Improved dark blood late gadolinium enhancement (DB-LGE) imaging using an optimized joint inversion preparation and T2 magnetization preparation

Abstract

Purpose: To develop a dark blood–late gadolinium enhancement (DB-LGE) sequence that improves scar–blood contrast and delineation of scar region. Methods: The DB-LGE sequence uses an inversion pulse followed by T2 magnetization preparation to suppress blood and normal myocardium. Time delays inserted after preparation pulses and T2-magnetization-prep duration are used to adjust tissue contrast. Selection of these parameters was optimized using numerical simulations and phantom experiments. We evaluated DB-LGE in 9 swine and 42 patients (56 ± 14 years, 33 male). Improvement in scar–blood contrast and overall image quality was subjectively evaluated by two independent readers (1 = poor, 4 = excellent). The signal ratios among scar, blood, and myocardium were compared. Results: Simulations and phantom studies demonstrated that simultaneous nulling of myocardium and blood can be achieved by selecting appropriate timing parameters. The scar–blood contrast score was significantly higher for DB-LGE (P < 0.001) with no significant difference in overall image quality (P > 0.05). Scar–blood signal ratios for DB-LGE versus LGE were 5.0 ± 2.8 versus 1.5 ± 0.5 (P < 0.001) for patients, and 2.2 ± 0.7 versus 1.0 ± 0.4 (P = 0.0023) for animals. Scar–myocardium signal ratios were 5.7 ± 2.9 versus 6.3 ± 2.6 (P = 0.35) for patients, and 3.7 ± 1.1 versus 4.1 ± 2.0 (P = 0.60) for swine. Conclusions: The DB-LGE sequence simultaneously reduces normal myocardium and blood signal intensity, thereby enhancing scar–blood contrast while preserving scar–myocardium contrast. Magn Reson Med 79:351–360, 2018. © 2017 International Society for Magnetic Resonance in Medicine.