Week 9: The Vitreous Body

Question 1

What is the vitreous body?

Answer 1

-A transparent gel between the lens and retina.

Question 2

Extra info

Answer 2

> RI of 1.33
Viscosity 2-4 times that of water
Made up of 98% water, some salts, soluble proteins and collagen fibres (8-12nm in diameter) that entrap hyaluronic acid

Question 3

What is the lenticular/hyaloid fossa? (NEED TO EDIT IDK THIS)

Need to write the vitreous anatomy

Answer 3

Saucer shaped gap between lens

Question 4

Where is the vitreous attachment?

Answer 4

> Firmly attached at:
- The lens
- The ciliary epithelium at the pars plana (flat part of ciliary body)
- The neural retina
- at ora serrata
- margin of the optic disc
Loosely attached elsewhere – thus susceptible to detachment

Question 5

What is the functions of the vitreous?

Answer 5

> Transmits light and contributes to the dioptric power of the eye
Supports the lens
Assists in holding the neural retina on to the pigment epithelium (holds retina down)

Question 6

What happens, due to ageing, to the vitreous?

Answer 6

> From age 40 years onwards vitreous becomes less viscous (syneresis)
Weakens connection with neural retina
Can lead to vitreous detachment which will predispose to retinal detachment

> Collagen fibres in the matrix can come out of suspension and form a precipitate, these are opaque and interfere with vision (floaters)