A clear substance in the eye with a gel-like consistency is called the vitreous. Vitreous occupies at least two-third of your eye's space and the gel is conposed of 99% water, and the other 1% is made up of collagen and hyaluronic acid, which give the vitreous its gel-like consistency.
The main functions of vitreous are to:
The back surface of vitreous is in direct contact with the retina and the blood vessels which supple the retina. Mostly, the vitreous grows more liquid and separates with the retina. It then collapses into the central hollow part of the eye. It also makes up a posterior vitreous detachment (PVD) and occurs with normal ageing.
PVD causes floaters and flashes are difficult to distinguish and only an ophthalmologist or optometrist can diagnose it through an eye exam. The following symptoms should indicate an issue with your vitreous and you should get your eyes examined as soon as possible.
Floaters: These are defined as dark dark spots or objects "floating" in the field of vision. These floaters may represent an eye bleeding inside the eye, or torn retinal tissue, but usually they are the particles that have been in the vitreous all along. With ageing, the particles start floating and can be seen because the vitreous becomes more liquid. The brain fails to notice them when they are fixed in space in the more solid gel. People also describe floaters as "spots and dots," "a cloud of smoke," or a "swarm of bees."
Lighting Flashes: The vitreous tugging during eye movement generates lightning flashes. When a PVD occurs, there may initially be residual areas where the vitreous remains attached to the retina, causing these light flashes. People with this symptom also describe their experience as "a sparkle or twinkle," "a disco light," or "fireflies."
Decreased Vision: Decreased vision is not usually present, although vision can decrease secondary to bleeding inside the eye or retinal detachment.
If a person develops retinal detachment early on, their central vision may remain normal but some people may begin to note a "curtain, veil, or fog" that may increasingly blot out the peripheral vision, followed by loss of central vision.
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