Giant Cell Tumor of the Temporal Bone

A 47-year-old woman with progressive headache, dizziness, and tinnitus was referred to an outpatient imaging center for MR imaging evaluation of the brain and internal auditory canals. Findings on MR imaging initially prompted a differential diagnosis that favored meningioma or schwannoma, based on the presence of a lesion that involved the internal auditory canals. However, careful review of the MR imaging features, and correlation with CT, led to a diagnosis of a primary osseous lesion.