oculomotor

A 50-year-old female with no past medical history presents to the ED with a diffuse, constant headache onset a few weeks. The patient describes droopiness of the left eye and double vision associated with specific directional movements of the eye. On exam, you note ptosis of the left eye with findings as indicated in the photograph below (inability to adduct, ability to abduct). The left pupil is dilated at 5mm and minimally reactive to light; the right pupil is 3mm and reactive. The remaining cranial nerve testing and components of the neurological exam are normal.