Some eye diseases progress unnoticed because they affect parts of the eye that cause no pain or redness. The retina and optic nerve can suffer severe damage without visible signs, and the brain unconsciously adapts to worsening vision.
Regular eye exams are, therefore, crucial, especially after age 40, when many “silent” eye conditions begin to appear.
Common diseases that steal sight
Dim or blurry vision is often dismissed as tired eyes or ageing. But difficulty reading in dim light or seeing at night may indicate early, irreversible eye disease. Even non-ocular symptoms like headaches, dizziness or imbalance can signal vision strain.
Glaucoma, the “silent thief of sight”, damages the optic nerve from elevated eye pressure. Peripheral vision is lost first, with central vision affected later and irreversibly.
Diabetic retinopathy occurs when high blood sugar damages retinal blood vessels. Vision may seem normal early on, but tiny leaks and bleeds gradually blur sight.
Age-related macular degeneration affects central vision, often starting as mild distortion or blurring. Cataracts slowly cloud the lens, causing dull, hazy vision and glare, but surgery can restore sight if done in time.
Hypertensive retinopathy from high blood pressure can damage retinal vessels before the patient knows they have hypertension.
In Malaysia, population data reflects these silent changes. The 2014 National Eye Survey found untreated cataract (58.6%), diabetic retinopathy (10.4%) and glaucoma (6.6%) were the leading causes of blindness in adults over 50.
More recent studies show some improvement, but prevalence remains significant: in Eastern Malaysia, blindness dropped from 1.4% to 0.8%, and in Sarawak from 1.6% to 0.6%.
In Kuala Lumpur outpatients, cataract was most common (21.3%), followed by glaucoma (12.3%) and diabetic retinopathy (8.4%).
When and how often to get checked
Adults should have eye exams every two years after age 40 and annually after 60. Those with diabetes, high blood pressure or a family history of glaucoma should be checked at least once a year.
Comprehensive exams include vision tests, eye pressure measurements, and retina and optic nerve evaluation; while advanced tests such as optical coherence tomography and visual field analysis detect early damage before symptoms appear.
Seek urgent medical care for sudden blurred vision, flashes of light, dark spots, distorted lines, loss of peripheral vision or eye pain. Even brief or one-sided symptoms may signal serious eye or brain conditions.
Good habits that protect your vision
Lifestyle choices matter – smoking, poor diet, and lack of exercise increase the risk of vision loss. A diet rich in leafy greens, fruits, fish and nuts supports eye health, while regular exercise helps control blood sugar and blood pressure. Wearing UV-protective sunglasses outdoors also reduces long-term damage.
Many people who feel fine are already losing vision slowly, so don’t want for symptoms to act. Much of Malaysia’s vision loss is preventable, and a simple, painless eye exam could mean the difference between saving or losing your sight.
Protect your vision as, once it’s gone, it may never return.
This article was written by Dr Rathna Ramayaj, consultant ophthalmologist at Columbia Asia Hospital Bukit Jalil.