FAT-SUPPRESSED STIR SEQUENCES WITH AND WI THOUT CONTRAST-MEDIUM IN MRT OF ENT TUMORS

Fat suppressed STIR (short TI inversion recovery) sequences were compa red to plain an contrast enhanced T1-weighted SE-sequences of head and neck tumours. 19 patients underwent MR imaging on a 0.5 Tesla system (T5-II, Philips). STIR imaging parameters: TR/TE = 1000/20 ms, inversi on pulse 100 ms. All films were read by four radiologists. The image q uality was graded: score from 0 to 5, by means that grade 5 = optimal quality. Sensitivity was 89 % in STIR, 96% in SE-sequences. Tumour del ineation was graded good in the enhanced T1-weighted and enhanced fat suppression images. The unenhanced imaging was superior in STIR (STIR/ T1 = 2.8/2.43). The tumour contrast was best in contrast enhanced and plain STIR sequences (STIR contrast = 3.41), and in the contrast enhan ced T1-weighted SE (3.33). STIR almost equaled T1 post-contrast in res pect of tumour conspicuity, but the sensitivity was lower. STIR can be a supplement to SE, but cannot substitute T1 postcontrast. The combin ed use is expected to have the highest assessment value.