Wk11 Horner Syndrome

Question 1

What is Horner’s syndrome?

Answer 1

• Caused by an interruption of sympathetic innervation supplying eyes and face
• Can be congenital, hereditary, or acquired
• Can be categorised into 3 categories
  o Lesion to 1st order neurons (central)
  ▪ Base of brain to upper part of spinal cord
  ▪ Result: anhidrosis of face, trunk and arms
  o Lesion to 2nd order neurones (preganglionic)
  ▪ Spinalcolumntoneck
  ▪ OnlyAnhidrosisofface
  o Lesion to 3rd order neurons (Postganglionic)
  ▪ Fromnecktofacialskin,muscleofeyelidandiris
  ▪ Noanhidrosisifoccursatapointafternervehasbranchedofftosweatgland
• Both 2nd and 1st order cause ptosis, anhidrosis and miosis
• “Other symptoms” occur irrespective to neurone damage

Question 2

Symptoms

Answer 2

Common symptoms are unilateral

• Anhidrosis – inactivation of sweat glands → no sweating
• Ptosis – inactivation of superior tarsal muscle → droopy eyelid
• Miosis – inactivation of dilation papillae → excessive constriction of pupil

Other symptoms

• Neck pain
• Muscle weakness/lack of muscle control
• Enophthalmos - Sunken appearance
• Dizziness/Severe headache

Question 3

How to diagnose?

Answer 3

• Eye drop test
  o Determine location of nerve damage by how pupil respond to eye drops
• chest x-ray and brain scan
  o Check entire sympathetic pathway issue in e.g., cervical ganglia of sympathetic chain

Question 4

Likelihood + extent of recovery

Answer 4

• Recovery can take from 3 weeks to 1year

- Horner’s syndrome disappears if underlying medical condition is treated e.g., tumour removed in surgery

Question 5

Innervation of eye

Answer 5

• innervated by both Parasympathetic Nervous System (PNS) and Sympathetic Nervous System (SNS)

SNS
o Preganglionic fibres from t1 and t2 form synapses in superior cervical ganglion
o Postganglionic sympathetic fibres leave ganglion → pass through ciliary ganglion → then
innervate
▪ Dilation pupillae muscle – contraction→pupil dilation “see lighter” (alpha1 receptor)
▪ Ciliary muscle – relaxation→see far distances (Beta 2 receptor)
▪ Superiortarsalmuscle–eyelidelevation,sweatglandinnervation

PNS
o Postganglionic parasympathetic fibres innervate (think contraction)
▪ Sphincterpupillaemuscle–pupilconstriction“lesslight”(M3receptor)
▪ Ciliarymuscle–“seecloseup”(M3receptor)