Lipoblastomatosis of the shoulder: unusual MR appearance.

Lipoblastomatosis is a rare benign lipomatous tumour of childhood and infancy, classically showing high signal identical to fat on T1 weighted images. A case of histologically proven lipoblastomatosis in an infant is presented, in which MRI showed low signal on T1 weighted images identical to that of muscle instead of high signal. This appearance has not been previously reported.