[Indirect MR arthrography in the diagnosis of rotator cuff lesions]

To determine the value of indirect MR arthrography in lesions of the rotator cuff, prospectively versus arthroscopy.

63 patients with suspected shoulder pathology were examined: oblique-coronary and axial T1w sequences, axial FLASH-2D sequences, furthermore oblique-coronary T2- and PD-weighted sequences were taken. After intravenous administration of 0.1 mmol Gd-DTPA/kilogram body weight and active motion of the shoulder T1w sequences were repeated. Signal intensities (SI) inside the tendon were quantitatively measured by the ROI technique (region-of-interest) and the percentual contrast-enhancement CE was calculated. In 32 patients the results were confirmed by surgical follow-up.

The mean SI measured in the supraspinous tendon were higher in lesions (degeneration, impingement, partial and total rupture), before as well as after contrast medium, compared to intact findings (p < 0.05). Similarly the percentual CE (p < 0.05) was higher. We detected 9 total ruptures and three impingements (for both sensitivity before/after Gd-DTPA 100%), furthermore 6 partial ruptures. Of the latter three were false positive and one false negative, leading to a sensitivity of 75% and a specificity of 50%.

The visualization of rotator cuff lesions can be optimized with indirect MR arthrography. The detection of partial ruptures remains faulty, because the exact demarcation of degenerative change and partial rupture is still difficult.