Horner's syndrome

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Horner's syndrome

The association, on one side, of a drooping upper eyelid, an apparently slightly sunken eyeball, a pupil reduced in size compared with the other, and absence of sweating on the same side of the face. This syndrome is an indication that certain nerves in the neck have been damaged, possibly by cancer. (Johann Friedrich Horner, 1831–1886, Swiss ophthalmologist)
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005