Usefulness of Fat-Suppressed Turbo SE MR Imaging for the Evaluation of Meniscal Tears

ABSTRACT

PURPOSE: Suppression of the relatively high signal intensity of fat leads to more efficient use of thedynamic range for display of tissue contrast. In order to evaluate meniscal tears, we compared a fat-suppressedturbo spin-echo(FSTSE) sequence with turbo SE(TSE). MATERIALS AND METHODS: One hundred and seven knees in 103consecutive patients referred for MR study of the knee were imaged using both FSTSE and TSE sequence. The turbo SEsequence provided proton density-weighted and T2-weighted images (dual echo technique) with an effectiveecho-train length of five. For fat-suppression, a frequency-selective chemical presaturation pulse was applied.Forty-two knees (84 menisci) were studied arthroscopically and the findings were taken as the reference standard.FSTSE and TSE images were reviewed retrospectively by two radiologists. Next, for each patient, the quality ofFSTSE and TSE images was compared;the former were scored by each reviewer as either superior to, equal to, orinferior to TSE images. RESULTS: Among the 214 menisci evaluated, the results of FSTSE and TSE imaging were verysimilar (kappa index 0.87). Twenty four tears were found during arthroscopy in 84 menisci. FSTSE imaging was moresensitive than TSE (96% versus 83%), though specificity was equal(98%). Among the 107 cases, FSTSE images wererated by both observers as superior to TSE images for overall quality and visualization of the meniscus itself.CONCLUSION: For the evaluation of meniscal tears, FSTSE sequences were more sensitive than those obtained withTSE, and their image quality was superior. For the study of meniscus tears among a large population, FSTSE istherefore more useful than TSE.