Background. MRI has emerged for the noninvasive assessment of iron overload in various tissues. The aim of this paper is to evaluate hepatic and pancreatic iron overload by weighted gradient echo MRI in young beta-thalassemia major patients and to correlate it with glucose disturbance and postsplenectomy status. Subjects and Methods. 50 thalassemic patients, in addition to 15 healthy controls. All patients underwent clinical assessment and laboratory investigations. Out of 50 thalassemic patients, 37 patients were splenectomized. MRI was performed for all subjects. Results. All patients showed significant reduction in the signal intensity of the liver and the pancreas on GRD compared to controls, thalassemic patients who had abnormal glucose tolerance; diabetic and impaired glucose tolerance patients displayed a higher degree of pancreatic and hepatic siderosis and more drop in their signal intensity than those with normal blood sugar level. Splenectomized thalassemic patients had significantly lower signal intensity of the liver and pancreas compared to nonsplenectomized patients. Conclusion. gradient echo MRI is noninvasive highly sensitive method in assessing hepatic and pancreatic iron overload in thalassemic patients, more evident in patients with abnormal glucose tolerance, and is accelerated in thalassemic splenectomized patients. 1. Introduction β-Thalassemia major is a hereditary hemolytic anemia that is treated with multiple blood transfusions. A major complication of this treatment is iron overload, which leads to cell death and organ dysfunction [1]. Iron accumulates initially in the reticuloendothelial system (bone marrow, spleen, and liver) and then in the hepatocytes, the heart (myocytes), and the endocrine glands [2]. The turnover of iron in the hepatocytes, myocytes, and endocrine glands is very low. Chelation therapy has been used to eliminate it [3], methods to estimate total body iron stores are required, and serum ferritin acts as a reliable marker but can yield false results in the presence of inflammation and liver disease [4]. Liver is the primary site for iron storage in patients with hemochromatosis or transfusion-dependent anemia; therefore, liver iron concentration (LIC) accurately reflects total body iron stores [5]. Classically, liver iron assessment has been performed by needle biopsy. This procedure carries a 0.5% complication risk and it is also disliked by patients [6]. Clinical management of these patients is also based on the assessment of liver iron stores for several reasons. First, liver iron was shown to correlate
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