Radiographic findings of internal organ systems commonly affected by ECD. (A) Axial CT scan of abdomen of an ECD patient demonstrating dense infiltration of perinephric fat commonly seen in ECD and referred to as a “hairy kidney” appearance (red arrow). Circumferential soft-tissue sheathing of the thoracic aorta seen in a subset of ECD patients and referred to as a “coated aorta” (blue arrow). Right atrial mass is demonstrated in B. (C) Lung parenchymal infiltration on chest CT in an ECD patient. Axial postgadolinium T1 MRI in (D) demonstrates expansile enhancement of the pachymeninges (thick arrow) as well as orbital masses (thin arrow) and (E) enhancing lesions in the dentate nuclei of the cerebellum. (F) Sagittal postgadolinium T1 MRI shows thickening and enhancement of the pituitary stalk.