The eye chambers are formed by two cavities, the anterior and posterior chambers, and are located in the anterior part of the eye just behind the cornea and still in front of the lens. The two eye chambers communicate with each other and are filled with aqueous humor, which primarily serves to supply nutrients to the lens and cornea and maintain the necessary intraocular pressure.
What are the chambers of the eye?
The eye chambers consist of the larger anterior chamber and the much smaller posterior chamber. The anterior chamber of the eye is located just below the cornea. It is delineated inwardly by the iris and the pupillary muscles (musculus sphincter and dilatator pupillae) to constrict and dilate the pupil. Through the pupil, it is in communication with the lens and the posterior chamber of the eye. The posterior chamber of the eye is bounded anteriorly by the posterior aspect of the iris and pupillary muscles and posteriorly by the anterior aspect of the vitreous. That is, iris and pupillary muscles (smooth muscle cells under autonomic control) form the main demarcation between the posterior and anterior chambers of the eye. Both chambers are filled with aqueous humor, a crystal-clear electrolyte in which proteins, hyaluronic acid, ascorbic acid (vitamin C), and other substances are dissolved.
Anatomy and structure
Anatomically, the anterior and posterior chambers of the eye do not have their own structure delineated by a membrane; rather, they are cavities created by the delineation of other structures. The anterior chamber is bounded anteriorly by the cornea, so that the aqueous humor in the chambers of the eye comes into direct contact with the cornea and an exchange of substances can take place between the cornea and the aqueous humor. The posterior chamber of the eye is delimited posteriorly by the anterior surface of the vitreous humor and centrally by the anterior surface of the lens. The annular ciliary muscles project into the posterior chambers of the eye from the outer edge and use zonula fibers to effect accommodation at long distances. The ciliary muscles contain special cells that produce aqueous humor and release it into the posterior chamber of the eye. At the outer edge of the anterior chamber, an angle is formed between the iris and cornea, called the chamber angle, which has structures (trabecular meshwork) that can receive the “spent” aqueous humor and deliver it into an annular vein, Schlemm’s canal, into the venous circulation for “reprocessing.”
Function and Tasks
In the two chambers of the eye and at their edges are movable structures that are necessary for accommodation of the eye, that is, for changing the shape of the lens to adjust focus at long or short distances, and other structures whose function is to make the pupil narrower or wider, depending on the strength of the incidence of light. This means that, on the one hand, the structures that are mobile and variable in shape claim variable space for themselves, and on the other hand, other structures of the eye also require a certain amount of pressure to keep the eye in the necessary shape. Therefore, one of the two main tasks and functions of the two chambers is to maintain the required pressure, the intraocular pressure, at about 15 to 20 mm Hg (middle-aged adult) by regulating the production and outflow of aqueous humor. The second main function is to supply nutrients and energy to adjacent structures that cannot be perfused. These are primarily the lens and the cornea. The lens, cornea and vitreous body cannot be supplied directly by the bloodstream because a network of blood capillaries within the lens, cornea and vitreous body would cloud the “view”. The task is therefore taken over by the aqueous humor, in which the proteins, hyaluronic acid, ascorbic acid and other substances necessary for the supply are dissolved as electrolytes. Ascorbic acid is of particular importance because vitamin C is a particularly effective antioxidant that counteracts oxidative damage caused by UV radiation and can thus prevent clouding in the cornea and lens. Vitamin C in the aqueous humor of the eye thus corresponds to a certain extent to “built-in sunglasses.”
Diseases
One of the most common diseases that can be associated with malfunction of the chambers of the eye is glaucoma, also known as glaucoma.One of several high-risk factors for the development of glaucoma is increased intraocular pressure. The increased intraocular pressure can occur when the trabecular meshwork in the anterior chamber of the eye is restricted in its function and cannot drain off enough aqueous humor. If the production of aqueous humor in the ciliary bodies in the posterior chamber of the eye is unchecked, a kind of congestion occurs in the chambers of the eye, which can cause the development of glaucoma. Glaucoma leads to gradual destruction of the optic nerve head, causing visual field loss. Glaucoma is one of the most common causes of blindness worldwide. Glaucoma is mainly caused by an imbalance between blood flow to the optic nerve and intraocular pressure. In the presence of circulatory disorders of the optic nerve, even normal intraocular pressure can trigger the disease. Loss of aqueous humor due to injury or after surgery can be similarly problematic. If the loss is not compensated, swelling of the choroid associated with significant visual disturbances occurs. If the lens capsule is mechanically damaged, aqueous humor may enter the lens, causing swelling of the lens cortex and making accommodation of the lens difficult.