Trochlear calcification mimicking an orbital foreign body.

A 39-year-old man presented with diplopia 1 day following left orbit trauma. CT scan and ultrasound showed a left trochlear hyperintensity that was interpreted by both the radiologist and echographer as a metallic foreign body. Surgical exploration failed to identify a foreign body. The patient presumably had preexisting trochlear calcification with a post-traumatic nonconcomitant small-angle vertical deviation and diplopia. Calcification should be considered in the differential diagnosis of trochlear hyperintensity noted on imaging studies.