Ophthalmology 7 - Pupil Disorders

Question 1

pupil constriction how

Answer 1

circular muscles in iris stimulated by parasympathetic nerves using ACh

fibres travel along oculomotor nerve

Question 2

pupil dilation how

Answer 2

dilator muscles around iris stimulated by sympathetic system using adrenaline

Question 3

irregular pupil cause

Answer 3

trauma to sphincter muscles e.g. from surgery

Question 4

anterior uveitis and mis shapen pupil

Answer 4

from adhesions

Question 5

acute angle closure glaucoma pupil shape change

Answer 5

ischaemic damage to iris muscles and abnormal shape (vertical oval)

Question 6

rubeosis iridis

Answer 6

neovasc of iris
distorts shape
usually diabetes

Question 7

coloboma

Answer 7

congential weird iris shape

Question 8

tadpole pupil

Answer 8

spasm in iris segment
temporary
migraine assoc

Question 9

myadriasis (dilated pupil) causes

Answer 9

third nerve palsy
Holmes-Adie syndrome
raised ICP 
congenital 
trauma 
stimulants 
anitcholinergics

Question 10

miosis causes (constricted pupil)

Answer 10

Horner's syndrome
cluster headaches
Argyll-Robertson (neurosyphilis)
Opiates
Nicotine 
Pilocarpine

Question 11

third nerve palsy

Answer 11

ptosis
dilated fixed pupil
divergent strabismus

strabismus = squint

Question 12

oculomotor nerve pathway

Answer 12

travels through cavernous sinus close to posterior communicating artery

Question 13

causes of third nerve palsy, pupil-sparing

Answer 13

diabetes
hypertension
ischaemia

Question 14

causes of third nerve palsy (complete)

Answer 14

idopathic
tumour
trauma
cavernous sinus thrombosis
posterior communicating artery aneurysm
raised ICP

Question 15

Horner syndrome

Answer 15

ptosis
miosis
anhydrosis

damage to sympathetic nervous system

may have sunken eye too

Question 16

central causes x 4 of Horner’s syndrome

Answer 16

stroke
MS
swelling
syringomyelia

Question 17

pre-ganglionic causes x4 Horner’s syndrome

Answer 17

tumour (Pancoast)
trauma
thyroidectomy
top rib (false rib extra)

Question 18

post ganglionic causes x 4 Horner’s syndrome

Answer 18

cartoid aneurysm
carotid dissection
cavernous sinus thrombosis
cluster headache

Question 19

explain why pre/post ganglion is relevant in Horner’s

Answer 19

ganglion is at base of neck

so pre ganglion will be affected by lower neck pathology, post will be above + near carotid

Question 20

anhydrosis patterns in Horner’s syndrome

Answer 20

central lesion - no seating in arm and trunk as well

pre gang - only in face

post gang - NONE

Question 21

testing for Horner syndrome

Answer 21

check no heterochromia (in which case may be congential )

cocaine eye drops - no pupil reaction, should dilate

0.1% adrenaline eye drops would dilate Horner’s but not other pupil

Question 22

Holmes Adie

Argyll Robertson pupil

Answer 22

HA pupil - unilateral dilated sluggish pupil
may be viral cause

AR pupil - neurosyphilis - constricted pupil that accommodates to focus but doesn’t react to light