Evaluation of the relationship between splenic iron overload and liver, heart and muscle features evident on T2*-weighted magnetic resonance imaging.

Abstract

Splenic iron overload is the most common clinical condition in patients with thalassemia. However, few studies of the effects of splenectomy have been published. To evaluate the relationship between splenic iron overload and liver, heart and muscle features visible in T2*-weighted magnetic resonance imaging, and to investigate the effects of splenectomy on these tissues in patients with beta-thalassemia major (TM). We retrospectively included 131 patients (76 male and 55 female) diagnosed with TM. All radiological assessments were performed with the aid of a Philips Achieva 1.5T scanner running a multiecho gradient-echo sequence. Hepatic and splenic T2* values were assessed in the same gradient multiecho series. Muscle T2* values were assessed in the shoulder girdle muscles adjacent to the heart area. The relationships among splenic T2*, hepatic T2*, cardiac T2* and muscle T2* parameters, serum ferritin levels, age and other parameters were evaluated. The splenic T2* value correlated with serum ferritin level and the hepatic T2* value (p < 0.001 and p < 0.001, respectively). The splenic T2* value did not correlate with age, cardiac or muscle T2* values, or with spleen size (p = 0.27, 0.21, 0.99, and 0.39, respectively). The muscle T2* value correlated weakly with the serum ferritin level (p = 0.022). The cardiac T2* value was lower and the liver size greater in patients who had undergone splenectomy compared with those who had not (p < 0.001 and 0.001, respectively). Splenic iron overload correlated with hepatic overload and the serum ferritin level. Splenectomy increased cardiac iron overload and triggered liver enlargement. However, the muscle iron overload was low and the muscles were therefore unaffected by splenectomy.