MUSCULOSKELETAL MR-IMAGING - TURBO (FAST) SPIN-ECHO VERSUS CONVENTIONAL SPIN-ECHO AND GRADIENT-ECHO IMAGING AT 0.5-TESLA

The value of T2-weighted fast spin-echo imaging of the musculoskeletal system was assessed in 22 patients with various neoplastic, inflammat ory, and traumatic disorders. Images were acquired with high echo numb er (i.e., echo train length) fast spin-echo (FSE; TR 2000 ms, effectiv e TE 100 ms, echo number 13, linear k-space ordering), conventional sp in-echo (SE; TR 2000 ms, TE 100 ms) and gradient-echo (GRE) sequences (TR 600 ms, TE 34 ms, flip angle 25 degrees). Signal intensities, sign al-to-noise ratios, contrast, contrast-to-noise ratios, lesion conspic uousness, detail perceptibility, and sensitivity towards image artifac ts were compared. The high signal intensity of fat on FSE images resul ted in a slightly inferior lesion-to-fat contrast on FSE images. Howev er, on the basis of lesion conspicuity, FSE is able to replace time-co nsuming conventional T2-weighted SE imaging in musculoskeletal MRI. In contrast, GRE images frequently showed superior lesion conspicuity. O ne minor disadvantage of FSE in our study was the frequent deteriorati on of image quality by blurring, black band, and rippling artifacts. S ome of these artifacts, however, can be prevented using short echo tra ins and/or short echo spacings.