Assessment of Organ Specific Iron Overload in Transfusiondependent Thalassemia by Magnetic Resonance Imaging Techniques

The consequence of repeated blood transfusions in thalassemia is iron overload in different organs. Magnetic resonance imaging (MRI) is a reliable, noninvasive and accurate method for iron detection in various tissues, hence the introduction of MRI has revolutionized the management of these patients and improved the life expectancy of them. Cardiac MRI T2* has a profound effect not only on estimation of severity of cardiac siderosis, but on intensification of chelation regimens and survival of patients. Liver hemosiderosis is also a common morbidity among thalassemia patients, since the liver represents the dominant iron storage organ in the body; however, the relationship between total body iron and liver iron concentration (LIC) is challenging. Pancreatic iron overload occurs in 75-100% of patients with thalassemia major, but the association between pancreatic R2* and development of diabetes mellitus has not been established in the studies. On the other hand, there is a strong correlation between pancreatic R2* and cardiac R2*, so pancreatic R2* could predict left ventricular function. The most prevalent endocrinopathy in patients with thalassemia is hypogonadotropic hypogonadism which has been correlated with pituitary iron overload. Published data about kidney and adrenal MRI is limited, and further studies are needed to determine their clinical significance.