There are several tests that your eye care provider will do to determine if you have glaucoma. First is to check your eye pressure, as individuals with elevated eye pressures have a greater risk for glaucoma. Second is often a test called optical coherence tomography; this scan analyzes the optic nerve of the eye to see if there is potential damage. Finally, a visual field test will be performed to determine if there has been a loss of peripheral vision. Recently, additional tests have become available which provide further information useful in risk stratifying patients, but these are beyond the scope of this blog.
Frequently, patients will tell me that they have been told in the past they might have glaucoma, but they don’t know what that means, or what they ought to do. I explain this concept to patients as follows: we know some patients have glaucoma because they have all the signs (elevated eye pressure, optic nerve damage, and peripheral vision loss), and we know many patients who definitively don’t have glaucoma because they have none of the above signs. However, as eye care providers we frequently encounter patients who have only one of the signs of glaucoma, but not the rest; a common example, is elevated eye pressure, but with healthy optic nerves and normal visual fields. What are we to do in these situations? Most commonly, we will simply monitor these borderline glaucoma patients (also known as glaucoma suspects) more closely. Typically, I see glaucoma suspect patients every 6 months and repeat their diagnostic exams annually. As I explain to my glaucoma suspect patients, more often than not they will not go on to develop glaucoma, and if they do, we will hopefully have caught it and treated it before it ever affects their vision.