Details of the vitreous body

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It is well-known that a human eye consists of several parts which have specific functions. As a clear white thing over the outside of the eye, cornea helps focus light entering the eye on the retina. Iris is a colored part which can adjust its size so as to control the amount of light the eye receives. Pupil is similar for most people and it is the opening in the middle of the eye. A single eye has many other parts, e.g. aqueous humor, lens, retina and vitreous humor. In particular, this article details various aspects of the vitreous humor, which is clear water-like stuff in the back of the eye.

Different cells in the vitreous humor

Produced by cells in the cilary body, vitreous is the colorless, transparent, gelatinous mass between the eye’s lens and the lining of the retina. Similar to egg white and blood plasma, vitreous contains several types of cells, each of which has their respective functions. Phagocytes in the vitreous are responsible for removing unwanted debris from the visual field. Hyalocytes of Balazs can reprocess Hyaluronic acid, which begins to disappear around the age of 50. Vitreous also contains sugars, salts, vitrosin, and a network of collagen type II fibers.

Vitreous is 98% water

Supported by a network of collagen and the negative charge of MPS Hyaluronic acid, water content of the vitreous is 98%, much higher than 75% of the lens. Vitreous is consistent because its viscosity is about 2 to 4 times more than pure water.

Touch points of between the vitreous and the retina

Vitreous keeps contact with the retina and helps it keep stationary by pressing against the choroid. In detail, vitreous sticks to the retina in three places: the optic nerve disc, the anterior border between the retina and the macula, and the tiny spot in the retina. All of these places are where the posterior vitreous detachment (PVD) commonly occurs. This is a relatively common ocular problem that the vitreous humor separates from the retina. And thus the balance between these two eye parts is disturbed.

Reasons for vitreous detachment

Vitreous detachment occurs when the vitreous is pulled off from the retina, which happens more frequently and at an earlier age to people with myopia. Vitreous detachment can also be caused by uveitis or inflammation. As people age, vitreous gradually liquefies and sometimes collapses, which is much more dangerous. What’s more, this liquefaction is beyond systemic medications. The reason is that these systemic medications require delivery to the blood supply but the vitreous is a closed system with no blood support.

The link between the vitreous humor and the aqueous humor

Replenished continuously, there is fluid in the aqueous humor at the front of the eye, which is different from the stagnant gel in the vitreous. As a result, cells, blood, or other inflammation by-products will stay in the vitreous once they have entered and require surgical removal.