A 54-year-old man presented with a 3-day history of right ptosis and double vision. He was otherwise healthy and did not take any regular medications. Initially, he had horizontal diplopia on the first day that was worse at the end of the day, but this resolved when the right eyelid ptosis became complete. He denied any difficulty with his speech, swallowing, weakness, or sensory changes.

He presented to the emergency department, and the emergency department physician reported a normal neurological examination result apart from the right-sided ptosis and limited eye movements. He was referred to ophthalmology and had a visual acuity of 20/20 OU. Both pupils were equal sizes and reactive to light. He was found to only have a complete limitation of elevation of his right eye and a limitation of abduction in his left eye (Figure). He was orthophoric in primary position, and there were no eyelid twitches. Orbicularis oculi strength was reduced on both sides. A dilated fundus examination had normal results bilaterally. An initial neurological examination, including assessments of motor strength in the upper and lower extremities and reflexes and a sensory examination, had normal results.

一名 54 岁男性因右侧上睑下垂和复视 3 天就诊。他在其他方面很健康，没有服用任何常规药物。最初，他在第一天有水平复视，一天结束时更严重，但是当右眼睑下垂完全消失时，这种情况就消失了。他否认言语、吞咽、虚弱或感觉变化有任何困难。

他到急诊科就诊，急诊科医师报告除了右侧上睑下垂和眼球运动受限外，其他神经系统检查结果正常。他被转诊至眼科，视力为 20/20 OU。两个瞳孔大小相等，对光有反应。他被发现只有右眼完全抬高受限和左眼外展受限（图）。他在主要位置是正直的，并且没有眼睑抽搐。两侧的眼轮匝肌强度降低。双侧扩张的眼底检查结果正常。最初的神经系统检查，包括对上下肢运动强度和反射的评估以及感觉检查，结果正常。