Ophthalmology

Question 1

Lesion anterior to optic chiasm

Answer 1

unilateral field defect

Question 2

Lesion posterior to optic chiasm

Answer 2

Contralateral homonymous defect

Question 3

Defect at optic chiasm

Answer 3

Bitemporal defect

Question 4

More congrouous and symetrical defect

Answer 4

Closer to primary visual cortex in occipital lobe

Question 5

Homonymous hemianopia

Answer 5

Contralateral optic tract affected

Commonly caused by stroke/tumour

Question 6

Quadrantopia

Answer 6

Bilateral lesion, thus post chiasmal

Question 7

Bitemporal hemianopia

Answer 7

Lesion at optic chiasm

Usually neoplasia

Question 8

Pituitary tumour

Answer 8

Bitemporal superior quadrantanopia
Respects vertical but not horizontal midline
Can result in optic neuropathy

Question 9

Central field defect

Answer 9

Secondary to age-related macular degeneration/optic nerve disease
Symmetrical, subacute, progressive
Reduced colour vision and acuity

Question 10

Causes of diplopia

Answer 10

Displacement of globe in orbit (trauma, tumour, infection)
CN Palsy
Decompensated latent squint
Extraoccular muscle disease (MG)
Thyroid eye disease

Question 11

Amblyopia

Answer 11

Lazy eye

Acuity

Question 12

Causes of monocular diplopia

Answer 12

Corneal abnormality (scar)
Uncorrected refractive error
Cataract

Question 13

Causes of binocular diplopia

Answer 13

Motor nerves

Extraocular muscles

Question 14

Sign of CN III Palsy

Answer 14

Down and out gaze

Pupillary dilation

Question 15

Muscles innervated by CN III

Answer 15

Inferior oblique
Medial rectus
Superior rectus
Inferior rectus

Question 16

Muscles and action innervated by CN IV

Answer 16

Superior oblique

Causes internal rotation of eye mainly

Question 17

Muscles and action innervated by CN VI

Answer 17

Lateral rectus

Abduction of eye

Question 18

Causes of CN VI Palsy

Answer 18

Transient and benign in children

Adults: HT, DM, MS, malignancy, trauma, infection, raised ICP

Question 19

Causes of unilateral optic nerve swelling

Answer 19

Central retinal vein occlusion
Non arteritic anterior ischaemic neuropathy
Arteritic anterior ischaemic neuropathy
Papillitis
Neuroretinitis

Question 20

Central retinal vein occlusion

Answer 20

Common, unilateral severe visual impairment
Retinal haemorrhage
Hyperaemic swollen disc
Large retinal veins

Question 21

Non arteritic anterior ischaemic neuropathy

Answer 21

Occlusion of short posterior ciliary arteries
Infarction of head of optic nerve
Painful, monocular sudden loss of vision
Reduced acuity
Haemorrhages (splinter and flame)

Question 22

Arteritic anterior ischaemic neuropathy

Answer 22

Sudden, painful monocular loss of vision (Emergency)
Usually >50 YO
Linked to giant cell arteritis (jaw claudication, reduced acuity, non pulsatile tender temporal artery)
Swollen optic disc
RAPD
Flame haemorrhages and cotton wool spots

Question 23

Papillitis

Answer 23

Inflammation of optic nerve head

Question 24

Neuroretinitis

Answer 24

inflammation of optic nerve and papillary retina

Question 25

Causes of bilateral optic disc swelling

Answer 25

Intracranial mass lesion (high iCP)
Malignant HT
Optic disc drusen (calcification) causes pseudo papilloedema (asymptomatic)