Diabetic Retinopathy

Diabetes Mellitus is a condition which decreases the ability of the body to use & store sugar due to a deficiency in the synthesis of insulin, the hormone of the pancreas, or an insensitivity to the action of insulin.

Diabetic Retinopathy, a complication of diabetes, is caused by changes in the small blood vessels of the retina. These damaged blood vessels may leak fluid & blood, or show growth of fragile new vessels and scar tissue thereby affecting vision.Diabetic retinopathy is one of the most common causes of blindness in those over 45 years of age.

Diabetes is a rapidly emerging problem in developing world.  India is estimated to have 33million diabetics and this is likely to increase to 57 millions by 2025.

It is estimated that 80% of diabetics will have some form of diabetic retinopathy and 25% will have advanced form of diabetic involvement of retina (proliferative diabetic retinopathy) at 15years. Compared to non-diabetic, a diabetic with retinopathy has 25 times greater risk of blindness. Hence, diabetic involvement of the eye has a major affect not only on the individual but also places a great burden on the family. This is particularly tragic because timely treatment can prevent up to 60-70% of vision loss due to D.R provided the condition is detected early and treated adequately.

Types of Diabetic Retinopathy:

Background disease (BDR) is an early stage in which sight is not seriously affected.

In some cases vision is affected when the leaking fluid collects at the macula, the part of retina responsible for detailed vision. This is called ‘diabetic maculopathy’.

Proliferative diabetic retinopathy (PDR) is the more serious type of retinopathy in which there is growth of abnormal, fragile new blood vessels and scar tissue on the surface of retina and optic nerve. These new vessels have weak walls and may rupture and bleed producing vitreous haemorrhage which blocks the light from reaching the retina while the scar tissue contracts and exerts pull on the retina lifting it up from its normal position. This is called tractional retinal detachment.

Symptoms:

Patients with significant changes of diabetic retinopathy can have good vision and be totally asymptomatic. Sight is usually unaffected in background diabetic retinopathy unless there is macular edema.

Black spots (floaters) of sudden onset often indicate a minor bleed in the eye, while sudden visual loss may occur due to extensive bleeding into the vitreous. Vision is also affected when there is traction at macula or traction induced detachment of retina involving macula.