Imaging findings of atypical mycobacterial infection in the temporal bone

Atypical mycobacterial (AM) infection of the temporal bone is rare, and its early diagnosis is critical for a good patient outcome. The imaging findings of AM infection have been only briefly reported. We present the computed tomographic and magnetic resonance findings of AM involvement of the entire temporal bone in an immunocompromised patient, and we discuss the differential diagnosis. The scattered areas of both bone sclerosis and erosion may help the radiologist suggest the diagnosis of an indolent process such as tuberculosis or AM and allow initiation of early treatment.