LANGERHANS CELL HISTIOCYTOSIS OF BONE - MR-IMAGING

Magnetic resonance (MR) images of 12 pathologically proven lesions of Langerhans cell histiocytosis (LCH) of bone were reviewed retrospectiv ely. MR identified all lesions, three of which were not identified on plain radiographs. In all cases, MR showed greater abnormality than di d plain radiographs. With one exception, all lesions were hypointense on T1-weighted images and hyperintense on T2-weighted images. The lesi ons and associated soft tissue abnormalities were very conspicuous on short TI inversion sequences and T1-weighted post-contrast images. Fol low-up MR studies in two patients after chemotherapy showed decreased size and enhancement of lesions compared with baseline studies.