A man with proptosis of the left eye

A 50-year–old man without systemic disease presented to the emergency department with progressive proptosis of the left eye (Figure 1) after a motor vehicle accident 4 weeks ago. On ophthalmic examination, his visual acuity was 20/40 in the left eye and 20/20 in the right eye. The ocular motility test revealed limited medial gaze of the left eye. Point-of-care ultrasound demonstrated an engorged vessel with a pulsatile flow directed toward the probe at the medial side of the left orbital cavity (Figure 2 and Video 1).