What is the primary use of FLAIR MRI sequences?

What is the primary use of FLAIR MRI sequences?

• A. Detects acute blood flow velocity
• B. Detect edema, inflammation, and plaque
• C. Visualizes calcifications
• D. Maps diffusion of water

Answer: (B)

FLAIR sequences suppress the signal from cerebrospinal fluid, which makes brain tissue changes stand out more clearly. By nulling CSF, edema, inflammation, and demyelinating plaques near ventricles or along the surface of the brain become more conspicuous because the surrounding fluid is dark while pathological tissue remains bright on this T2-weighted type of image. This contrast is especially helpful for spotting white-matter lesions, such as those seen in multiple sclerosis, and for identifying edema from various causes. The other options relate to imaging features that are best seen with different techniques: detecting acute blood flow velocity uses Doppler methods, calcifications are best seen on CT or specific susceptibility sequences, and diffusion of water is mapped with diffusion-weighted imaging. In summary, the primary use of FLAIR is to detect edema, inflammation, and plaques by enhancing the visibility of pathological tissue near CSF.

FLAIR sequences suppress the signal from cerebrospinal fluid, which makes brain tissue changes stand out more clearly. By nulling CSF, edema, inflammation, and demyelinating plaques near ventricles or along the surface of the brain become more conspicuous because the surrounding fluid is dark while pathological tissue remains bright on this T2-weighted type of image. This contrast is especially helpful for spotting white-matter lesions, such as those seen in multiple sclerosis, and for identifying edema from various causes. The other options relate to imaging features that are best seen with different techniques: detecting acute blood flow velocity uses Doppler methods, calcifications are best seen on CT or specific susceptibility sequences, and diffusion of water is mapped with diffusion-weighted imaging. In summary, the primary use of FLAIR is to detect edema, inflammation, and plaques by enhancing the visibility of pathological tissue near CSF.