MR TOMOGRAPHY WITH FAST-STIR TECHNIQUE - OPTIMIZATION AND COMPARISON WITH OTHER SEQUENCES IN A 0.5 TESLA SYSTEM

One disadvantage of the STIR sequence in MRI is its long acquisition t ime. A TR shortening for acceleration requires shortening of the inver sion time depending upon the field strength. We optimized this ''fast- STIR'' technique at 0.5 T using calculations, phantom, volunteer, and patient measurements. This optimization procedure is transferable to o ther field strengths' The resulting sequence takes 4.5 minutes, fat is visualised signal-free. In the second part of our study we compared q uantitatively and qualitatively the signal intensities, contrast, and sensitivity towards artifacts of this sequence with that of convention al SE and GRE sequences in 21 patients with neoplastic, inflammatory a nd traumatic disorders of the musculoskeletal system. The fast-STIR se quence showed similar or better lesion contrast as SE in 100 % and as GRE in 88 %. Decreased spatial resolution and higher sensitivity towar ds pulsatile artifacts of the fast-STIR sequence were only minor drawb acks.