Fast T2 Mapping Using Partially Spoiled Steady State Free Precession (T2-pSSFP)

Introduction. Only recently, an analytic solution for partial spoiling of the steady state of gradient echo sequences (pSSFP) was presented [1]. Radiofrequency phase cycling (RF spoiling) refers to a linear increment in the differential RF phase of consecutive excitation pulses φk − φk−1 = kφ, characterized by the phase shift increment φ. The steady state depends sensitively on φ, yielding SSFP-FID (FISP, FFE, ...) for φ = 0° and SPGR (FLASH, T1-FFE, ...) for φ=50° or 117°. It was been shown that for small TR and φ, the width of the transition from SSFP-FID to SPGR is inversely proportional to T2. Here, we make use of the approximate solution for partially spoiled SSFP sequences for small φ, to allow for fast 3D quantitative T2 mapping.