Horner's Syndrome: Loss of sympathetic nervous system input to (in this case)left eye. Note that left pupil is smaller than right. Also that left eyelid covers a greater portion of eye than on right (known as ptosis). The etiology in this case was idiopathic, though it can be associated with tumors occurring at the apex of the lung, among other things. Charlie Goldberg, M.D. - UCSD Catalog of Clinical Images #Clinical #Ophthalmology #Photo #Horners #Syndrome #Ptosis #UCSDH