Frequency-modulated bSSFP: A novel and time-efficient approach for multiparametric mapping

Motivation: Sampling a bSSFP profile using frequency-modulation (FM) is more time-efficient because steady-state preparation can be reduced, but the effect on multiparametric mapping is unknown. Goal(s): To demonstrate that FM bSSFP can be used to map relaxation times and proton density. Approach: FM and phase-cycled bSSFP data were acquired to obtain parametric maps in reference phantoms and in the human brain. Results: T1 and T2 quantification using FM bSSFP agreed with nominal values of the reference with R2=0.99 respectively. FM bSSFP yielded T1, T2 and proton density maps in the brain agreeing with phase-cycled bSSFP while being 55 seconds faster. Impact: Using frequency-modulated bSSFP as an alternative to phase-cycled bSSFP for biomarker quantification introduces new opportunities to accelerate the data acquisition. With steady-state preparation required only once, scan time is reduced, and transient state dead-time is minimized.