Chambre antérieure de l'œil

The anterior chamber (AC) is the aqueous humor-filled space inside the eye between the iris and the cornea's innermost surface, the endothelium. Hyphema, anterior uveitis and glaucoma are three main pathologies in this area. In hyphema, blood fills the anterior chamber as a result of a hemorrhage, most commonly after a blunt eye injury. Anterior uveitis is an inflammatory process affecting the iris and ciliary body, with resulting inflammatory signs in the anterior chamber. In glaucoma, blockage of the trabecular meshwork prevents the normal outflow of aqueous humour, resulting in increased intraocular pressure, progressive damage to the optic nerve head, and eventually blindness. The depth of the anterior chamber of the eye varies between 1.5 and 4.0 mm, averaging 3.0 mm. It tends to become shallower at older age and in eyes with hypermetropia (far sightedness). As depth decreases below 2.5 mm, the risk for angle closure glaucoma increases. Determining the anterior chamber depth (ACD) is important in estimating the risk of angle closure glaucoma. There are various method of measuring ACD, including examination through a slit lamp, ultrasound and Scheimpflug photography. These methods require sophisticated examination equipment and expertise. A simpler clinical method of quantitatively estimating ACD using smartphone photography (EZ ratio) was developed by Dr Ehud Zamir from the Centre for Eye Research Australia, the University of Melbourne, and published in 2016. The EZ ratio method is one way to calculate the estimated anterior chamber depth. To start, the patient looks at a target in the distance with one eye covered. The examiner takes a digital photograph of the open, examined eye, from the side, perpendicular to the visual axis (a profile photograph). The following parameters then need to be measured in the photograph, using a personal computer or a smartphone (figures 1,2):

The pixel distance between the limbus (the junction between clear cornea and white sclera) and the front of the cornea.

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Cataract is the leading cause of blindness worldwide. The clouding of the human eye lens is called "Grauer Star" in German. In the industrialized countries this process of increased blindness is corre

EPFL2001

Chambre postérieure de l'œil

La chambre postérieure de l'œil est un petit espace dans la partie postérieure du globe oculaire, entourant le cristallin, limité par l’iris et par le corps ciliaire, et rempli par l’humeur aqueuse. La chambre postérieure se situe entre l'iris en avant et la zonule de Zinn et le corps ciliaire en arrière . L'iris et la zonule le séparent respectivement de la chambre antérieure et du corps vitré. C'est un espace de forme annulaire qui trouve sa place autour de la lcristallin, est traversé par les fibres de la zonule ciliaire et donc rempli d' humeur aqueuse .

Corneal endothelium

The corneal endothelium is a single layer of endothelial cells on the inner surface of the cornea. It faces the chamber formed between the cornea and the iris. The corneal endothelium are specialized, flattened, mitochondria-rich cells that line the posterior surface of the cornea and face the anterior chamber of the eye. The corneal endothelium governs fluid and solute transport across the posterior surface of the cornea and maintains the cornea in the slightly dehydrated state that is required for optical transparency.

Slit lamp

In ophthalmology and optometry, a slit lamp is an instrument consisting of a high-intensity light source that can be focused to shine a thin sheet of light into the eye. It is used in conjunction with a biomicroscope. The lamp facilitates an examination of the anterior segment and posterior segment of the human eye, which includes the eyelid, sclera, conjunctiva, iris, natural crystalline lens, and cornea. The binocular slit-lamp examination provides a stereoscopic magnified view of the eye structures in detail, enabling anatomical diagnoses to be made for a variety of eye conditions.

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