Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ophthalmology > Misaligned And Wobbly Eyes > Flashcards

Misaligned And Wobbly Eyes Flashcards

1
Q

What is strabismus?

A

Squint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is strabismus classified.

A

Infantile (concomitant)
Acquired (incomitant)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe infantile strabismus

A

Manifest (tropia)
Intermittent
Near
Concomitant - no limitation of movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe acquired strabismus

A

Latent (phoria)
Constant
Distance
Incomitant - limitation of movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 2 types of incomitant strabismus?

A

Paretic - nerve palsy
Restrictive - mechanical restriction to muscle eg. Thyroid, tumour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is esotropia?

A

Eye points inwards (convergent)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What muscle is not working in esotropia?

A

Lateral rectus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is exotropia?

A

Eye points outwards (divergent)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What muscle is not working in exotropia?

A

Medial rectus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is hypertropia?

A

Eye points upwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is hypotropia?

A

Eye points downwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What muscles are not working in hypertropia?

A

Inferior rectus
Superior oblique

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What muscles are not working in hypotropia?

A

Superior rectus
Inferior oblique

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Causes of incomitant strabismus (paretic)

A

Supranuclear - dorsal midbrain
Inter nuclear - INO
Nuclear/nerve - 3rd, 4th, 6th palsies
Neuromuscular - myasthenia
Myopathies/myositis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Causes of incomitant strabismus (restrictive)

A

Thyroid eye disease
Orbital mass
Orbital wall fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Summarise constant strabismus

A

Full eye movements
Typically early childhood
Only some have double vision
Thypically bemign
No investigations normally
Often glasses help, may need surgery

17
Q

Summarise incomitant strabismus

A

Limitation of eye movements
Acquired later in life
Typically will have diplopia
May be serious
Tend to need investigation
Prisms and surgery

18
Q

Describe the cover test for strabismus

A

used to determine if manifest strabismus (heterotropia) is present

  • ask patient to focus on an object in the distance
  • cover one eye and observe the other
  • no shift in fixation of uncovered eye = orthotropic (normal alignment)
  • shift in fixation = heterotropia

repeat on other eye

19
Q

Describe the cover-uncover/alternate cover test

A

used to differentiate if a misalignment is either a tropia or a phoria

if cover test shows no tropia, this test is to see if there is phoria (latent strabismus)

examiner occludes one eye for approximately 1-2 seconds, then quickly removes the occluder to restore binocular vision

then observe the previously occluded eye for refixation movement

if a phoria is present, this eye will move back to being orthotropic (straight-looking) to re-establish sensory fusion with the other eye

20
Q

How can you tell if a strabismus is incomitant?

A

incomitant = limitation of movement

test eye movements in all directions

21
Q

What is saccadic testing useful for?

A

(fast eye movements)
useful for:
- supranuclear/internuclear disorders
- spotting subtle paresis
- testing saccadic pathways

22
Q

How does a 3rd nerve palsy affect the eye? (incomitant)

A

ptosis
down and out pupil
dilated pupil
abduction intact

23
Q

How does a 4th nerve palsy affect the eye? (incomitant)

A

torsion (tilt)
compensatory head tilt
hypertropia
impaired depression (in adduction)

24
Q

How does a 6th nerve palsy affect the eye? (incomitant)

A

esotropia
reduced abduction
ipsilateral face turn

25
Q

What is amblyopia?

A

lazy eye
unilateral or bilateral decrease of vision, caused by abnormal vision development in childhood or infancy

26
Q

Amblyopia causes

A

refractive:
- high refractive error
- anisometropic
- astigmatic

strabismic

sensory deprivation

27
Q

When is normal visual development mature by?

A

7 years old

28
Q

Amblyopia management

A

manage cause of sensory deprivation
glasses
patching or atropine penalisation
align eyes (squint surgery)

29
Q

Causes of abnormal red reflex

A

ethnic variation
high refractive error
squint
corneal scar/clouding
uveitis
pupillary membrane
cataract
PHPV
retinoblastoma
coloboma
toxoplasma/toxocara

30
Q

What is the name for lack of red reflex?

A

leucocoria

31
Q

What is nystagmus?

A

involuntary, repetitive to and fro movements of the eye

32
Q

Causes of nystagmus

A

infantile onset (<6mo):
- idiopathic
- albinism
- structural eye abnormality
- rod/cone abnormality

fusion maldevelopment (squint)

acquired (often neurological):
- CNS/vestibular disease
- drugs

33
Q

Red flags nystagmus

A

acquired onset >4mo
normal eyes
oscillopsia (‘world shaking’)
vertical/torsional
other neurological signs/symptoms

Ophthalmology (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions