Magnetic resonance imaging of clival marrow in patients with anorexia nervosa.

Abstract

Hematological abnormalities, commonly associated with anorexia nervosa (AN) patients, are thought to be the results of serous atrophy in the bone marrow. Magnetic resonance imaging (MRI) has been utilized to ascertain T1 and T2 prolongation of marrow intensity in the lumbar spine, pelvis and proximal femora. The results correlate well with the severity of hematological abnormalities, and body mass index. More importantly, the propensity for peripheral marrow involvement of T2 prolongation contrasts with the axial involvement in other marrow disorders. MRI undertaken in patients with AN to exclude hypothalamic tumor showed that the clival marrow was equivalent to the peripheral marrow. The signal pattern of clival marrow on sagittal T1 weighted MR images was evaluated in four teenage female patients with AN complicated by hematological abnormalities. Although the clival marrow intensity should be uniformly high in teenagers, three patients, two with pancytopenia and one with leukopenia and anemia, exhibited homogeneous low intensity. One patient who had leukopenia only and the highest body mass index, showed inhomogeneous low intensity. The signal changes returned to normal in all patients but one, who died before examination after 6-11 months, at which time the others had almost recovered their original weight and normal hemogram. T1 prolongation in the clival marrow represents bone marrow dysfunction and the inhomogeneity of the signal change may imply relative preservation of hematopoiesis and body fat composition. Lack of knowledge of this phenomenon may lead to diagnostic confusion with other marrow disorders on cranial MRI.