Non-invasive myocardial iron assessment in thalassaemic patients: T2 relaxometry and magnetization transfer ratio measurements

Abstract
Purpose: To compare T2 relaxometry and magnetization transfer ratio (MTR) measurements of myocardial tissue in normal volunteers and thalassaemic patients for assessment of the myocardial iron levels. Material and Methods: All examinations were done on a 1 T MR system using a multi-echo spin-echo sequence with 8 echoes for T2 measurements and a gradient echo sequence for MTR measurements. Diastolic cardiac triggering was used in both sequences. Ten patients and 10 normal subjects were included in the study. T2 and MTR measurements were correlated with serum ferritin levels. Results: Regression analysis between T2 and MTR measurements and ferritin demonstrated a reversed linear relationship, (r=−0.932, p<0.05) and (r=−0.824, p<0.05), respectively. Mean T2 relaxation time and mean MTR of the normal subjects (57.95±4.9 ms and 43.70±3.3%) was significantly higher than that of the thalassaemic patients (38.8±6.2 ms and 26.40±6.1%) ( p<0.01), respectively. Conclusion: MTR measurements can be used to complement T2 measurements for non-invasive myocardial iron assessment.