horners syndrome

Question 1

sx

Answer 1

ptosis, meiosis with or without anhydrosis

Question 2

cx

Answer 2

due to an interruption of the sympathetic nerve supply to the eye and can be classified into pre-ganglion causes, post ganglionic causes and central causes.

Pancoast tumour (affecting sympathetic nerve supply)
Stroke
Carotid artery dissection (Red flag: neck pain)

Question 3

carotid artery dissection causes what reg flag sx

Answer 3

neck pain

Question 4

what drug determines whether horners syndrome is pre or post ganglionic

Answer 4

Hydroxyamphetamine

Question 5

moa of hydroxyamphetamine in horners syndrome

Answer 5

will cause intact symapthetic post gnaglionic neurones to relase NA and cause dialtion of the pupil indicating lesion is pre ganglionic

in post so no effect on pupil

One hour after instillation of 1% hydroxyamphetamine eye drops dilation of both pupils indicate a lesion of the 1st or 2nd order neuron. If the smaller pupil fails to dilate it indicates a lesion of the 3rd order or postganglionic neuron.

Question 6

what drug confirms horners and how does it work

Answer 6

apraclonidine
nroaml pupil bind to week alpha 1 receptors and has little affect
horners - cause dialtion of pupil and reoslution of ptosis
cocaine eye drops alternative