In vivo comparison of myocardial T1 with T2 and T2* in thalassaemia major.

PURPOSE

To compare myocardial T1 against T2 and T2* in patients with thalassemia major (TM) for myocardial iron characterization.

MATERIALS AND METHODS

A total of 106 TM patients (29 ± 10 years; 58 males) were studied on a 1.5 Tesla scanner using dedicated T1, T2*, and T2 relaxometry sequences. A single mid-ventricular short axis slice was acquired within a breath-hold.

RESULTS

In patients with myocardial iron overload (T2* < 20 ms; n = 52), there were linear correlations between T2 and T2* (r = 0.82; P = 0.0), and between T1 and T2* (r = 0.83; P = 0.0). In patients with no myocardial iron (n = 54), T2* values were scattered with no significant correlation against T2 or T1. For all patients (n = 106) there was a strong linear correlation (r = 0.93; P = 0.0) between myocardial T1 and T2.

CONCLUSION

In patients with iron overload, myocardial T2 and T1 are correlated with T2*. In patients with low or normal myocardial iron concentration, other factors become dominant in affecting T2* values as shown by scattered T2* data. Myocardial T1 correlates linearly with T2 measurements in all patients suggesting that these two relaxation parameters avoid extrinsic magnetic field inhomogeneity effects and may potentially provide improved myocardial tissue characterization.