How come an eye specialist has diagnosed advanced glaucoma in one of my eyes yet I have noticed no deterioration in my vision in that eye?

Glaucoma is only very rarely discovered by a patient from his or her own observations. The most common kind, "open-angle," does not cause pain, does not affect your straight-ahead visual acuity (until the very advanced stages), nor does it occur suddenly. Glaucoma's effect on vision is a very slow constriction of your field of view -that is, from the outside in.

When I taught at the large, downtown "charity" hospital, it was not an uncommon experience to see an older person who came to the clinic when he discovered there was not vision in one eye when the other, seeing eye was accidentally covered for a moment. That is why glaucoma used to be called "the sneak thief of sight."

_Written by J. Trevor Woodhams, M.D. - Chief of Surgery, Woodhams Eye Clinic