The reproducibility of cardiac and liver T2* measurement in thalassemia major using two different software packages.

Abstract

In b-thalassemia major (TM) multiple blood transfusions are needed for survival. As a consequence these patients present iron overload in different organs, including heart and liver. Magnetic resonance imaging using a bright blood gradient echo sequence has been successfully used for the quantification of tissue iron. The aim is to evaluate of the accuracy and precision in the evaluation of liver and myocardial T2* values in TM using two different analytical software solutions. Thirty TM patients aged 20-56years (mean age 37, 11M/19F) were scanned in a GE 1.5 T CVI system. Each scan included the measurement of heart and liver T2* and the left ventricular ejection fraction using standard techniques. The analysis of T2* of heart and liver was done using the two different analytical software solutions: the "Functool" protocol by GE and the T2* module of QMassMR v7.4 by Medis medical imaging systems bv, Leiden, The Netherlands. The cardiac and liver T2* measurements showed that both software solutions allow reproducible measurements with low intra-observer variations (accuracy<0.3ms, precision<2ms). There is a small but significant difference between the two solutions of 2.4ms in cardiac and of 1.5ms in liver measurements. However, from the clinical point of view these differences (<2ms) are small with negligible impact on the patient's treatment management. The comparison of the T2* measurements using the two analytical software solutions proved that both techniques enable reproducible measurements for the evaluation of iron overload in heart and liver.