A prospective study on the detection of labral lesions by indirect MR-arthrography of the shoulder.

Purpose: Aim of this prospective study was the evaluation of signal-alterat ions of anatomic shoulder structures before and after intravenous applicati on of Gd-DTPA. Furthermore the tested clinical value of indirect MR-arthrog raphy in detecting labral lesions was tested. Material and Methods: 52 pati ents with suspected shoulder injury were examined on a 1.5T system: Sequenc es were T(1-)weighted axial and oblique-coronary, additionally oblique-coro nary T-2-weighted, PD-weighted- and axial FLASH-2D-Sequences. After intrave nous injection of contrast medium T-1-weighted sequences were repeated. Sig nalintensities (S1) of anatomic structures were measured by ROI-technique, the percentual contrast-enhancement (CE) and alterations in SNR (sig- nal-n oise-ratio) and CNR (contrast-noise-ratio) were calculated. Labral tears we re graded by three observers, their results could be confirmed by arthrosco py or open surgery in 24 patients. Results: Contrast-enhancement was shown in all structures, most remarkable in the joint cavity. In pathologic findi ngs of the labrum the SI and CE were significantly higher compared to intac t strictures(p < 0.05). Sensitivity and specificity in the detection of lab ral tears were 70% and 71.4% whithout contrast media, respectively 100% and 71,4% with indirect arthrography. Conclusions: The indirect arthrography i mproves the signal parameters of the structures. The detection of labral le sions is improved, but still remains difficult.