The anterior chamber depth of the eye or ACD is the term used to refer to the limited ocular structure in front of the eye. cornea and behind iris and crystalline.
In that space is the aqueous humor, the substance responsible for keeping the metabolism of some structures located in the anterior part of the eyeball balanced.
En Área Oftalmológica Avanzada We explain below what the depth of the anterior ocular chamber is.
What is the depth of the anterior chamber of the eye
The anterior chamber is the space between the cornea and the iris. It is where the aqueous humor is located, responsible for nourishing the surrounding tissues of the front part of the eye with oxygen, proteins and glucose.
The ACD is the measurement of the size occupied by that space that we know as the anterior chamber.
Knowing the depth of the anterior chamber of the eye is important to perform a refractive surgery and calculate the power of intraocular lenses to correct the falls y presbyopia.
As measured?
There are different ways to measure the depth of the anterior chamber of the eye. Among all, the most used today is the Van Herick technique.
The Van Herick technique
This technique allows knowing the ACD in the iridocorneal and chamber angles.
The technique is carried out with slit lamp and consists of directly illuminating the sclerocorneal limbus while the lighting and observation system form an angle of 60º.
The observation system must be located in front of the eye and the light that is emitted must be at maximum intensity.
The test can be done from the nasal side or from the temporal side, the latter being the most used.
During the examination, the corneal thickness, the dark space that represents the camera and a segment of the iris can be observed.
The exam is quantified in grades as follows:
- 0 Grade: There is no depth, the cornea and the iris are in contact. There is a high risk of angle-closure glaucoma.
- 1 Grade: ACD less than a quarter of the corneal thickness. The angle between the cornea and the iris is 10 degrees.
- 2 Grade: ACD equal to a quarter of the corneal thickness. The angle between the cornea and the iris is 20 degrees.
- 3 Grade: ACD equal to or greater than half the corneal thickness. The angle between iris and cornea ranges between 20 and 35 degrees.
- 4 Grade: ACD greater than or equal to corneal thickness. Angle between iris and cornea between 35 and 45 degrees.
Which instrument measures the anterior ocular chamber depth?
The instrument that measures the ACD is the surveyor.
At present, there are many types of topographers that allow an in-depth examination of the ocular structure and a detailed study of the anterior area and the lacrimal structure.
El Keratograph He is one of the most modern surveyors that exist today. It has a high density camera and a powerful lighting system to measure the depth of the anterior ocular chamber.
Do you need more information on aspects related to the depth of the anterior chamber? In Área Oftalmológica Avanzada We will solve all your doubts and questions. Contact us!
