Objective: To use modern computed tomography (CT) imaging to quantify the incidence of asymptomatic incidental orbital calcifications and describe their histological features.
Materials and methods: One hundred orbital CT scans were reviewed. In addition, patients who had orbital calcification(s) detected on a brain CT scan were examined by the ophthalmology service.
Results: Of the orbital CT scans, 2% had bilateral drusen of the optic nerve head, 3% had calcified scleral plaques anterior to the medial or lateral rectus muscles, and 3% had bilateral ossification of the trochlear apparatus. Routine brain CT scans detected asymptomatic calcifications of the sclera and dura surrounding the proximal optic nerves.
Conclusion: Incidental asymptomatic orbital calcifications are commonly encountered on modern high-resolution CT images of the brain and orbit. This article should help the clinician to confidently distinguish these densities from foreign bodies or pathological calcifications.