Turbo-FLAIR sequence in brain MRI

To compare a turbo-FLAIR sequence with Proton Density (PD) and T2- weighted Turbo Spin-Echo (TSE) sequences in several different brain diseases, 276 MRI examinations were performed on a 1.0 Tesla system. The positive cases were assessed for lesion detection and lesion conspicuity. Four quantitative criteria were also used to compare the contrast of the two techniques: lesion to background contrast, lesion to background contrast to noise ratio (CNR), lesion to Cerobrospinal fluid (CSF) contrast, lesion to CSF contrast to noise ratio. The turbo FLAIR sequence was found to be superior to PD and T2- weighted TSE for lesion detection: this sequence detected more lesions in 74 patients than PD and in 42 patients than T2, but missed some subtentorial lesions. For lesion conspicuity turbo-FLAIR was judged equivalent to PD and T2-weighted TSE respectively in 27% and 45% of the cases and better in 71% and 53% of the cases. Lesion to background contrast and lesion to background CNR were found to be significantly greater for turbo-FLAIR than for PD (p<0.001). Compared with T2-weighted TSE, turbo-FLAIR showed a significantly higher lesion to background contrast (p<0.001) and inferior lesion to background CNR (p<0.001). Our study indicates that turbo-FLAIR can replace PD TSE scans in most cases and can be used as a first choice sequence for cerebrovascular diseases, multiple sclerosis and for the evaluation of gliosis.