Horner's syndrome

- unilateral pupillary constriction with slight ptosis and enophthalmos indicates a sympathetic pathway lesion on ipsilateral side
- diminution of sweating on the same side depends upon the level of lesion
  i) central lesion : entire half of head, arm and upper trunk
  ii) neck lesion proximal to superior cervical ganglion (preganglionic): diminished facial sweating
  iii) lesion distal to superior cervical ganglion (postganglionic) : do not affect sweating at all
- Iris heterochromia if congenital or long standing
- Tests
   i) 4% cocaine drop (Horner does not dilate)
  ii) 1% hydroxyamphetamine (post ganglionic Horner does not dilate)