Magnetic Resonance in Medicine
Ex Vivo Measurement of Human Blood T 1 at 5 T : Dependence on Hematocrit and Oxygenation
ABSTRACT Purpose To determine human blood longitudinal relaxation time (T 1 ) ex vivo at 5 T using modified Look‐Locker inversion recovery (MOLLI), and to evaluate its dependence on hematocrit (Hct) and oxygenation ( Y ). Methods A MOLLI 5(3)3 protocol was simulated across T 1 values of 1000–3000 ms to optimize the sampling interval. Aqueous gadolinium phantoms were scanned using optimized MOLLI and multi‐inversion‐time recovery spin echo (IR‐SE) acquisitions to derive a calibration equation. Arm venous blood from …