59-year-old man comes to the emergency department with diplopi | Uworld | Step 1

59-year-old man comes to the emergency department with diplopia that started several hours ago. His past medical history is significant for long-standing diabetes with poor glycemic control, right-knee osteoarthritis, and peptic ulcer disease. Physical examination shows right-sided ptosis with the right pupil in the inferolateral position. Pupils are equal in size and reactive to light bilaterally.