Evaluation of Knee Meniscal Injuries Using Panoramic MR Images

At many institutions, sagittal and coronal slice magnetic resonance imaging (MRI) is routinely used for knee examinations. Recently, MRI diagnosis for knee meniscal injuries has spread remarkably, and the diagnostic value of the procedure is almost established. We made panoramic images by reconstructing 3D data images along the form of the meniscus using curved cuts and multiplanar reconstruction (MPR). We assessed the usefulness of the panoramic images for evaluating meniscal injuries in 34 patients who had arthroscopic surgery after the MRI. MRI data were acquired in the axial plane using a double echo steady state (DESS). The presence of 30 meniscal tears, 5 anterior cruciate ligament tears, 2 posterior cruciate ligament tears, and 1 medial collateral ligament tear were confirmed by the arthroscopic surgery. Sensitivity, specificity and accuracy for medial meniscus was 100, 95 and 97% respectively, and for lateral meniscus was 93, 95 and 97% respectively. The meniscal tears were visible on the panoramic images, which showed the entire meniscus from the anterior to the posterior segment, so that the anatomical locations of the tear were indicated distinctly. Furthermore, the posterior segment was shown in detail on the panoramic images better than on the conventional plane images.