Ocular Hypertension and Glaucoma Risk?

If a person has ocular hypertension (high eye pressure but no damage), how much of a risk does he/she have to get glaucoma?
I am taking an anti-glaucoma medication prescribed by my doctor because I have ocular hypertension, but I have read somewhere that some people do not end up getting glaucoma, even though they have high eye pressure.
So, is there really a risk and how much of it if you have this condition to end up with glaucoma?

Glaucoma is the medical name of high pressure within the eye. Even if asymptomatic it can insiduosly cause eye damage. In this regard it is bit similar to Arterial Hypertension which usually doesn't produce any symptoms but definitely lead to damage to body hence the name 'Silent Killer'.