Measurement of Myocardial T1? with a Motion Corrected, Parametric Mapping Sequence in Humans.

ABSTRACT:

Purpose

To develop a robust T1? magnetic resonance imaging (MRI) sequence for assessment of myocardial disease in humans.

Materials and methods

We developed a breath-held T1? mapping method using a single-shot, T1?-prepared balanced steady-state free-precession (bSSFP) sequence. The magnetization trajectory was simulated to identify sources of T1? error. To limit motion artifacts, an optical flow-based image registration method was used to align T1? images. The reproducibility and accuracy of these methods was assessed in phantoms and 10 healthy subjects. Results are shown in 1 patient with pre-ventricular contractions (PVCs), 1 patient with chronic myocardial infarction (MI) and 2 patients with hypertrophic cardiomyopathy (HCM).

Results

In phantoms, the mean bias was 1.0 ± 2.7 msec (100 msec phantom) and 0.9 ± 0.9 msec (60 msec phantom) at 60 bpm and 2.2 ± 3.2 msec (100 msec) and 1.4 ± 0.9 msec (60 msec) at 80 bpm. The coefficient of variation (COV) was 2.2 (100 msec) and 1.3 (60 msec) at 60 bpm and 2.6 (100 msec) and 1.4 (60 msec) at 80 bpm. Motion correction improved the alignment of T1? images in subjects, as determined by the increase in Dice Score Coefficient (DSC) from 0.76 to 0.88. T1? reproducibility was high (COV < 0.05, intra-class correlation coefficient (ICC) = 0.85-0.97). Mean myocardial T1? value in healthy subjects was 63.5 ± 4.6 msec. There was good correspondence between late-gadolinium enhanced (LGE) MRI and increased T1? relaxation times in patients.

Conclusion

Single-shot, motion corrected, spin echo, spin lock MRI permits 2D T1? mapping in a breath-hold with good accuracy and precision.

SUBMITTER: Berisha S 

PROVIDER: S-EPMC4803208 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature