Photo by Anthony Shkraba from Pexels

As part of a complete eye exam, a measurement of eye pressure will be taken. Most of us are familiar with the eye pressure test using a puff of air. Today, ophthalmologists use a more accurate device that measures pressure called tonometry, which measures pressure by direct contact with the eye.

How eye pressure is measured

Eye pressure is measured in millimeters of mercury (mm Hg). Normal eye pressure ranges from 12-22 mm Hg, and eye pressure of greater than 22 mm Hg is considered higher than normal. When the IOP is higher than normal, but the person does not show signs of glaucoma, this is referred to as ocular hypertension.

How the eye works

A normal function of a healthy eye includes the generation of a fluid called aqueous humor. The aqueous fluid is constantly being flushed and renewed in the eye. This process keeps pressure in your eye (called intraocular pressure or IOP) stable. When the flushing actions is not working properly, fluid builds up and pressure inside the eye rises, potentially causing damage to the optic nerve.

When eye pressure is elevated

Elevated eye pressure with no other symptoms is called ocular hypertension. This condition results in higher eye pressure usually resulting in no damage to the optic nerve. But some people lose vision even if the pressure is in the normal range, which is why this exam is an important part of a regular eye and vision check-up. Elevated eye pressure can lead to glaucoma, which damages the optic nerve and permanently reduces vision. If glaucoma is not treated, it can lead to total blindness.

How Is Eye Pressure Measured?

  • Eye drops are put in your eyes to numb them.
  • Then the doctor or assistant gently touches the front surface of your eye with a device that glows with a blue light. Other times a different handheld instrument is used.
  • Both methods apply a small amount of pressure to the eye.
  • This allows your ophthalmologist to measure the pressure inside each eye.
  • During this test, it is very helpful to relax and breathe normally.

Everyone’s eye pressure is different, and there is no single correct pressure for everyone. An eye exam with an ophthalmologist will determine the eye pressure range that is healthy for each individual.

Article source: American Academy of Ophthalmology aao.org

Our practice philosophy at Barth Vision & Optical is simple, though we like to think it reflects a profound sentiment. We are here to be of service, in the truest sense of the term. We  offer State-of-the-art eye examinations, A unique collection of fashion eye wear, Cataract surgery & consultation, LASIK vision correction, Eye Care Telemedicine. Call Today for an Appointment (707) 955-1120.