Purpose: To determine the effect of decreasing the field of view (FOV) on the accuracy of MR for diagnosing rotator cuff tears.
Material and methods: One hundred shoulder MR scans with surgical correlation were evaluated for the presence or absence of a cuff tear. The sensitivity and specificity of MR relative to the surgical results were determined for the 59 patients scanned with a 24-cm FOV, and the 41 patients scanned with an 18-cm FOV. All other imaging parameters including acquisition time were identical. The sensitivity and specificity of the two groups were compared using a t-test.
Results: The specificity of MR for diagnosing a rotator cuff tear improved from 0.65 for the 24-cm FOV group to 0.89 for the 18-cm FOV group (P = 0.04). The sensitivity changed from 0.91 to 0.96 (P = 0.25).
Conclusion: Reducing the FOV from 24 cm to 18 cm results in a statistically significant improvement in specificity of MR for diagnosing rotator cuff tears.