Optimization of Rapid Acquisition With Relaxation Enhancement (RARE) Pulse Sequence Parameters for F-19-MRI Studies

Materials and Methods: Relative SNR changes were theoretically calculated at given relaxation times (T-1, T-2) and mapped in RARE parameter space (TR, number of echoes, flip back pulse), at fixed acquisition times. T-1 and T-2 of KPF6 phantom samples (solution, agar mixtures, ex vivo perfused brain) were measured and experimental SNR values were compared with simulations, at optimal and suboptimal RARE parameter values.

Purpose: To optimize signal-to-noise ratio (SNR) in fast spin echo (rapid acquisition with relaxation enhancement [RARE]) sequences and to improve sensitivity in F-19 magnetic resonance imaging (MRI) on a 7T preclinical MRI system, based on a previous experimental evaluation of T-1 and T-2 actual relaxation times.