Term
| What happens to vitreous over time? |
|
Definition
| liquefaction; it gets less stiff and more watery over time |
|
|
Term
| What is asteroid hyalosis? |
|
Definition
| aggregates in the vitreous; usually does not affect vision |
|
|
Term
| What is the difficulty induced by asteroid hyalosis? |
|
Definition
| inability to view retina with BIO due to obstruction |
|
|
Term
| What is synchysis scintillans? |
|
Definition
| an aggregation in the vitreous that DOES affect vision. Cholesterol/iron deposits due to chronic inflammation, trauma |
|
|
Term
| What % of vitreous is water? |
|
Definition
|
|
Term
| Is the vitreous cellular or acellular? |
|
Definition
|
|
Term
| What is found in vitreous extracellular matrix? |
|
Definition
| GAGs (charged carbohydrates such as hyaluronan) |
|
|
Term
| What is the mechanical purpose of the extracellular matrix? |
|
Definition
| Gives shape, strength, flexibility, resistance |
|
|
Term
| What type of collagen is primarily found in the vitreous? |
|
Definition
| Collagen Type 2 is most abundant, 60-75% |
|
|
Term
| What is a precursor to type II collagen? |
|
Definition
|
|
Term
|
Definition
| premature viteous degeneration and nuclear sclerotic cataract |
|
|
Term
| How many types of collagen are found in the vitreous? |
|
Definition
| 27, including II, IX, and V/XI |
|
|
Term
| Where is a small amount of collagen synthesized for the vitreous? |
|
Definition
|
|
Term
| What is the structure of vitreal collagen? |
|
Definition
triple helical
Every third AA is Gly: Gly-X-Y |
|
|
Term
| What % of vitreal collagen is type IX? |
|
Definition
|
|
Term
| What is the structure of type IX collagen? |
|
Definition
| a heterotrimer (alpha 1-3) |
|
|
Term
| What co-assembles with Type II collagen to form the vitreal core? |
|
Definition
|
|
Term
|
Definition
| non-collagenous glycoprotein |
|
|
Term
| What do glycosaminoglycans and proteoglycans cause in the vitreous? |
|
Definition
|
|
