UCLA

PURPOSE:To evaluate a technique for simultaneous quantitative T2 and apparent diffusion coefficient (ADC) mapping in the heart (T2 +ADC) using spin echo (SE) diffusion-weighted imaging (DWI). THEORY AND METHODS:T2 maps from T2 +ADC were compared with single-echo SE in phantoms and with T2 -prepared (T2 -prep) balanced steady-state free precession (bSSFP) in healthy volunteers. ADC maps from T2 +ADC were compared with conventional DWI in phantoms and in vivo. T2 +ADC was also demonstrated in a patient with acute myocardial infarction (MI). RESULTS:Phantom T2 values from T2 +ADC were closer to a single-echo SE reference than T2 -prep bSSFP (-2.3 ± 6.0% vs 22.2 ± 16.3%; P < 0.01), and ADC values were in excellent agreement with DWI (0.28 ± 0.4%). In volunteers, myocardial T2 values from T2 +ADC were significantly shorter than T2 -prep bSSFP (35.8 ± 3.1 vs 46.8 ± 3.8 ms; P < 0.01); myocardial ADC was not significantly (N.S.) different between T2 +ADC and conventional motion-compensated DWI (1.39 ± 0.18 vs 1.38 ± 0.18 mm2 /ms; P = N.S.). In the patient, T2 and ADC were both significantly elevated in the infarct compared with remote myocardium (T2 : 40.4 ± 7.6 vs 56.8 ± 22.0; P < 0.01; ADC: 1.47 ± 0.59 vs 1.65 ± 0.65 mm2 /ms; P < 0.01). CONCLUSION:T2 +ADC generated coregistered, free-breathing T2 and ADC maps in healthy volunteers and a patient with acute MI with no cost in accuracy, precision, or scan time compared with DWI. Magn Reson Med 79:654-662, 2018. © 2017 International Society for Magnetic Resonance in Medicine.