Eye Movement Defects

Question 1

what is the first manifestation of a squint? (eyes look in different directions)

Answer 1

diplopia

Question 2

diagnosis of squint

Answer 2

cover test- need a pen torch, occluder and near (1/3m) and distant (6m) targets

Question 3

should you wear glasses in cover test?

Answer 3

yes

Question 4

four types of tropias

Answer 4

1. esotropia
2. exotropia
3. hypertropia
4. hypotropia

Question 5

what is esotropia?

Answer 5

outward movement of the eye (convergent)

Question 6

what is exotropia?

Answer 6

inward movement of the eye (divergent)

Question 7

what is a hypertropia?

Answer 7

downward movement of the eye

Question 8

what is hypotropia?

Answer 8

upward movement of the eye

Question 9

what does ocular motility assess?

Answer 9

muscle pairs

Question 10

what do you need in an ocular motility assessment?

Answer 10

pen torch

9 positions

Question 11

should the patient wear their glasses in an ocular motility test?

Answer 11

no

Question 12

result in ocular motility test if weakness in muscle/muscle pairs

Answer 12

some sclera still seen

Question 13

three examples of eye movement defects

Answer 13

1. VI nerve palsy
2. IV nerve palsy
3. III nerve palsy

Question 14

what causes VI nerve palsy?

Answer 14

LR cannot abduct fully

Question 15

presentation of VI nerve palsy?

Answer 15

some sclera still visible when looking outwards

horizontal diplopia

Question 16

causes of VI nerve palsy?

Answer 16

raised ICP
tumour
congenital

Question 17

how does raised pressure affect the CNVI?

Answer 17

nerve rests on temporal bone therefore can be compressed

Question 18

what is IV nerve palsy?

Answer 18

SO cannot depress the eye

Question 19

presentation of IV nerve palsy?

Answer 19

eye drifts when looking ahead
intorsion
depression in adduction
weak abduction
hypertropia
diplopia is vertical
head tilt

Question 20

causes of IV nerve palsy?

Answer 20

congenital decompensated
microvascular
tumour
bilateral in closed head trauma (shaking brain in cranial cavity can stretch the 4th nerve which is very thin)

Question 21

what is III nerve palsy?

Answer 21

MR, IR, SR, IO, sphincter pupillae and levator palpebrae superioris are affected

Question 22

presentation of III nerve palsy?

Answer 22

down and out
dilated
divergent strabismus
ptosis
diplopia that is horizontal and vertical
exotropia with hypotropia

Question 23

causes of III nerve palsy?

Answer 23

expanding aneurysm (EMERGENCY)
tumour
MS
congenital

Question 24

what is inter-nuclear ophthalmoplegia?

Answer 24

eyes work together due to connection between the nuclei of the medial longitudinal fasciculus and this is damaged

Question 25

causes of inter-nuclear ophthalmoplegia?

Answer 25

MS (demyelination)
vascular
mass

Question 26

presentation of inter-nuclear ophthalmoplegia?

Answer 26

failure to adduct