Simultaneous measurement of T and apparent diffusion coefficient (T +ADC) in the heart with motion-compensated spin echo diffusion-weighted imaging.

PURPOSE

To evaluate a technique for simultaneous quantitative T and apparent diffusion coefficient (ADC) mapping in the heart (T +ADC) using spin echo (SE) diffusion-weighted imaging (DWI).

THEORY AND METHODS

T maps from T +ADC were compared with single-echo SE in phantoms and with T -prepared (T -prep) balanced steady-state free precession (bSSFP) in healthy volunteers. ADC maps from T +ADC were compared with conventional DWI in phantoms and in vivo. T +ADC was also demonstrated in a patient with acute myocardial infarction (MI).

RESULTS

Phantom T values from T +ADC were closer to a single-echo SE reference than T -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 T values from T +ADC were significantly shorter than T -prep bSSFP (35.8 ± 3.1 vs 46.8 ± 3.8 ms; P < 0.01); myocardial ADC was not significantly (N.S.) different between T +ADC and conventional motion-compensated DWI (1.39 ± 0.18 vs 1.38 ± 0.18 mm /ms; P = N.S.). In the patient, T and ADC were both significantly elevated in the infarct compared with remote myocardium (T : 40.4 ± 7.6 vs 56.8 ± 22.0; P < 0.01; ADC: 1.47 ± 0.59 vs 1.65 ± 0.65 mm /ms; P < 0.01).

CONCLUSION

T +ADC generated coregistered, free-breathing T 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.