Abnormal pupils

Question 1

Horner’s syndrome signs on examination

Answer 1

Face: PEAS
Partial ptosis (superior tarsal muscle)
Enophthalmos
Anhydrosis
Small pupil
NO ophthalmoplegia
Neck scars:
Central lines
Carotid endarterectomy
Hands:
Complete claw hand + intrinsic hand weakness
Reduced or absent sensation in T1

Question 2

Completion of a Horner’s examination

Answer 2

Cerebellar exam

CNS and PNS

Question 3

Differential diagnosis for Horner’s

Answer 3

Central:
Multiple sclerosis
Lateral medullary syndrome
Pre-ganglionic (neck):
Pancoast's tumour (T1 nerve root)
Trauma from central venous access insertion or carotid endarterectomy
Post-ganglionic:
Cavernous sinus thrombosis - usually secondary to spreading facial infection via the ophthalmic veins; would include CN 3,4,5,6 palsies.

Question 4

Features of oculomotor nerve palsy

Answer 4

Complete ptosis (levator palpebrae superioris)
Eye points down and out: unopposed superior oblique and left rectus
Dilated pupil, doesn't react to light (unless spared in early medical oculomotor palsy)
Ophthalmoplegia and diplopia

Question 5

Medical versus surgical oculomotor nerve palsy

Answer 5

Parasympathetic fibres originate in Edinger-Westphal nucleus and run on periphery of the oculomotor nerve.
They receive rich blood supply from the external plial vessels.
These fibres are affected late in ischaemic causes (medical) but early in compression (surgical).

Question 6

Causes of medical oculomotor nerve palsy

Answer 6

MMMM
Mononeuritis, e.g. DM
Multiple sclerosis
Midbrain infarction
Migraine

Question 7

Causes of surgical oculomotor nerve palsy

Answer 7

Raised ICP (transtentorial herniation compresses uncus)
Cavernous sinus thrombosis
Posterior communicating artery aneurysm

Question 8

Describe Holmes-Adie pupil

Answer 8

AKA myotonic pupil
Dilated pupil that has no response to light and sluggish response to accommodation
Reduced or absent ankle and knee jerks.
Benign condition more common in young females.

Question 9

Features of Argyll Robertson pupil

Answer 9

Small, irregular pupils
Accommodate but doesn’t react to light
Atrophied and depigmented iris

Question 10

Extra tests for Argyll Robertson pupil

Answer 10

Offer to look for sensory ataxia (Romberg’s test): tabes dorsalis
Dipstick urine: glucose (DM)

Question 11

Causes of Argyll Robertson pupil

Answer 11

Quaternary syphilis

DM

Question 12

Synonym for relative afferent pupillary defect (RAPD)

Answer 12

Marcus Gunn pupil

Question 13

Features of RAPD

Answer 13

Minor constriction to direct light

Dilatation on moving light from normal to abnormal eye

Question 14

Features of optic atrophy

Answer 14

Reduced visual acuity
Reduced colour vision: especially red desaturation
Central scotoma
Pale optic disc
RAPD

Question 15

Causes of optic atrophy

Answer 15

Commonest: multiple sclerosis, glaucoma
CAC VISION
Congenital
Alcohol and other toxins
Compression
Vascular (DM, GCA, thromboembolic)
Inflammatory: optic neuritis (MS, Devic's, DM)
Sarcoid
Infection (VZV, TB, syphilis)
Oedema (papilloedema)
Neoplastic infiltration: lymphoma, leukaemia

Question 16

Congenital causes of optic atrophy

Answer 16

Leber’s hereditary optic neuropathy (mitochondrial, onset in 20s, presents with attacks of acute visual loss)
CMT
Friedrich’s ataxia
DIDMOAD

Question 17

Toxins causing optic atrophy

Answer 17

Alcohol
Ethambutol
Lead
B12 deficiency

Question 18

Compressive causes of optic atrophy

Answer 18

Neoplasia: optic glioma, pituitary adenoma
Glaucoma
Paget’s