Eyes are profoundly affected in diabetes. Different manifestations of diabetic eyes are in the form of cataracts involving lens, retinopathy involving retina and glaucoma involving intraocular pressure and optic nerve.

Diabetic Cataracts :

Cataracts are white opacities in the lens of the eyes. Formation of AGEs (Advanced Glycation End products) in the eye lens causes premature formation of cataracts. This depends on the duration of the diabetes status. Manifested by halos around lights, blurred vision, vision problems at night, sensitivity to light and glare. The treatment to this is by surgery.

Diabetic Retinopathy :

This is the most common cause of blindness. As a part of microvascular disease process, retinal vessels are affected by thickening of the basement membrane and the number of pericytes around blood vessels which support them, are decreased making the blood vessel wall weak. This weak wall can’t withstand the blood pressure and leading to microaneurysms at one stage of retinopathy. It is divided in to two stages.

Background retinopathy - Presents with retinal edema, exudates, microaneurysms and hemorrhages in retina. Cotton-wool spots due to ischemia of retina. In 1 - 2 months, these cotton-wool spots resolve leaving retinal depression.

Dot and blot hemorrhages are intra-retinal and are due to increased vascular permeability. Splinter hemorrhages are in nerve fiber layer of retina. Macular edema is due to vascular permeability and more common in this phase of retinopathy than proliferative phase.

Proliferative retinopathy - Presents with proliferation of retinal blood vessels and blood vessels in iris and optic nerve. These blood vessel generation is said to be due to release of growth factors. The blood vessels in optic nerve and retina rupture easily giving rise to vitreous hemorrhages. When these hemorrhages become fibrotic, they pull the retina causing retinal detachment.

Every patient need to be their eyes checked as soon as diabetes was diagnosed. And every year checkups and follow-ups are necessary.

Ophthalmologist dilates the pupil and see the inside of the eyes. Diabetics need regular eye checkups. Sometimes other investigations like fluorescein angiography (where certain dye is injected in to blood and the retinal vessels are checked through an opthalmoscope) and optical coherence tomography (that gives high resolution images of retina) are conducted.

Treatment is by good glucose control, hypertention and cholesterol treatment and photocoagulation. Photocoagulation treats the retinal vessels to stop leakage of fluid and blood.  Sometimes vitreous is removed called vitrectomy. This is done to stop retinal detachment and improve the sight.

Glaucoma :

Usually it is of open-angle type. It is of slow nature and presents after significant visual loss occurs. So a high index of suspicion is necessary to diagnose this condition. Here the patient often assumes that he requires new reading glasses. And loss of peripheral vision leading to tunnel vision. Eye pain, blurred vision, halos around light and redness of eyes are some of the manifestations of glaucoma. Topical eye drops and surgery are considered.

Tags: diabetic cataracts, diabetes, diabetic retinopathy, diabetic