Question
I am a white male, age 39. What is the normal IOP level for Caucasians? Mine is around 21 in both eyes. I live in Japan, and was diagnosed with Glaucoma after one consultation with a Japanese eye doctor. A resent yearly health check, showed that a cave-in around the optical nerve in both eyes.Another Japanese eye doctor I consulted stated that you cannot just diagnose Glaucoma after just one check, but need to establish what the baseline IOP level is first. I am nearsighted and the last eye doctor mentioned that a cave-in of the optical nerve is common among nearsighted persons, and do not necessary indicate Glaucoma. I can email photos of my optical nerve for both eyes, if needed. Thank you for
your advice.
Answer
Please understand that in the current definition of Glaucoma (the more common, non-painful, open-angle variety), Intraocular pressures are not even mentioned. This is in stark contrast to the view of glaucoma of two-three decades ago where glaucoma = higher than normal intraocular pressures. Having that said, glaucoma still is more common in persons with pressures over 30 than in persons having pressures under 15. However there are those who have glaucoma with a pressure of 12 and those who do not have glaucoma with pressures of 28. The true definition of glaucoma is a condition called optic neuropathy , in which the optic nervehead is damaged with excavation and nerve fiber layer dropout in which the intraocular pressure in that individual is too high for his/her optic nerve to withstand resulting in visual field loss. Visual field testing, HRT, corneal pachymetry, optic nerve head assessment and risk factors as, age, strong myopia prescription, corneal thickness (the thinner the cornea the higher the risk for glaucoma), family history, diabetes mellitus, headaches, spots or flashes of light, high blood pressure, circulatory problems, etc.
So as you can see from this explanation, Glaucoma is more than just an intraocular pressure reading, which by the way should be performed at least on three different occasions and times because of daily fluctuations in pressures (diurnal variation), but as a general rule IOPs of 10-21 are considered to be the "normal" range Dr. Ken
