(1) Department of Clinical Radiology, University of Munich, Marchioninistrasse 15, 81377 Munich, Germany
Abstract:
Diffusion-weighted imaging allows for measurement of tissue microstructure and reflects the random motion of water protons.
It provides a new method to study bone marrow and bone marrow alterations on the basis of altered water-proton mobility in
various diseases. Different diffusion-weighted methods have proved to be capable of differentiating between benign edema and
tumorous involvement of bone marrow. It is especially useful for the distinction of acute benign osteoporotic and malignant
vertebral compression fractures. Diagnosis is based on the contrast to normal bone marrow. Hypo- or isointensity reflects
acute benign collapse, whereas hyperintensity is indicative of the tumorous nature of a fracture. Apparent diffusion coefficients
(ADC) are significantly lower in metastatic disease than in bone marrow edema. Furthermore, bone marrow cellularity can be
estimated by ADC measurements. Diffusion-weighted imaging might be helpful for monitoring response to therapy in metastatic
disease.