Aging Changes In The AC/vitreous/lacrimal System Flashcards Preview

Ocular Phys Block 12 > Aging Changes In The AC/vitreous/lacrimal System > Flashcards

Flashcards in Aging Changes In The AC/vitreous/lacrimal System Deck (38)
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1

An acute rise in EVP results in a _____ ratio of increase IOP

1:1

2

Conventional pathway

-Cornrealscleral outflow
-TM and SC (main structures)
-IOP dependent

3

Unconventional pathway

-uveoscleral outflow
-ciliary muscle bundle
-IOP independent

4

Factors affecting IOP

Peak int he morning
Corneal thickness
Steroid

5

Outflow obstruction

Occlusive angle
-diabetes, uveitis, hyphema, pseudoexfoliation glaucoma, pigment dispersion glaucoma

Injury to the TM
-Fuchs heterochromic iritis, glaucomatocyclitic crisis

6

Classic Goldman equation

An acute ride in EVP results in a 1:1 ratio of increase in IOP

7

Aging changes in anterior chamber

-reduced anterior chamber depth, cortical cataract has more effect on this change
-reduced uveoscleral outflow. Increase in amount of connective tissue in ciliary muscle
-accumulation of extracellualr matrix plaque in TM
-increased outflow resistance in the TM and SC

8

Vitreous function

Support
Diffuse barrier
Metabolic barrier
Transparency

9

Vitreous function: support

PVD; macular edema

10

Vitreous function: metabolic buffer

Reduce neovascularixation in retina
-neovascular glaucoma
-NSC

11

Vitreous function: transparency

-synchisis scintillations
-asteroid hyalosis

12

Aging change of the vitreous

The gel structure becomes more liquefied with aging

13

Breakdown of the vitreous gel and aggregation of collagen fibrils due to increase of liquid potion

Vitreous syneresis

14

What is the most common cause of pVD

Vitreous syneresis

15

Floaters

Aggregation of collagen fibrils

16

Where is the change of the gel of the vitreous most likely to happen with age

In the center

17

Mucus layer composition

Mucin

18

Mucus layer functions

-provides medium for aqueous
-cover epithelium
-trap debris and bacteria

19

Mucus layer sources

-goblet cells (primary)
-squamous cells of cornea and conj

20

Lipid layer composition

Meibomian oil

21

Functionsof lipid layer

Slow the evaporation of the awe opus layer

22

Vitreous compositions

Water
Collagen
HA
Vitreal cells
Vitamin C

23

Functions of lipid layer

Slow the evaporation of the aqueous layer

24

Sources of the lipid layer

-meibomian gland (primary)
-Zeiss and Moll

25

Composition of aqueous layer

-water
-electrolytes
-Na and CL (osmolarity)
-K and Ca (cornea epeothelium health)
-proteins

26

Functions of the aqueous layer

-provide protection
-buffering
-regulation cornea epithelium proliferation’s

27

Sources of the aqueous layer

Main lacrimal gland
Accessory lacrimal gland

28

Clinical evaluation for tear secretion

Schirmer 1
Schirmer II
Phenol red thread test
Meinscometry

29

Clinical evaluation of tear film stability

TBUT
Ocular protection index
Videokeratography
Tear turnover

30

Clinical evaluation of the tear film osmolarity

Tear film osmolarity
Tear ferining
Tear evaporation