Glaucoma is a common eye condition characterized by a buildup of fluid in the eye. When the passages in the eye that drain excess fluid become clogged, the pressure from the fluid can damage the optic nerve. Glaucoma does not present any visible symptoms until vision loss has already started to occur. If left untreated, glaucoma can eventually lead to complete vision loss. Increased pressure in the eye is a sign of glaucoma, therefore one of the first and most important screening tests used to diagnose glaucoma is an intraocular eye pressure test. The only way to preserve vision is to undergo regular glaucoma screening tests.
A common glaucoma test is the "puff-of-air" test, technically known as non-contact tonometry, or NCT. Based on your eye's resistance to the puff of air, the machine calculates your intraocular pressure (IOP). A tonometry test is recommended for all adults during routine eye exams, unless there is a contraindication. Tonometry may be postponed if there is an eye injury or if there is an ulcer on the cornea. Children are not typically given a tonometry test.