Publications [#269017] of G. Allan Johnson

Papers Published
  1. Spritzer, CE; Vogler, JB; Martinez, S; Garrett, WE; Johnson, GA; McNamara, MJ; Lohnes, J; Herfkens, RJ, MR imaging of the knee: preliminary results with a 3DFT GRASS pulse sequence., Ajr. American Journal of Roentgenology, vol. 150 no. 3 (March, 1988), pp. 597-603 [3257617], [doi] .

    The knees of 17 patients (18 extremities) with possible meniscal, cruciate ligament, and articular cartilage abnormalities were examined with a three-dimensional Fourier transform (3DFT), gradient-refocused acquisition in a steady state (GRASS) pulse sequence. Arthroscopic confirmation was available in all cases and was the standard for comparison. Thirteen of these extremities were also examined by using a two-dimensional Fourier transform spin-echo pulse sequence with a 2000-msec repetition time and 20- and 80-msec echo time. In these 13 cases, both pulse sequences correctly identified seven of eight meniscal abnormalities. However, interpretation of the 3DFT GRASS images resulted in fewer false-positive meniscal tears (three vs six). Cruciate ligament tears were detected more readily on the 3DFT GRASS images (six vs three with two possible tears on the spin-echo images). These preliminary findings suggest that the overall accuracy of MR imaging of the knee could be improved by including 3DFT gradient-refocused pulse sequences.