Comparison of fast spin-echo versus conventional spin-echo MRI for evaluating meniscal tears

OBJECTIVE. We compare sensitivities of conventional spin-echo and fast spin-echo sequences in the evaluation of meniscal tears. Furthermore, we reevaluate the results from prior studies comparing these two sequences to understand why there are differing conclusions regarding the efficacy of fast spin-echo sequences as a commensurate replacement for conventional spin-echo sequences. MATERIALS AND METHODS. We used records from a control group of 64 patients (128 menisci) who had undergone arthroscopy to determine the sensitivity of conventional spin-echo sequences for detecting meniscal tears. Two hundred sixteen consecutive patients (432 menisci) were then imaged using conventional spin-echo and fast spin-echo sequences to evaluate for meniscal tears. Both sequences were proton density-weighted with fat suppression. RESULTS. Of the 432 menisci, 170 tears were detected on conventional spin-echo imaging. Only 128 tears were detected on the fast spin-echo sequence. The sensitivities of conventional spin-echo and fast spin-echo imaging were found to be 93% and 80%, respectively. In addition, findings from conventional spin-echo and fast spin-echo sequences were discordant for 72 menisci (17%, p < 0.01). CONCLUSION. The sensitivities of conventional spin-echo and fast spin-echo imaging for detecting meniscal tears have been shown to be greater than 90% and approximately 80%, respectively. However, some authors advocate substituting conventional spin-echo imaging with fast spin-echo imaging. We urge the abandonment of fast spin-echo imaging for evaluating meniscal tears because a loss of greater than 10% in sensitivity is unacceptable.