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Flashcards in B12 Deck (164)
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1

For someone with glaucoma, is the AH flow in and out equal?

No

2

Is the uveoscleral pathway the minor or major route /pathway in AH outflow?

Minor

3

Describe how AH flows in the uveoscleral pathway

AH enters the connective tissue between the ciliary muscle bundles, through the suprachoroidal space, and out through the sclera

4

Is the uveoscleral outflow affected by IOP?

Nope

5

The outflow rate through the uveoscleral route tends to ____ with age

Decrease

6

What are the 3 layers of the TM?

-juxtancanalicular
-corneaoscleral
-uveal

7

The corneoscleral pathway is considered the ____ route

Major

8

Describe the flow of AH in the corneoscleral pathway

AH passes through the TM, across SC, into its lumen
and into draining collector channels, aqueous veins and episcleral veins

9

Is the corneoscleral pathway IOP independent or dependent?

dependent

10

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

1:1

11

When the aqueous outflow pump receives power from transient increases in IOP such as occur in systole of the cardiac cycle during blinking and during eye movement

Pumping model

12

In the corneoscleral pathway an increase of IOP causes drainage decrease or increase?

Increase

13

What will make schlemm's canal collapse on itself and obstruct into the venous system?

Constant, very high IOP

14

What 2 fluid compartments is the TM suspended between?

And are these at the same or different pressures?

Anterior chamber and schlemms canal

They have different pressures

15

What 5 things can cause AH outflow obstruction through occlusive angles?

-severe diabetes
-uveitis
-hyphema
-pseudoexfoliative glaucoma
-pigment dispersion glaucoma

16

In humans, ___% of the resistance to the AH outflow is localized to the TM, and ___% occurs beyond schlemm's canal

75% to TM
25% to SC

17

Can an injury to the TM cause an obstruction of AH outflow?

It sure can

18

What are the 3 long term influences on IOP?

-genetics
-gender
-refractive error

19

What are the 6 short term influences on IOP?

-diurnal
-postural variation
-lid and eye movement
-systemic conditions
-environmental conditions
-food and drugs

20

T/F: IOP is under hereditary influence

True

21

Are IOP's different between men and women in the ages of 20-40?

Nope, they are equal

22

In older age groups, do men or women have a increase in mean IOP?

Women

23

Myopic people have a ____ incidence of open angle glaucoma

Higher

24

T/F: there is a positive correlation between IOP and both axial length and increasing degrees of myopia

True

25

Does IOP change throughout the day?

Yep

26

When is the peak of IOP?

In the morning

27

T/F: IOP decreases changing from sitting to the supine position

False, it increases

28

Patient with systemic hypertension will have a greater IOP increases after ___ min in supine

15 minutes

29

Does blinking raise IOP?

Yes, by 10mmHg

30

How much does hard lid squeezing raise IOP?

As much as 90mmHg