Eye Movements and Axes

Question 1

what are the different axes in terms of eye movements

Answer 1

vertical, transverse and AP axes

Question 2

what type of movement occurs on the vertical axes, and in relation to what

Answer 2

abduction/adduction, in relation to direction of gaze

Question 3

what type of movement occurs on the transverse axes, and in relation to what

Answer 3

elevation/depression, in relation to direction of gaze

Question 4

what type of movement occurs on the AP axes, and in relation to what

Answer 4

intorsion/extorsion, in relation to superior pole of eyeball

Question 5

how many movements do each of the eye muscles have

Answer 5

each have primary movement, and all have secondary as well except medial and lateral rectus

Question 6

describe what you need to do in order to test eye movement and muscles properly

Answer 6

have to line up direction of gaze to the plane of the muscle being tested in order to isolate movements
(except lateral and medial rectus as they only have one movement)

Question 7

what is the only movement lateral rectus is capable of, and what cranial nerve is it innervated by

Answer 7

can only abduct eyeball, CN VI(Abducent)

Question 8

what extraocular muscles are the lateral rectus responsible for brining line of gaze to same plane as the muscle for testing of movements

Answer 8

superior rectus and inferior rectus

Question 9

what direction must gaze be looking in order to test movement of superior and inferior rectus

Answer 9

eye must be abducted

Question 10

when eye is in abduction, what is the only movement superior rectus is capable of, and what cranial nerve is it innervated by

Answer 10

can only elevate, by CN III(Oculomotor)

Question 11

when eye is in abduction, what is the only movement inferior rectus is capable of, and what cranial nerve is it innervated by

Answer 11

can only depress, by CN III(Oculomotor)

Question 12

what is the only movement medial rectus is capable of, and what cranial nerve is it innervated by

Answer 12

can only adduct eyeball, CN III(Oculomotor)

Question 13

what extraocular muscles are the medial rectus responsible for bringing the line of gaze to same plane as the muscle for testing

Answer 13

superior oblique and inferior oblique muscles

Question 14

what direction must gaze be looking in order for superior and inferior oblique extraocular muscles to be tested

Answer 14

eye must be adducted

Question 15

when eye in adduction what is the only movement inferior oblique is capable of

Answer 15

can only elevate, by CN III(Oculomotor)

Question 16

when eye in adduction what is the only movement superior oblique is capable of

Answer 16

can only depress, by CN IV(Trochlear)

Question 17

what extraocular muscles are responsible for pure elevation of the eye
(ie elevation when looking straight ahead)

Answer 17

superior rectus and inferior oblique

Question 18

what extraocular muscles are responsible for pure depression of the eye
(ie depression when looking straight ahead)

Answer 18

inferior rectus and superior oblique