There are usually no warning signs of glaucoma until there is already significant vision loss. For this reason, an annual eye examination that includes tonometry is essential to rule out early signs of glaucoma and protect your vision.
A very common test for glaucoma makes use of a non-contact tonometer (NCT). A puff of air is blown onto the eye and then, based on the eye’s resistance to the puff of air the instrument calculates the intraocular pressure. The test is completely painless and takes a few minutes to complete.
Intraocular pressure may vary at different times during the day. If your pressure is found to be higher than normal, you may be asked to return at a different time of day for another reading. If the reading remains high further tests and referral will be indicated.