Simultaneous T and T Mapping of the Carotid Plaque (SIMPLE) with T and Inversion Recovery Prepared 3D Radial Imaging

Purpose: To propose a technique that can produce different T and T contrasts in a single scan for simultaneous T and T mapping of the carotid plaque (SIMPLE).

Methods: An interleaved 3D golden angle radial trajectory was used in conjunction with T preparation with variable duration (TE ) and inversion recovery pulses. Sliding window reconstruction was adopted to reconstruct images at different inversion delay time and TE for joint T and T fitting. In the fitting procedure, a rapid B correction method was presented. The accuracy of SIMPLE was investigated in phantom experiments. In vivo scans were performed on 5 healthy volunteers with 2 scans each, and on 5 patients with carotid atherosclerosis.

Results: The phantom T and T estimations of SIMPLE agreed well with the standard methods with the percentage difference smaller than 7.1%. In vivo T and T for normal carotid vessel wall were 1213 ± 48.3 ms and 51.1 ± 1.7 ms, with good interscan repeatability. Alternations of T and T in plaque regions were in agreement with the conventional multicontrast imaging findings.

Conclusion: The proposed SIMPLE allows simultaneous T and T mapping of the carotid artery in less than 10 minutes, serving as a quantitative tool with good accuracy and reproducibility for plaque characterization.