Gradient-recalled-echo technique

Wang SF, Cheng HC et al. (1999) Fat-suppressed three-dimensional fast spoiled gradient-recalled echo imaging a modified FS 3D SPGR technique for assessment of patellofemoral joint chondromalacia. Clin Imaging 23 177-180... 

While morphologic MRI with regard to mass assessment, detailed soft tissue differentiation, and cardiac morphology, is mainly carried out on T1-weighted or T2-weighted fast spin-echo (FSE) techniques, the majority of todays applications is covered with the use of gradient-recalled-echo (CRE) techniques. 

Figure 6 Magnetization transfer technique. (A) Two-pool model used for the evaluation. This is certainly a simplification of reality, although imaging data quality does not justify further elaboration. (B) MTC imaging sequence. A gradient-recalled echo data acquisition is used once more. The spoiler shown is used to dephase residual transverse magnetization after the end of the off-resonance irradiation period (of length t). Practical sequences of all types use pulses like this to eliminate the unwanted signals from spins pursuing complex patterns of excitation and recovery.

T2 is the transverse relaxation time measured using gradient-recalled, rather radiofrequency (RF)-recalled echoes (37). The RF technique (T2) cancels some of the inhomogeneity-induced relaxation and, therefore, T2 [Pg.51]

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