5 pupils and ptosis

Question 1

Sympathetic pathway for iris:

Answer 1

1st neuron: hypothalamus > spinal cord > ciliospinal centre
2nd neuron: ciliospinal > lung apex > superior cervical ganglion (jaw(
3rd neuron: superior cervical g. > internal carotid > cavernous sinus > CN 5 V1 (ophthalmic) > long ciliary nerves > iris dilator

Question 2

Parasympathetic pathway for iris:

Answer 2

Afferent: Optic nerve > split at chiasm > optic track > split before LGN > pretectal nuclei > edinger-westphal nuclei.
Efferent: Edinger-westphal nuclei > CN 3 > ciliary ganglion > iris sphincter

Question 3

Para/sympathetic iris path for miosis/mydriasis:

Answer 3

Parasympathetic > miosis via sphincter muscle

Sympathetic > mydriasis via dilator muscle

Question 4

Pilocarpine pharmacology and DDX:

Answer 4

Muscarinic agonist for neuromuscular junction of sphincter, upregulates receptor number > hypersensitivity > constriction.
Dilute pilocarpine (0.5-0.15%) > tonic pupil constriction
Pilocarpine  (1-2%)  > no constriction in pharmacogically induced / constriction in third nerve palsy

Question 5

Horners testing with cocaine:

Answer 5

Cocaine hydrochloride (10%), blocks norepinephrine reuptake in presynaptic terminal 
Horners: 2 cocaine doses 5 mins apart. Normal redilation 45-60 mins, horners will fail to dilate from lack of norepinephtine relaease. Expect light anisicoria

Question 6

Horners testing with apraclondine:

Answer 6

Apraclondine (0.5-1%), 1 dose. A-adrenergic agoinist, denervation hypersensitivity. 40mins Horners will have abnormal lid raise, pupil dilate, normal eye remain unchanged.

Question 7

Horners syndrome testing/signs:

Answer 7

Unilateral miosis, ptosis, anhidrosis. Congenital iris heterochromia (lack of sympathetic for melanocyte development)
Dilation lag of mitotic pupil in dark (5-10s dark)
Anisocoria greater at 5s and lesser at 15s
No abnormal light/near constriction

Question 8

Horners lesion localization

Answer 8

1% hydroxyamphetamine, ^norepinephrine release at neuromuscular junction for bilateral dilation.
First/second order neuron > dilation
>48h following cocaine/apraclondine, hard to obtain

Question 9

Horners causes by lesion location:

Answer 9

First order: hypothalmic/brainstem/spinal cord lesion
Second order: lung/sympathetic tumor, thyroid lesion
Third order: carotid artery damage, cavernous sinus lesion

Question 10

Anisocoria testing when greater in dark:

Answer 10

Small pupil anisocoria.
Apraclonidine / cocaine:
No (clondine)/greater (cocaine) dilation > physiologic
Potic dilation(clondine)/non-dilation (cocaine) > horners > hyrodyamphetaime/MRI

Question 11

Anisicoria testing when greater in light

Answer 11

Large pupil anisocoria
Motility/ptosis abmornal > CN3 palsy > MRI/CTA
Full motility/no ptosis + worm constriction > tonic pupil
Full motility/no ptosis > dilute pilocarpine > tonic on constriction
Dilute pilo. Non-constriction > non-dilute > constriction in third nerve palsy / pharmacologic on mydryasis

Question 12

Symptoms of horners syndrome:

Answer 12

Ipsilateral anhidrosis of face
Miosis in dark
2mm partial ptosis (muller denervation)
Partial lower lid raise

Question 13

Advantages of apraclondine over cocaine in pharmacologic testing of horners:

Answer 13

Available commercially
Longer shelf life
No stigma
Does not require normal second pupil
May have false negatives in recent horners