Horner's syndrome is caused by paralysis of the cervical sympathetic nerve, resulting in ptosis, miosis, enophthalmos, anhydrosis, and loss of the ciliospinal reflex on the affected side. It can be classified as congenital or acquired. Peripheral Horner's syndrome occurs distal to the superior cervical ganglion, while central Horner's syndrome occurs proximal to the ganglion. Causes include lesions of the first order neuron in the hypothalamo-spinal pathway, preganglionic lesions of the second order neuron, or postganglionic lesions at the level of the internal carotid artery.

1. HORNER’S SYNDROME / OCCULOSYMPATHETIC PALSY Dr. KARTHIK TUMMALA 3rd
year PG
HISTORY :
• Johann Friedrich Horner, the Swiss ophthalmologist discovered this syndrome in 1869.
• Occurs due to paralysis of cervical sympathetic nerve.
SIGNS:
• Ptosis (affected side)-due to weakness of Muller’s muscle
• Miosis (constricted pupil)-due to weakness of dilator pupilae
• Enophthalmos (impression that eye is sunk)
• Anhydrosis (decreased sweating)
• Ciliospinal reflex (Dilatation of the normal pupil when the skin of the neck is pinched) lost
• Upside down ptosis (slight elevation of lower lid)
• Dilation lag (slow response of pupil to light)
• Blood shot conjunctiva & Flushing of face on affected side
• In a semi-darkened room, affected pupil dilates very poorly, the normal contra lateral pupil dilates much better.
• Cocaine eye drops fails to dilate the Horner’s pupil whereas it dilates the normal pupil.
• CLASSIFICATION: 1. Congenital : light colored iris and ipsilateral facial hemi atrophy.
2. Acquired : ocular hypotonia.
Features Peripheral Horner’s Central Horner’s
Site Distal to superior cervical ganglion
(post ganglionic)
Proximal to superior cervical ganglion
(preganglionic)
Sweating Not Affected Affected over same side head, neck, arm, upper
trunk.
1% Hydroxy Amphetamine
test
No effect Dilatation
Adrenaline1:1000 Dilatation and Lid Elevation No effect
Ciliospinal reflex Absent Present
• CAUSES:
FIRST ORDER NEURON LESIONS :
Central lesions that involve the
hypothalamo spinal pathway
SECOND ORDER NEURON LESIONS :
Preganglionic lesions
THIRD ORDER NEURON LESIONS :
Postganglionic lesions at the level of internal carotid artery
1.Arnold-Chiari malformation 1.Pancoast tumour 1.Internal carotid Artery dissection
2.Basal meningitis 2..Aneurysm/Dissection of Aorta/
Subclavian /Common carotid Artery
2. Carotico cavernous fistula
3.Lateral medullary syndrome 3.Cervical rib 3.Cluster/ migraine headache
4.Demyelinating disease 4.Chest tubes 4.Raeder syndrome
(Oculosympathetic paresis and ipsilateral facial pain with
variable involvement of the Trigeminal and Oculomotor.N)
5.Intrapontine hemorrhage
6. neck trauma
7. syringomyelia
5. Lymphadenopathy (Hodgkin/TB/
leukemia /Mediastinal tumour)