Which statement about STIR sequences is correct?

Which statement about STIR sequences is correct?

• A. STIR sequences visualize calcifications
• B. STIR is a water-sensitive MRI sequence that visualizes edema
• C. STIR measures atomic density
• D. STIR sequences are used in CT

Answer: (B)

STIR is an MRI technique that uses an inversion pulse to cancel fat signal, making water-containing tissues stand out. By suppressing fat, edema—which has increased free water—appears bright on these images, so STIR is especially good at visualizing edema and related pathology. Calcifications are better seen on CT and MRI doesn’t measure atomic density directly; calcifications often appear as signal voids rather than as a edema-like bright signal. STIR is an MRI sequence, not something used in CT.

STIR is an MRI technique that uses an inversion pulse to cancel fat signal, making water-containing tissues stand out. By suppressing fat, edema—which has increased free water—appears bright on these images, so STIR is especially good at visualizing edema and related pathology. Calcifications are better seen on CT and MRI doesn’t measure atomic density directly; calcifications often appear as signal voids rather than as a edema-like bright signal. STIR is an MRI sequence, not something used in CT.