Comparison of Three-dimensional Isotropic T1-weighted Fast Spin-Echo MR Arthrography with Two-dimensional MR Arthrography of the Shoulder

Purpose: To determine the accuracy of a three-dimensional (3D) isotropic T1-weighted fast spin-echo (FSE) magnetic resonance (MR) sequence as compared with a conventional two-dimensional (2D) sequence in the diagnosis of rotator cuff tears and labral lesions. Materials and Methods: Institutional review board approval was obtained, and the informed consent requirement was waived. Forty-nine patients who had undergone direct or indirect shoulder MR arthrography with the 2D T1-weighted FSE sequence and the 3D isotropic T1-weighted FSE sequence and subsequent arthroscopy were included. Each MR imaging sequence was independently scored by two readers retrospectively for the presence of full-or partial-thickness tears of the supraspinatus (SST) and infraspinatus (IST) tendons and the subscapularis tendon (SCT) and labral lesions. Diagnostic performance based on each sequence type was compared by using the area under the receiver operating characteristic curve (AUC). Results: Arthroscopic findings enabled confirmation of the presence of 17 full-thickness SST-IST tears, 18 partial-thickness SST-IST tears, four full-thickness SCT tears, 17 partial-thickness SCT tears, and 17 labral lesions. The AUCs for the readers using the 3D T1-weighted FSE sequence versus those obtained with the 2D sequence were 0.771-0.989 versus 0.837-0.998 for reader A and 0.771-0.989 versus 0.797-0.989 for reader B in the detection of rotator cuff tears and 0.885 versus 0.897 for reader A and 0.895 versus 0.895 for reader B in the detection of labral lesions. The mean AUCs between the 2D and 3D sequences were not significantly different, with the exception of partial-thickness SCT tears for one reader. Conclusion: The accuracy of 3D isotropic FSE MR arthrography may be comparable with that of conventional 2D MR arthrography in the diagnosis of rotator cuff tears and labral lesions with a shorter imaging time.