to detach from the back wall of the eye (this is known as retinal detachment). Proliferative diabetic retinopathy can also interfere with the circulation and outflow of fluid from the eye, causing a spike in intraocular pressure and a disease called glaucoma.

Preventing Diabetic Retinopathy

Understanding what causes diabetic retinopathy underscores the importance of keeping blood sugar levels under control. If you have diabetes (and especially if you have had it for years), it’s crucial to work with your medical team to control the amount of sugar in your blood. Taking medication as prescribed, attending all doctor’s appointments and living a healthy lifestyle are essential for diabetic retinopathy prevention.

Having an understanding of the types of diabetic retinopathy and diabetic retinopathy complications also highlights how important it is to see an eye doctor regularly for exams. Identifying the early signs of nonproliferative diabetic retinopathy provides a prime opportunity to start treatment intervention and lower the chances of the disease progressing and causing irreversible vision loss.

Diabetic Retinopathy San Diego

For more information about the causes of diabetic retinopathy, our team at California Retina Associates encourages you to call (619) 425-7755 or (760) 352-7755 or email our practice today. We offer three convenient locations throughout Southern California to serve San Diego County and beyond.