Vitreous body

A clear gel fills your eye. It is like soft jelly. This gel helps your eye stay round. It sits behind the lens. It is mostly made of water. Most of it is water, but it also has salts and sugars. The gel is thicker near the edges. It is more like a liquid in the middle. As people get older, the gel can change. It may turn into a liquid. This can make small spots float in your vision. These spots are called floaters.

A clear gel fills your eye. This gel is called the vitreous body. It sits between the lens and the retina. The retina is the part of the eye that sees. The gel helps the eye keep its round shape. It makes up four-fifths of the eyeball's volume.

The gel is mostly water. In fact, it is 98 to 99 percent water. It also has salts, sugars, and proteins. It also has collagen. Collagen is a type of fiber that gives things strength. The gel is thick like jelly near the edges. It is more like a liquid in the center.

As people get older, the gel changes. The center may turn into a liquid. This is called syneresis. The gel may also pull away from the retina. This is called a vitreous detachment. This can make small spots float in your vision. We call these spots floaters. They are usually not harmful.

The vitreous body is a clear, jelly-like substance inside your eye. Its name comes from a word that means "glass-like." This gel fills the large space between your lens and your retina. The retina is the layer at the back of the eye that helps you see. This gel is very important because it helps the eyeball keep its round shape. It actually makes up about four-fifths of the total volume of the eyeball.

This gel works in a very specific way to support the eye. It is not the same thickness everywhere inside the eye. Near the edges, it is thick and gel-like. Near the center, it is much more like a liquid. A layer called the vitreous membrane surrounds the gel to separate it from other parts. Tiny fibers called collagen attach the gel to important spots like the optic nerve and the macula. The macula is the part of the retina that helps you see fine details.

Scientists have studied how this substance changes as we grow up. At birth, the vitreous is one solid, smooth mass. As people enter adolescence, the gel starts to form thin, sheet-like paths called tracts. These include the retrolental tract and the coronary tract. As adults age, these paths become even more clear and curvy. Eventually, the center of the gel may turn into a liquid. This change is called syneresis, and it can cause small spots to float in your vision.

There are many interesting facts about what makes up this gel. It is mostly water, containing about 98 to 99 percent water. It also contains salts like sodium and potassium. Other parts include sugars like glucose and proteins like collagen. In a typical adult, the volume of this gel is about 4 mL. However, this can change depending on the person. People with highly myopic eyes, which are nearsighted, may have more than 10 mL of gel.

Understanding the vitreous can even help experts after someone has passed away. After death, the vitreous resists breaking down longer than many other body fluids. The amount of potassium in the gel rises at a very steady speed. This allows experts to estimate how much time has passed since death. Because the gel changes slowly, it is a good choice for testing levels of glucose. This makes it a useful tool for science and forensic work.

The vitreous body is a clear, gelatinous mass located inside the eye. Its name comes from the Latin word for glass-like. This substance fills the vitreous chamber, which is the space between the lens and the retina. It is a vital part of the vertebrate eye because it helps maintain the eye's spherical shape. The vitreous body makes up about four-fifths of the total volume of the eyeball. While often called the vitreous humor, it is distinct from the aqueous humor found near the cornea.

The structure of the vitreous is not uniform throughout the eye. It is a transparent, colorless gel that is thicker near the edges and more liquid-like near the center. A layer of collagen called the vitreous membrane, or hyaloid membrane, surrounds the mass. This membrane separates the vitreous from the rest of the eye. The gel is anchored to several specific anatomical landmarks. Collagen fibrils attach the vitreous to the optic nerve disc and the ora serrata. It also attaches firmly to the lens capsule, retinal vessels, and the macula. The macula is the specific area of the retina responsible for central vision and fine detail.

There are many complex anatomical features within and around the vitreous. For example, Cloquet's canal is a 1–2 mm wide canal that runs in an S-shape through the vitreous. It connects the space of Martegiani to the space of Berger. Another feature is the Wieger-band, which is a circular thickening of the vitreous about 8–9 mm in diameter. This band helps delineate the patella fossa, a shallow area where the lens rests. Other landmarks include Berger's space and the space of Erggelet. These structures define the precise layout of the posterior segment of the eye.

The composition of the vitreous is mostly water, making up 98% to 99% of its volume. It contains a variety of salts, sugars, and proteins to maintain its properties. For instance, it contains sodium at a mean concentration of 146.7 mmol/L and potassium at 5.73 mmol/L. It also includes glucose, which averages 2.97 mmol/L. The structural integrity comes from a network of collagen type II fibrils and a substance called hyaluronan. Specialized cells called phagocytes remove cellular debris, while hyalocytes manage the turnover of hyaluronan. This chemical makeup gives the vitreous a viscosity two to four times that of water.

As humans grow, the vitreous undergoes significant developmental changes. At birth, the vitreous is a homogenous mass with a finely striated pattern. By adolescence, the vitreous cortex becomes denser and forms thin, sheet-like condensations called vitreous tracts. These include the retrolental tract, the coronary tract, the median tract, and the preretinal tract. As adults age, the center of the gel may undergo syneresis, which is a process of liquefaction. During this time, the gel volume decreases while the liquid volume increases. This can cause collagen fibers to clump together due to reduced electrical charges.

Changes in the vitreous can lead to specific visual experiences or medical conditions. When the gel liquefies, organic clusters can float freely, creating what are known as floaters. These appear as spots or strands in a person's visual field. If the vitreous pulls away from the retina, it is called a vitreous detachment. This is more common in people with myopia, or nearsightedness. In highly myopic eyes, the axial length is increased, which can lead to a vitreous volume exceeding 9–10 mL. This is much larger than the average adult volume of approximately 4 mL.

Beyond biology, the vitreous has important applications in forensic science. After death, the vitreous body resists putrefaction longer than most other body fluids. The concentration of potassium in the vitreous rises at a very predictable rate after death. Scientists use this steady increase to estimate the post-mortem interval, or the time since death. Because the exchange of substances between the blood and the vitreous is very slow, it is an excellent medium for analysis. Experts may test the vitreous for glucose levels or other substances that might degrade quickly in the general circulation.