Simultaneous Non-contrast Angiography and intraPlaque hemorrhage (SNAP) imaging for carotid atherosclerotic disease evaluation

摘要

A Simultaneous Non-contrast Angiography and intraPlaque hemorrhage (SNAP) MR imaging technique is proposed to detect both luminal stenosis and hemorrhage in atherosclerosis patients in a single scan. 13 patients with diagnosed carotid atherosclerotic plaque were recruited after informed consent. All scans were performed on a 3T MR imaging system with SNAP, 2D time-of-flight (TOF) and magnetization-prepared 3D rapid acquisition gradient echo (MP-RAGE) sequences. The SNAP sequence utilized a phase sensitive acquisition, and was designed to provide positive signals corresponding to intraplaque hemorrhage (IPH) and negative signals corresponding to lumen. SNAP images were compared to TOF images to evaluate lumen size measurements using linear mixed models and the intraclass correlation coefficient (ICC). IPH identification accuracy was evaluated by comparing to MP-RAGE images using Cohen’s Kappa. Diagnostic quality SNAP images were generated from all subjects. Quantitatively, the lumen size measurements by SNAP were strongly correlated (ICC=0.96, p<0.001) with those measured by TOF. For IPH detection, strong agreement (κ=0.82, p<0.001) was also identified between SNAP and MP-RAGE images. In conclusion, a Simultaneous Non-contrast Angiography and intraPlaque hemorrhage (SNAP) imaging technique was proposed and shows great promise for imaging both lumen size and carotid intraplaque hemorrhage with a single scan.