The Usefulness of STIR Image in Breast MRI

ABSTRACT

PURPOSE: To assess the usefulness of STIR (short tau inversion recovery) imaging in breast MRI (magnetic resonance imaging). MATERIALS AND METHODS: We retrospectively reviewed T1- and T2-weighted (T1WI, T2WI), STIR, and dynamically enhanced images of 44 pathologically confirmed breast lesions (benign, 13; malignant, 31) in 36 patients. We selected the dynamically image which best depicted a particular lesion, and then made hard copy of the corresponding T1WI, T2WI, and STIR images. Using the dynamically enhanced image as a standard, we analysed these in terms of parenchymal pattern, lesion detectability, differentiation between benign and malignant lesions, extent, multifocality, and the ductal system. The results were statistically analyzed. RESULTS: In 33 of 44 cases (75%), detectability was greater at STIR imaging than at T1- and T2WI, especially in fibrofatty or fatty breast (14/14 cases, p<0.05). STIR images did not always differentiate between benign and malignant lesions, and extent (50%) and multifocality (46%) were commonly exaggerated compared with T1- and T2WI. In 18 of 44 cases (41%), STIR images suggested the presence of ductal structures. CONCLUSION: For the detection of lesions, STIR imaging was more useful than T1- and T2WI, though STIR did not differentiate between benign and malignant lesions. The extent and multifocality of a lesion were exaggerated on STIR images, compared with T1- and T2WI.