Bibliogr. s. 497

BACKGROUND: To evaluate the accuracy of high resolution ultrasound (USG) and MRI in the diagnosis of rotator cuff tears (RCT) and to determine if high resolution USG compares favorably in sensitivity and specificity to MRI in the diagnosis of rotator cuff injury. MATERIAL AND METHODS: In this prospective comparative study, 40 patients with clinically suspected rotator cuff tears underwent both ultrasound and MRI of the shoulder. Out of these 40 patients, 31 patients who had positive findings for rotator cuff tears on ultrasound and/or MRI were finally included in the study while the remaining 9 patients with negative or unrelated findings were excluded. The USG and MRI were interpreted by two radiologists experienced in musculoskeletal radiology and blinded to findings of each other. Comparison was done using MRI as a standard reference. RESULTS: The agreement between USG and MRI for diagnosis of RCTs was statistically excellent; USG showed a sensitivity of 86.7% and a specificity of 100% for full-thickness tears, and a sensitivity of 89.7% and a specificity of 98.8% for partial-thickness tears; observed accuracy for full thickness tears was 98.4% and 95.9% for partial thickness tears. The Kappa coefficient of association was 0.91 for full thickness tears and 0.90 for partial thickness tears. CONCLUSIONS: Considering the comparable diagnostic accuracy of USG and MRI, the former modality can be used as a first-line investigation for diagnosis of RCT. MRI should be used secondarily as a problem-solving tool either following an equivocal shoulder USG or for delineation of anatomy in cases where surgical correction is needed.