TY - JOUR T1 - FLAIR<sup>2</sup>: A Combination of FLAIR and T2 for Improved MS Lesion Detection JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. DO - 10.3174/ajnr.A4514 AU - V. Wiggermann AU - V. Hernández-Torres AU - A. Traboulsee AU - D.K.B. Li AU - A. Rauscher Y1 - 2015/10/08 UR - http://www.ajnr.org/content/early/2015/10/08/ajnr.A4514.abstract N2 - BACKGROUND AND PURPOSE: FLAIR and double inversion recovery are important MR imaging scans for MS. The suppression of signal from CSF in FLAIR and the additional suppression of WM signal in double inversion recovery improve contrast between lesions, WM and GM, albeit at a reduced SNR. However, whether the acquisition of double inversion recovery is necessary is still debated. Here, we present an approach that allows obtaining CSF-suppressed images with improved contrast between lesions, WM and GM without strongly penalizing SNR.MATERIALS AND METHODS: 3D T2-weighted and 3D-FLAIR data acquired from September 2014 to April 2015 in healthy volunteers (23.4 ± 2.4 years of age; female/male ratio, 3:2) and patients (44.1 ± 14.0 years of age; female/male ratio, 4:5) with MS were coregistered and multiplied (FLAIR2). SNR and contrast-to-noise measurements were performed for focal lesions and GM and WM. Furthermore, data from 24 subjects with relapsing-remitting and progressive MS were analyzed retrospectively (52.7 ± 8.1 years of age; female/male ratio, 14:10).RESULTS: The GM-WM contrast-to-noise ratio was by 133% higher in FLAIR2 than in FLAIR and improved between lesions and WM by 31%, 93%, and 158% compared with T2, DIR, and FLAIR, respectively. Cortical and juxtacortical lesions were more conspicuous in FLAIR2. Furthermore, the 3D nature of FLAIR2 allowed reliable visualization of callosal and infratentorial lesions.CONCLUSIONS: We present a simple approach for obtaining CSF suppression with an improved contrast-to-noise ratio compared with conventional FLAIR and double inversion recovery without the acquisition of additional data. FLAIR2 can be computed retrospectively if T2 and FLAIR scans are available.AbbreviationsCNRcontrast-to-noise ratioDIRdouble inversion recovery ER -