Computed tomography imaging of the leg in Erdheim-Chester disease

Computed tomography imaging of the left leg in a 48-year-old male with Erdheim-Chester disease shows an expansile lytic lesion in the distal tibia with lobulated endosteal scalloping, and multiple foci of calcified matrix. There is mild subcutaneous soft tissue stranding anteriorly and medially. Within the fibula, the marrow also appears abnormal, but there is no endosteal scalloping.