Horner syndrome: tribute to Professor Horner on his 190th birthday.

This paper reviews some aspects of the life and work of Professor Johann Friedrich Horner, on the occasion of the 190th anniversary of his birthday and 152 years after the publication of "Über eine Form von Ptosis". It also shows the importance of the historical description of ptosis, myosis and anhidrosis associating those symptoms with sympathetic cervical damage. He pharmacologically confirmed the impairment of sympathetic innervation to the eye and preserved parasympathetic function.