The eye in systemic disease (incomplete)

Question 1

Where is the visual cortex found?

Answer 1

Occipital lobe

Question 2

What are the two most important clinical features which suggest neuro-ophthalmic disease?

Answer 2

Eye movement defects

Visual defects

Question 3

What symptom might a patient with eye movement defects describe?

Answer 3

Double vision

Question 4

What are the causes of neuro-ophthalmic disease?

Answer 4

Vascular disease
Space occupying lesions
Trauma
Demyelination
Inflammation/infection
Congenital

Question 5

What is the most common cause of neuro-ophthalmic disease?

Answer 5

Vascular

Question 6

How is suspected neuro-ophthalmic disease investigated?

Answer 6

Examination (ophtha + neuro)
Blood tests
MRI

Question 7

What memory aid can be used to remember the cranial nerves supplying the eye?

Answer 7

LR6 (lateral rectus VI)
SO4 (superior oblique IV)
AO3 (all others III)

Question 8

What does supra-nuclear refer to with respect to the brain?

Answer 8

Within the brain lobes (e.g supra-nuclear pathology)

Question 9

What does intra-nuclear refer to with respect to the brain)

Answer 9

Between nerve nuclei

Question 10

Which muscles control intorsion and extorsion?

Answer 10

Inferior and superior oblique

Question 11

What muscle(s) is paralysed in a sixth nerve palsy?

Answer 11

Lateral rectus

Question 12

What type of squint does a patient with sixth nerve palsy have? Why?

Answer 12

Esotropic (convergent)

The lateral rectus muscle is cannot perform abduction

Question 13

What are the causes of sixth nerve palsy?

Answer 13

Microvascular (hypertension, diabetes)
Raised ICP
Tumour
Congenital

Question 14

Microvascular causes of sixth nerve palsy usually resolve within a couple of months. T/F

Answer 14

True

Question 15

How will sixth nerve palsy due to raised ICP present?

Answer 15

Sudden onset eye movement defect/double vision

Headache

Question 16

Why does raised ICP cause compression of the sixth cranial nerve?

Answer 16

It runs over the petrous part of the temporal bone

Question 17

Is papilloedema associated with sixth nerve palsy bilateral?

Answer 17

Yep

Question 18

What is the most common cause of sixth nerve palsy?

Answer 18

Microvascular (2nd is raised ICP)

Question 19

Which muscle(s) is paralysed in fourth cranial nerve palsy?

Answer 19

Superior oblique

Question 20

Which movements does the superior oblique carry out?

Answer 20

Intorsion
Depression in adduction
Abduction (weak)

Question 21

Which direction will an eye be looking with fourth nerve palsy?

Answer 21

Up and out

Question 22

What sign will a patient with fourth nerve palsy characteristically have? Why?

Answer 22

Tilted head

Compensates for weak intorsion

Question 23

What are the clinical signs of bilateral fourth nerve palsy?

Answer 23

Chin depressed

Question 24

What is the cause of bilateral fourth nerve palsy? Why?

Answer 24

Head trauma (closed)
Long intracranial course and thin easily stretched nerve

Question 25

What are the causes of fourth nerve palsy? Which is most common?

Answer 25

Congenital (common) Microvascular Tumour Head trauma

Question 26

Which is the least common cranial nerve palsy with reference to the nerves supplying eye movments?

Answer 26

Oculomotor (III) nerve palsy

Question 27

How does an eye with III nerve palsy appear?

Answer 27

Down and out Ptosis Mydriasis

Question 28

Which muscles are affected in III nerve palsy?

Answer 28

``` Inferior oblique Medial rectus Superior rectus Inferior rectus Sphincter pupillae Levator palpebrae superioris ```

Question 29

What are the causes of III nerve palsy?

Answer 29

``` Microvascular Tumour Aneurysm Multiple sclerosis Congenital ```

Question 30

What will be the cause of a painful III nerve palsy?

Answer 30

Aneurysm

Question 31

Do microvascular causes of III nerve palsy cause mydriasis? Do aneurysms?

Answer 31

Nah | Always

Question 32

What is inter-nuclear opthalmoplegia?

Answer 32

Impaired horizontal eye movement (weak adduction of affected eye and abduction nystagmus of unaffected eye)

Question 33

What is the most common cause of inter-nuclear opthalmoplegia?

Answer 33

Multiple sclerosis | 2nd is vascular

Question 34

Working inter-nuclear pathways ensure that both eyes work in synchrony. T/F

Answer 34

True!

Question 35

Inter-nuclear opthalmoplegia arises from problems within which part of the brainstem?

Answer 35

Medial longitudinal fasciculus

Question 36

What is demyelination?

Answer 36

Damage to myelin insulator sheath surrounding nerves (known as white matter change)

Question 37

Describe the optic pathway

Answer 37

``` Optic nerve --> Optic chiasm --> Optic tract --> Optic radiation --> Visual cortex ```

Question 38

What are the causes of pathology within the optic pathway?

Answer 38

Vascular (cerebrovascular accident) Space occupying lesion Demyelination (multiple sclerosis) Trauma (surgical)

Question 39

Pathology with the left optic nerve will result in which visual field defect?

Answer 39

Complete loss of vision in left eye | Horizontal superior OR inferior loss of vision in left eye

Question 40

Pathology affecting the optic chiasm will result in which visual field defect?

Answer 40

Bitemporal hemianopsia

Question 41

Pathology affecting the left optic tract will result in which visual field defect?

Answer 41

Right sided hemianopsia

Question 42

Pathology affecting the occipital cortex will result in which visual field defect?

Answer 42

Homogenous hemianopsia

Question 43

Pathology affecting one of the optic radiations will result in which visual field defect?

Answer 43

Quadranopsia

Question 44

List pathologies which affect the optic nerve?

Answer 44

Ischaemic optic neuropathy Optic neuritis Tumours

Question 45

What is the most common cause of optic neuritis?

Answer 45

Multiple sclerosis

Question 46

What is optic neuritis?

Answer 46

Inflammation of the optic nerve

Question 47

List three tumours that can affect the optic nerve

Answer 47

Meningioma Glioma Haemangioma

Question 48

How does optic neuritis present?

Answer 48

``` Progressive visual loss Unilateral Pain behind eye exacerbated by movement Colour desaturation Central scotoma ```

Question 49

How is optic neuritis managed?

Answer 49

Self resolving over weeks/months

Question 50

What might be seen on fundoscopy following optic neuritis?

Answer 50

Optic atrophy (pale, featureless disc)

Question 51

Haemangioma can cause which ocular symptoms? What is the most common cause?

Answer 51

Unilateral proptosis Optic nerve compression (+ decreased vision) Extraocular muscle restriction (+ eye movement defect --> diplopia) Congenital

Question 52

Which pathologies affect the optic chiasm? Which of these affect children?

Answer 52

Pituitary tumour Craniopharyngioma (children) Meningioma

Question 53

How are visual defects caused by pituitary tumours managed?

Answer 53

Removal of tumour usually restores vision

Question 54

Which pathologies affect the optic tracts + radiations?

Answer 54

Tumours Demyelination (multiple sclerosis) Vascular abnormalities (AV malformation)

Question 55

With regards to defects within the optic tracts/radiations, is the macula spared?

Answer 55

Nope

Question 56

Can optic tract/radiation pathologies cause incongruous defects?

Answer 56

Yes!

Question 57

Which pathologies affect the occipital cortex?

Answer 57

``` Vascular disease (cerebrovascular accident) Demyelination (multiple sclerosis) ```

Question 58

Do pathologies affecting the occipital cortex result in macular sparing?

Answer 58

Yes!

Question 59

Can occipital cortex pathologies cause incongruous defects?

Answer 59

No - tend to be congruous

Question 60

A ring enhancing lesion on MRI tends to be characteristic of what?

Answer 60

Abscess (TB, parasites, chronic bacterial infection)

Question 61

Over which age is vascular disease the most common aetiology (in general) for neuro-opthalmic disease?

Answer 61

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