Fast fluid attenuated inversion-recovery (FLAIR) MRI in the assessment of intraaxial brain tumors

This study demonstrates the value of a fast fluid-attenuated inversion-reco very (FLAIR) technique in the assessment of primary intraaxial brain tumors , Twenty-one patients with primary intraaxial brain tumors were examined by T2-weighted, proton-density-weighted fast spin echo, fast FLAIR, and contr ast-enhanced T1-weighted spin echo using identical slice parameters, The im ages were evaluated using quantitative and qualitative criteria, Quantitati ve criteria were tumor-to-background and tumor-to-cerebrospinal fluid (CSF) contrast and contrast-to-noise ratio (CNR), The qualitative evaluation was performed as a multi-reader analysis concerning lesion detection, lesion d elineation, and image artifacts. In the qualitative evaluation, all readers found the fast FLAIR to be superior to fast spin echo in the exact delinea tion of intraaxial brain tumors (P <.001) and the delineation of enhancing and nonenhancing tumor parts. Fast FLAIR was superior in the delineation of cortically located and small lesions but was limited in lesions adjacent t o the ventricles. Fast FLAIR provided a significantly better tumor-to-CSF c ontrast and tumor-to-CSF CNR (P <.001), The tumor-to-background contrast an d tumor-to-background CNR of the fast FLAIR images were lower than those of Ta-weighted spin-echo images but higher than those of proton-density-weigh ted spin-echo images. FLAIR images had more image artifacts influencing the image interpretation in only two patients. Signal hyperintensities at the ventricular border were present in 92% of the patients. They are common fin dings in fast FLAIR and should be included into the image interpretation.