TY - JOUR T1 - Optimization of sequence parameters in fast MR imaging of the brain with FLASH. JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 357 LP - 362 VL - 10 IS - 2 AU - T W Stadnik AU - R R Luypaert AU - E C Neirynck AU - M Osteaux Y1 - 1989/03/01 UR - http://www.ajnr.org/content/10/2/357.abstract N2 - Owing to the intrinsically complex behavior of the signal intensity of fast gradient-refocusing MR sequences, agreement as to the clinically most useful sequence parameters has not yet been reached. This study evaluates the FLASH (fast low-angle shot) sequence for gray-white matter differentiation on normal volunteers at 1.5 T. The FLASH gradient-echo sequence is essentially T1-dependent. For very fast imaging and T1 weighting, the following parameters yield the best results: a flip angle of 30-50 degrees with TR = 20 and TE = 10. To replace T1-weighted SE by the faster FLASH sequence, the best results are achieved by a flip angle of 70-120 degrees with TR = 150-300 and TE = 10 (or shorter, if possible). The most valuable proton-density aspect is achieved by a flip angle of 30 degrees with TR = 300 and TE = 16. ER -