During an appointment with an ophthalmologist, intraocular pressure is measured. What is it for, and what does it reveal?
The aqueous humor, translucent liquid contained in the eye, is in continuous regeneration. Only, if the balance between production and resorption of humor is disturbed, the eye pressure will increase.
The normal value of this ocular tension must be below 20 millimeters of mercury. It should be added that this measurement may change somewhat with the ambient light.
Eye pressure: A very quick test
In the ophthalmology practice, eye pressure will be measured either with a device called a contact tonometer or an electronic version.
The first will make his measurement with a cone in contact with the cornea following instillation of a drop of anesthetic product. The improved version will pulsate air and therefore avoid any contact with the organ. The result is immediate, and the examination completely painless.
Cause of ocular hypertension
Checking for glaucoma is the main reason for taking too large a measurement. It is an eye disease characterized by an increase in intraocular pressure with damage to the head of the optic nerve and an alteration, a narrowing of the visual field. Blindness can be the final stage of this pathology.
Showing only few signs in the original stage, glaucoma must be screened regularly following the age of 50, at the recommended frequency of once every two years.
But ocular hypertension can also be the consequence of a tumor or even of uveitis, that is to say an inflammation which manifests itself by a red and painful eye.
Factors favoring high eye pressure
- Age: the pressure generally increases following 40 years;
- Drug treatment, and more specifically corticosteroids, especially following three months of use;
- Apneas of sleep;
- Certain sports such as archery, biathlon, apnea which require blocking the breath;
- The use of wind instruments that increase eye pressure.
How to reduce eye pressure?
Here is what can be implemented:
- first-line eye drops: beta-blocking eye drops or eye drops incorporating anhydrase inhibitors should reduce the secretion of aqueous humor;
- the surgery is considered when the alteration of the optic nerve causes a degradation of the visual field. It consists of the creation of a valve to promote the elimination of humor;
- the laser will be recommended when eye drops are not effective enough, in one or two sessions.