Objective: This study was performed to determine whether a modified version of the classic STIR sequence provides similar information about the integrity of the rotator cuff tendon as the commonly used fat-suppressed T2-weighted fast spin-echo sequence.
Subjects and methods: Sixty-one consecutive MRI examinations of the shoulder in 57 patients were performed using a coronal oblique T1-weighted spin-echo sequence, a modified version of the STIR sequence, and a fat-suppressed T2-weighted fast spin-echo sequence. Three reviewers independently assessed the rotator cuff tendon using the coronal oblique modified inversion recovery sequence and T1-weighted spin-echo sequence. After a minimum of 4 weeks, reviewers assessed the rotator cuff tendon using the fat-suppressed T2-weighted fast spin-echo sequence and T1-weighted spin-echo sequence. The kappa statistic was used to measure the degree of concordance between interpretations when each sequence was used independently. The conditional probability that a full- and a partial-thickness tear would be diagnosed on both sequences was calculated. Image quality was assessed in a side-by-side comparison.
Results: The overall weighted kappa score was 0.82, which indicates excellent concordance between the two sequences. If a full-thickness tear of the rotator cuff tendon was found on the fat-suppressed T2-weighted fast spin-echo sequence, there was a 94.1% probability that the same conclusion would be reached using the modified inversion recovery sequence. If a partial-thickness tear was found on the fat-suppressed T2-weighted fast spin-echo sequence, there was an 80.3% probability that the same conclusion would be reached with the modified inversion recovery sequence. Fat suppression in the modified inversion recovery sequence was superior to that in the T2-weighted fast spin-echo sequence in 26-39% of the examinations.
Conclusion: The modified inversion recovery sequence and fat-suppressed T2-weighted fast spin-echo sequence provide similar information about the integrity of the rotator cuff tendon.