Diagnostic imaging plays a major role in the management of patients with Langerhans cell histiocytosis. Plain radiography depicts most lesions. Nuclear scintigraphy may detect additional areas of bone involvement, but its routine use is controversial. Ultrasonography may be used to evaluate the abdomen for evidence of solid organ involvement. CT and MR imaging are often of great value in clarifying and delineating findings seen on plain radiographs and other imaging modalities. Ultimately, the choice of imaging study depends on the patient's clinical presentation and the body part affected.