Lec 8 Flashcards Preview

PPO4 Lec 7-14 > Lec 8 > Flashcards

Flashcards in Lec 8 Deck (24)
Loading flashcards...
1

Where is aq humor produced?

CB epith

2

What enzymes control aq humorproduction?

Carbonic anhydrase, Na/K-dependent ATPase

3

Describe: conventional route of aq humor outflow

aq humor passes through TM into Schlemm's canal. Exits through collector channels into venous system; 70%+ of outflow

4

Describe: Unconventional route of aq humor outflow

Aq humor passes through uvealscleral pathway: through iris root uveal meshwork and anterior face of ciliary muscle --> through suprachoroidal space and out through slera; 30% or less of outflow

5

What is the most significant factor in the etiology of increased IOP?

interference with aqueous outflow

6

T/F: Prostaglandins increase outflow; Carbonic anhydrase inhibit production of aq humor

True

7

What % of pts dev glauc despite normal IOP?

30%

8

What is the diameter of the circular zone of applanation?

3.06 mm

9

What is the area of applanation?

7.3542 mm^2

10

Applanation tonometry has what standard dev of error?

+/- 0.5 mm Hg

11

What assumptions did Hans Goldmann make when devising his tonometer?

avg corneal thickness of 20 microns, resistance to deformation is cancelled out by surface tension generated when the area applanated has a diameter of 3.06mm

12

GAT: 1 g of force needed to flatten an an area equal to what? which means the diameter is what?

7.3542 mm^2, 3.06 mm

13

What are indications for punctal occlusion?

Preg, very young, HTN, when using multiple drops (so pt doesn't taste it), very dark brown eyes

14

Drops have been instilled. What happens every time a pt blinks?

meds go into the lac canal/sac and increase systemic absorpton

15

Fluress vs Flurox. Which has benoxinate?

Fluress has benoxinate

16

What is the wetting agent in Fluress?

Povidome

17

How many degrees of separation are between the A & O (or red & white lines) of a tono probe?

43 deg

18

K readings: 40 @ 050, 42.50 @ 140. Where would you line up the Red line of the tono probe?

050

19

If you see limbal glow, have you made contact with the cornea?

Yes

20

Mires that are too thick will give an artificially ___ IOP. Mires that are too thin will give an artificially ____ IOP.

high, low

21

lateral motion of mires is caused by what phenomenon? When do you "read" the mires?

Pulsating mires; when interlocked at the highest point

22

What are cautions/contraindications for Contact Tono?

allergy to all anesthetics, pts with recurrent corneal erosion, Bullous keratopathy, Corneal hydrops (Keratoconus), corneal abrasions that aren't healed, signif corneal edema

23

What doesn't wash out with disinfection, but does wash out with water?

Hep B virus DNA

24

What is the single most effective means of avoiding the risk of transmitting or acquiiring infections during an eye exam?

hand washing
(CDC rec's immediately before and after contact with pt)