How Does Cornea Thickness Affect Intraocular Pressure?
DEC 11, 2013
Question:
I've been told normal eye pressures are less than 20. When I went to the doctor a few days ago mine were 22 to 24 in each eye; he then measured my cornea thickness and said it was thick enough to deduct points off the pressures and that they were actually in the normal range. Is that correct? I never heard of that before. My eyes today feel like they are sore/bruised—is that normal?
Answer:
You are correct that intraocular pressures are typically less than 20. However, that pressure measurement can be falsely elevated by a thicker, and potentially more rigid cornea. The Ocular Hypertension Treatment Study found that study patients with elevated pressures (greater than 24 mm Hg) and thicker corneas, were dramatically lower risk of developing glaucoma than those patient with elevated pressures and normal or thin corneas.
I don’t know what to say about the sore, bruised feeling that you have. It may be that the doctor performed several pressure measurements and pachymetry measurements (to determine your corneal thickness) and in so doing, irritated the surface of cornea a bit. Pressures in the low 20s are very unlikely to cause a sore or bruised feeling.