Tissue iron concentrations in patients suspected of iron overload are currently estimated using the concentration of ferritin in serum. Because serum ferritin is an acute-phase reactant, we hypothesized that it is not a reliable predictor of amount of tissue iron. MRI relaxation times decrease as the concentration of iron in tissues increases. The MRI T2* and T2 relaxation times evaluated from liver and myocardial interventricular septum will be measured in approximately 30 iron patients with primary or secondary hemochromatosis. MRI measurements from the interventricular septum will be correlated with MRI results from the liver, serum ferritin, serum iron (SI), total iron binding capacity (TIBC), and percent iron binding (SI/TIBC × 100). To date we have enrolled seven patients and shown that it is feasible to study both myocardial and liver iron in one MRI session. Our preliminary findings suggest that serum ferritin may not be an accurate predictor of amount of iron in liver and heart as measured by MRI. We conclude that (1) MRI measurements to determine amount of myocardial and liver iron can be obtained in one session and (2) our preliminary findings suggest that serum ferritin may not be an accurate predictor of amount of iron in liver and heart as measured by MRI, but these initial data will be verified via study of additional iron overload patients.