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Intraocular pressure

The ocular structure contains a substance known as aqueous humor.

This fluid puts pressure on the solid structures of the eye, such as the crystalline or the cornea, and this pressure is known as IOP or intraocular pressure. 

The balance in the production and elimination of aqueous humor in the eye is what allows to maintain a stable intraocular pressure.

En Área Oftalmológica Avanzada We explain below what intraocular pressure is and how it is measured. 

What is intraocular pressure?

The intraocular pressure is the pressure exerted by the liquids of the eye against the solid structures of the eye. 

The aqueous humor is found in the anterior chamber of the eye, delimited by the cornea, the iris and the crystalline

In the eye, a circuit is created where a small amount of aqueous humor enters the anterior chamber of the eye at the same time that the same amount of aqueous humor already existing in it is drained. 

The aqueous humor drains through the Shlemm channel or trabecular meshwork which is located around the iris.

The balance between the entry and exit of liquid is what allows a healthy eye to have a normal intraocular pressure. 

When more liquid enters than it comes out, or vice versa, there is a mismatch in intraocular pressure that can affect the optic nerve and cause important conditions such as glaucoma

How is intraocular pressure measured?

The intraocular pressure is measured with the help of a tonometer.

Currently, the air tonometer is an excellent piece of equipment for examining IOP, since it does not suggest any type of direct contact with the eye and the measurement is carried out automatically. 

IOP can be measured with any type of tonometer. These medical teams aim to study how the cornea behaves when faced with the intraocular pressure of the eye.

This procedure is known as tonometry.

Values ​​of intraocular pressure

The normal values ​​of the IOP range from 15 mmHg. and the 16 mmHg.

La ocular hypertension It happens when the intraocular pressure is higher than normal. We consider that there ocular hypertension (eye pressure above normal) from 20 mmHg.

La ocular hypotension means that the intraocular pressure is lower than normal values. Ocular hypotension is considered to exist when tonometry values ​​are less than 10mmHg.

Any result below or above between 10 mmHg. and 20mmHg. of intraocular pressure or IOP should be considered abnormal. 

High eye pressure

When the values ​​of the intraocular pressure are high, the patient is considered to have ocular hypertension.

La high intraocular pressure or ocular hypertension is a symptom of conditions such as glaucoma. In any case, glaucoma can also be manifested by other causes such as age, the progressive loss of thickness of the nerve fiber layer (RNFL) ... and this is known as normal tension glaucoma

Ocular hypertension can cause loss of vision, although there are those who suffer from ocular hypertension without this happening.

In people with glaucoma, ocular hypertension goes deteriorating the optic nerve progressively and, if proper follow-up is not performed, it can cause blindness.

Low eye pressure

Low ocular pressure or ocular hypotension can be a risk factor for visual health.

Excessively low levels of eye pressure can also trigger glaucoma and cause vision loss. 

Eye pressure is usually low in older adults who are being treated with some type of antihypertensive therapy. 

When is it recommended to measure intraocular pressure?

The intraocular pressure should be measured at least once a year in a preventive manner.

In fact, its measurement is part of the routine examinations that make up the annual ophthalmological check-up. 

Also, it is recommended to measure the intraocular pressure periodically during the third Age, stage where the diagnosis of glaucoma is more frequent. 

Every patient diagnosed with glaucoma must rigorously examine their eye pressure to verify that the disease is being treated correctly in order to prevent total deterioration of the optic nerve.

Do you want to perform a routine checkup to measure intraocular pressure? Contact us in Área Oftalmológica Avanzada and we will gladly assist you!

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Intraocular pressure (IOP)
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Intraocular pressure (IOP)
A disorder of intraocular pressure can affect the optic nerve and cause serious conditions. We tell you what it is and how it is measured.
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Área Oftalmológica Avanzada
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intraocular pressure, intraocular pressure, eye pressure, eye pressure
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