Assessment of iron overload with T2* magnetic resonance imaging.

T2* is a magnetic relaxation property of any tissue and is inversely related to intracellular iron stores. Measurement is simple, quick, and robust and has high reproducibility. The ability to measure ventricular function plus T2* in the heart and liver during the same scan has revolutionized the understanding of iron storage disease and the management of the iron-loaded patient. The early findings using T2* challenged conventional teachings, and both the technique and the findings were initially viewed with scepticism. However, after a decade of work in validating, calibrating, and expanding access to this method, it is now accepted as the method of choice for tissue iron assessment. In the UK, where T2* measurement was first used in the clinical care of patients with thalassemia major, a large and significant fall in mortality has been seen in this patient group.