<prompt> All of the following are features of Horners syndrome EXCEPT:PtosisMiosisHeterochromia iridisExophthalmos  <response>: Ans. d ExophthalmosRef: Grays 41sted.469 Horner syndrome presents with: Ptosis Miosis Anhydrosis and,TRIAD Apparent enopnthalmos and not exophthalmos;. This enophthalmus is due to paralysis of the orbitalis muscle of the orbit, which normally keeps the eyeball prominent. Its nerve supply is sympathetic -T1 and when paralyzed leads to appearance of sunken eyeball. Most cases are idiopathic, but it could be due to brainstem lesions, carotid dissection, or neoplasm compressing upon the sympathetic chain E.g., Pancoast tumour. Symptoms of horners syndrome are secondary to sympathetic nerve Tl lesion. Sympathetic nervous system is concerned with the frightfightflight Emergency reaction and leads to: Elevation of upper eyelid by Muller muscle wide open eyes Pupillary dilatation by Dilator pupillae wide open pupils Sweating sudomotor Pallor of the skin vasomotor This activity is under Sympathetic T-l nerves in the face, and are lesioned in Horner syndrome leading to: Drooping of upper eyelid ptosis - due to unopposed orbicularis oculi Pupillary constriction miosis - due to unopposed sphincter papillae Loss of sweating anhydrosis Red flushed face - due to loss of vasoconstrictive tone to the skin. 