3-dimensional fluid-attenuated inversion recovery (3D-FLAIR) detected the highest number of infratentorial multiple sclerosis (MS) lesions compared to T2-weighted spin echo (T2-SE) and 2D-FLAIR, according to a recent study. Furthermore, investigators found that the 3D-FLAIR sequence addresses the disadvantage of poor infratentorial lesion detection on 2D, while still maintaining the advantage over T2-SE in the detection of lesions adjacent to the cerebrospinal fluid. 2 board-certified radiologists independently reviewed and counted infratentorial lesions from 85 brain MRIs in patients with clinically definite MS and concurrent 3D, 2D-FLAIR, and T2-SE sequences. Contrast-to-noise ratios (CNRs) and signal-to-noise ratios (SNRs) were measured for 25 MRIs. They found:

• The number of lesions on 3D-FLAIR was significantly higher than those on 2D and T2-SE.
• Results of CNRs and SNRs were overall mixed and predominantly not concordant with lesion count findings, with T2-SE demonstrating the highest SNR and CNR of lesion compared with white matter but the lowest CNR of lesion compared with gray matter.