The vitreous humor comprises a large portion of the eyeball. It is a clear gel that occupies the space behind the lens and before the retina at the back of the eye. Because the eye must process visual data, this liquid must be clear enough that light can easily pass through. Most of this humor consists of water as well as a lower amount of collagen, salt and sugar. This humor is a stagnant substance that is not served by any blood vessels and is not actively regenerated or replenished. It is a contrast to the aqueous humor, which fills the anterior chamber in front of the lens. If a substance enters the vitreous humor, it will remain suspended in the gel until it can be surgically removed. Typically, these substances include blood and other substances and are collectively referred to as floaters. If left alone, floaters can affect a person's field of vision. Problems with the vitreous humor include liquidation and detachment from the retina.