Patient, male, 59 years old. Date of first visit： September 14, 2010. Main complaint： double vision accompanied by dropping of eyelid of left side, horizontal strabismus of left eye ball for one month. Medical history： sudden onset of double vision on August 10, 2010 due to fatigue after long distance driving, there are dropping of eyelid of left side, horizontal strabismus of left eye ball, turning to the right slowly, and these symptoms become aggravated progressively.
