Correlation of T1 and T2 relaxation rates in normal bone-marrow water with serum ferritin concentration

Purpose: This study was made to clarify the paramagnetic effect of iron stored in the hematopoietic tissue of bone marrow. Material and methods: The T1 and T2 relaxation times of bone-marrow water in the L1-3 vertebrae of 20 healthy individuals were measured by MR imaging with a 1.5 T magnet. The chemical shift misregistration effect was used to isolate the bone-marrow water. The results were compared with the serum ferritin concentration. Results and Conclusion: Although no correlation between the T1 relaxation rate of the water fraction and the serum ferritin concentration was evident, the T2 relaxation rate of the water fraction showed strong linear correlation with the serum ferritin concentration (r=0.87, p<0.001). Thus, T2 of bone-marrow water accurately reflects the amount of iron in normal bone marrow. This finding may be useful in the evaluation of the characteristics of hematopoietic tissue in bone marrow. (orig.)