MR imaging of meniscal tears: narrow versus conventional window width photography.

Abstract

Narrow window width photography of magnetic resonance (MR) images of knee menisci is promoted as a useful tool in the detection of meniscal tears. To assess the diagnostic efficacy of this method, conventional and narrow window width MR images of 48 patients (96 menisci, 37 tears) were interpreted by two experienced observers. Images were graded on a five-point scale to enable receiver operating characteristic (ROC) curve analysis. The ROC curves constructed from the conventional window width interpretations were similar to those of the narrow window width interpretations for both observers. It was not possible to prove that the areas under the two curves were significantly different. This suggests that there is no globally significant improvement in the detection of meniscal tears when narrow window width images are used for interpretation.