MT 1

Question 1

When seeing with motion during ret:

Answer 1

“Down with the ship,” add + (turn knob down)

Question 2

When seeing against motion during ret:

Answer 2

“Up against the wall.” add - (turn knob up)

Question 3

Torsional eye movements

Answer 3

intorstion: top of eye rotates toward nose
extorstion: top of eye rotates away from nose

Question 4

Disconjugate vergence

Answer 4

convergence: toward nose
divergence: away from nose

Question 5

What is goal of versions?

Answer 5

Move eyes in 6 cardinal directions, or determine muscle restriction

Question 6

Cranial nerves related to EOMs

Answer 6

III- oculomotor (all others)
IV- trochlear (SO)
VI- abducens (LR)

Question 7

Hering’s law

Answer 7

TWO eyes, contralateral synergists are equally innervated

Question 8

Sherrington’s law

Answer 8

ONE eye, contraction accompanied by proportional relaxation of antagonist

Question 9

Recording abnormal EOM’s

Answer 9

“limitation of gaze”

Question 10

NPC

Answer 10

distance where convergence breaks down

Question 11

NPC Pd calculation

Answer 11

(IPD x 10) / (NPC break in cm + 2.7)
ex. IPD 60, NPC 5 cm
Pd = 78

Question 12

T/F: HBRx worn during NPC

Answer 12

True (near Rx required)

Question 13

Pinhole accomplishes:

Answer 13

increased depth of field/focus, reduced blur

***reduced brightness

Question 14

Snellen notation:

Answer 14

Numerator: testing Dx
Denominator: letter size (Dx letter subtends 5’ arc)

Question 15

Progression after big E:

Answer 15

CF > HM > LP with projection > LP > NLP

Question 16

Which is better VA?
A. 0.40/2.0M
B. 0.40/1.0M

Answer 16

B

Question 17

Which is better VA?
A. 0.40/0.8M
B. 0.20/0.8M

Answer 17

A

Question 18

Which is better VA?
A. 0.40/1.2M
B. 0.30/0.8M

Answer 18

B

reciprocal of fraction is MAR number, lower MAR is better

Question 19

How much less is NPD on average than DPD?

Answer 19

~3 mm

Question 20

Myopia

Answer 20

Eye: too much + (long eyeball)

Image pt in front of retina, far pt closer than infinity

Question 21

Hyperopia

Answer 21

Eye: too much - (short eyeball)

Image pt behind retina, far pt beyond infinity

Question 22

Simple myopic astigmatism

Answer 22

One at retina, one in front of retina

Question 23

Simple hyperopic astig

Answer 23

One at retina, one behind retina

Question 24

Compound myopic astig

Answer 24

Both in front of retina

Question 25

Compound hyperopic astig

Answer 25

Both behind retina

Question 26

Mixed astig

Answer 26

One in front of retina, one behind

Question 27

Calculate height of letter (Optotype)

Answer 27

tan(5/60) = x/20 ft (20 ft x 304.8 mm)

in mm