Magnetic resonance imaging reveals a markedly inhomogeneous distribution of marrow cellularity in a patient with myelodysplasia.

A 47-year-old male patient with myelodysplasia showed increasing values of serum lactate dehydrogenase (up to 3500 units/l) and an increasing blast count. Several biopsies (taken from the posterior iliac crest) revealed marked hypocellularity. In contrast, magnetic resonance imaging of the marrow demonstrated an inhomogeneous distribution of marrow with hypocellular and also large hypercellular areas not detected by cytological and histological analysis. A location for biopsy of hypercellular marrow was provided by T1-weighted and water-selective magnetic resonance imaging. The findings in the patient were compared with those in a matched healthy volunteer.