How to measure eye pressure

Eye pressure, which is also called intraocular pressure, is referred to as the fluid pressure inside the eye. Eye pressure is controlled by a watery fluid called aqueous humor, which fills the front part of the eye. In a normal eye, there is a balance between the production and drainage of this fluid. But in some cases, this balance is disturbed when the flow of aqueous humor out of the eye becomes restricted. As a result, the eye pressure rises.

Uncomfortable eye feeling calls for a visit to eye doctor

Increased eye pressure always causes patient to experience an uncomfortable feeling in the eye or even eye pain. It can be a sign of glaucoma, which can develop to be a very serious eye problem if no preventive treatment is applied. It is a must to visit an eye doctor when there is a feeling of high eye pressure.

Two ways to measure eye pressure

Eye pressure can be measured by an instrument called applanation tonometry. The test is called tonometry. The patient just looks close at the instrument, which blows a puff of air into the eye. And then a special sensor is used to detect the pressure on the surface of the eye. In other words, the tone or firmness of the eye surface is measured. This process lasts less than a second. Eye pressure can also be measured by an instrument resembling a pen, which will be placed onto the surface of the eyeball just like putting a contact lens onto the eye.

Why eye pressure measurement is important

Eye pressure is measured in millimeters of mercury (mm Hg). Normal eye pressure ranges from 10 to 21 mm Hg. An eye pressure higher than 21 mm Hg is formally called ocular hypertension. Also called intraocular pressure (IOP), eye pressure at an abnormal level may damage the optic nerve, which collects all of the visual information from the retina and also transmit them to the brain. To a large degree, optic nerve system functions as a bridge between the eye and the brain. However, different levels of increased intraocular pressure may gradually harm this critical system.

Glaucoma is the most likely consequence

As mentioned in the second paragraph, increased eye pressure can be a sign of glaucoma. The reason is that the damage to optic nerve will gradually lead to decreased peripheral vision and loss of some nerve tissues, which are exact symptoms of glaucoma. Due to this reason, the most common way to “treat” glaucoma is controlling eye pressure.