Imaging features of type-B Niemann-Pick disease

We report two cases of a mild form of type-B Niemann-Pick disease manifesting as an adult-onset chronic non-neuropathic clinical picture. Femoral T1- and T2-weighted low-intensity non-enhancing coarse bone marrow pattern was evident on femoral MR associated with splenic hypodense nodule(s) on abdominal CT. The role of imaging is discussed in relation to current techniques of confirmation of this entity based on demonstration of lipid-laden cells within marrow aspirates (which are often sea-blue histiocytes) and sphingomyelinase assay of cultured skin fibroblasts.