Glaucoma is a condition wherein an increased intraocular pressure damages the optic nerve, thereby affecting vision. A fluid known as aqueous nourishes the front part of the eye. In a normal eye, the rate of production of aqueous matches the rate of its drainage, thereby maintaining optimal pressure inside the eye.
With age, disease, trauma or other factors, the channels carrying this fluid may get blocked, increasing the pressure inside the eye. This increased pressure damages the optic nerve, which is the conduit of visual messages to the brain. Working silently, glaucoma damages the outer or peripheral vision first while maintaining the central vision.
You are at risk if...
You are 45 years of age or above.
You have a family history of glaucoma.
You have health problems such as diabetes, hypertension or thyroid disease.
You suffer from myopia or nearsightedness.
You have had ocular trauma or intraocular surgery in the past.
Symptoms
Inability to adjust the eyes to darkened rooms such as theatres.
Poor night vision.
Frequent changes in eyeglass prescription.
Gradual loss of peripheral vision.
Blurred vision.
Feeling of a blind area in the eye.
Seeing rainbow coloured halos around lights.
Severe eye pain, facial pain, nausea and vomiting.
Red eye.
(The author is chairman, Centre for Sight)