All of the following are clinical findings of Horner syndrome, EXCEPT:

The physical findings of ipsilateral ptosis and miosis and anhidrosis are characteristic of Horner syndrome. Interruption of the sympathetic nerve impulses controlling the Mueller muscle in the upper eyelid and the iris dilators causes these classic findings. Retraction of the eyeball (enophthalmos), considered a component of the syndrome, is probably an illusion created by narrowing of the palpebral fissure. Ref: Ropper A.H., Samuels M.A. (2009). Chapter 14. Disorders of Ocular Movement and Pupillary Function. In A.H. Ropper, M.A. Samuels (Eds), Adams and Victor's Principles of Neurology, 9e.