My eye pressure is normal, so I do not have glaucoma?
The pressure number alone does not rule out glaucoma, and a high number does not mean you have it.
Many people think glaucoma simply means high eye pressure. Pressure matters, but that is not the whole story. Glaucoma is a disease of the optic nerve, and a single number cannot measure it.
Normal pressure and nerve damage
Eye pressure is usually between 10 and 20 mmHg. In one type of glaucoma the pressure stays in this range, yet the optic nerve is damaged and sight is lost. So a normal number neither rules out glaucoma nor lowers your risk.
The reverse is true as well: some people with high pressure never develop glaucoma.
Why do we not notice it ourselves?
The most common type has no early symptoms and no pain. Side vision fades slowly while central vision stays intact for a long time. About half of people with glaucoma do not know they have it.
What does diagnosis need?
As well as measuring pressure, the doctor looks at the optic nerve, checks the drainage angle, tests side vision and measures corneal thickness.
Who should take it more seriously?
If you have a family history, are over 60, or have thin corneas, a high prescription, diabetes or migraine, or have used steroids for a long time, ask your doctor how often to be examined. People at higher risk usually need a full exam every one to two years.
What if it is diagnosed?
Lost sight does not come back, but treatment can prevent further loss. Do not stop your drops without your doctor’s advice.