An optimized 3D spoiled gradient recalled echo pulse sequence for hemorrhage assessment using inversion recovery and multiple echoes (3D SHINE) for carotid plaque imaging.

ABSTRACT

Intraplaque hemorrhage into the carotid atherosclerotic plaque has been shown to create instability and progression. We have developed an optimized 3D Spoiled Gradient recalled echo pulse sequence for Hemorrhage assessment using INversion recovery and multiple Echoes (3D SHINE) for carotid plaque imaging. The sequence was developed by incorporating multiecho acquisition to its clinically validated optimized single-echo counterpart 3D inversion recovery prepared fast spoiled gradient recalled sequence. With similar scan time (4 min), 3D spoiled gradient recalled echo pulse sequence for hemorrhage assessment using inversion recovery and multiple echoes maintained comparable high-resolution volumetric coverage, black-blood effect, contrast, signal-to-noise and contrast-to-noise ratios, and similar sensitivity and specificity in detecting whether intraplaque hemorrhage was present on an artery. The multiple echoes acquired with 3D SHINE allowed the estimation of intraplaque hemorrhage T*(2) and then the subsequent characterization of intraplaque hemorrhage (T*(2) for type I < 14 msec, and for type II > 14 msec). The type I intraplaque hemorrhage size estimated by 3D SHINE was significantly and positively correlated with the size estimated manually by an expert reviewer using the histology-validated multicontrast MRI technique (r = 0.836 ± 0.080, p < 0.001). With only one fast sequence, 3D SHINE can detect and characterize intraplaque hemorrhage that has previously required a multicontrast approach using a combination of black-blood T(1)-weighted, black-blood T(2)-weighted, and time-of-flight imaging techniques.