We compared the post-debridement size of rotator cuff tears determined from surgical findings with those measured by MRI. The subjects were 20 patients (21 shoulders) with a complete rotator cuff tear who underwent MRI before surgery. Seven of the patients were men and 13 were women. Sixteen tears involved the right shoulder and five involved the left one. The mean age of the patients was 65.1±8.1(SD) years, with a range of 52-78 years. MRI was performed with a superconducting Shimadzu 1.0-T Magnex 100 HP. The distance between the high-signal regions was measured in the oblique coronal and the oblique sagittal planes of T2-weighted image of fast spin echo technique (fast T2-weighted image)and T2*-weighted image of gradient echo technique was compared with the post-debridement tear dimensions measured during surgery. The mean difference between the operative findings and the values measured with MRI was 10.1±9.2mm for fast T2-weighted images and 4.6±9.1mm for T2-weighted images obtained in the oblique coronal plane. The mean differences obtained using oblique sagittal images were 9.1±5.7mm and 2.7±7.0mm, respectively. Our findings indicate that T2*-weighted image is useful for estimating the post-debridement size of rotator cuff tears.
