Diabetes, a state of altered  glucose metabolism, is a major risk factor for impaired vision. Due to chronically high blood sugar levels, eyes are damaged in many ways.

In diabetic patients, the vision keeps on fluctuating resulting in blurred vision. Diabetic individuals are at greater risk of developing weakness of eye muscles, leading to disturbances in near or far vision.

If one gets eyes examined during this time, there are chances that they may get wrong prescription for the eyeglasses Therefore, it is always advisable to get the number of corrective eyeglasses only when the sugar levels are normal.

One can develop diplopia (double vision) due to weakness of eye muscles caused by diabetes. This makes routine working difficult.

If one develops damage to the nerves supplying the eye or paralysis of the facial muscles due to uncontrolled diabetes, their eyes are also damaged, affecting vision. There may be inability to close the eye completely. In such cases, it is advisable that the affected individual uses dark glasses while moving out to prevent exposure to dust or strong sunlight, which can hurt the eye or damage it further.

While sleeping, it is necessary to keep the eye covered with a soft cotton cloth or patch, otherwise there is a potential risk of some insect biting the eyes.

In some unfortunate persons, the optic nerve (nerve responsible for vision) may be damaged, leading to sudden blindness.

Individuals with diabetes are susceptible to develop cataract in the eyes at a younger age. The lens starts becoming opaque and progresses rapidly to complete opacification, thus affecting vision severely.

Due to increased susceptibility to severe infections in diabetics, unattended mild infection of the eye can progress to infection of all layers of the eyes.

Damage to the retina (image forming screen of the eye) is the greatest risk faced by diabetic persons.  Retinopathy invariably develops after 15 to 20 years of diabetes. In uncontrolled diabetes, it develops earlier and in more severe form. Due to diabetic retinopathy, initially one has blurred vision. Later on, the patient begins to see spots and distorted images. Due to formation of new blood vessels in the retina, there is increase in the pressure of fluid within eyes, resulting in glaucoma.

Along with diabetes, presence of uncontrolled hypertension, kidney failure and or severe anemia are conditions which can further exacerbate the eye problems.

People working with computers for long time are more prone to develop damage to eyes due to uncontrolled diabetes.

Diabetic persons should be aware of the potential damage to eyes caused by uncontrolled diabetes. They should try to keep their diabetes well controlled by means of diet, life style measures and regular medication. Smoking and alcohol should be avoided.

Use of plenty of green vegetables and fruits helps to strengthen the eye muscles and keeps eyes healthy. While reading or writing, attention should be given to see that adequate light falls on the book kept in front. After working with a computer for about an hour, it is desirable to have a break of few minutes to give rest to the eyes. One should avoid direct exposure to dust and strong sunlight by using sunglasses.

Dr Rachna Pande is a specialist in internal medicine at Ruhengeri Hospital

rachna212002@yahoo.co.uk