Diffusion Weighted Imaging in Musculoskeletal MRI: Analysis on Optimal Number of Excitations Providing better Differentiation of Maglignant Tumor

악성종양의 감별진단을 위한 근골격의 확산강조영상 검사 시 최적의 여기횟수

  • 최관우 (서울아산병원 영상의학과)
  • Received : 2018.07.23
  • Accepted : 2018.08.09
  • Published : 2018.08.28


The purpose of this study was to determine the optimal number of excitations(NEX) of diffusion weighted imaging(DWI) which is clinically useful in patients with musculoskeletal diseases while the scan time is relatively long. In this study, 30 patients underwent knee MRI using diffusion weighted image sequence using b values targeted on the bone and muscle. The NEX were varied from 1 to 5 and the ADC values were measured and analyzed. As a result of the study, 4 NEX and 2 NEX showed an statistically identical effect with the existing NEX on the bone and muscle diffusion weighted images, respectively. Also, it proved that the scan time could be significantly reduced by 21.2 % and 59.6 % compared to the established NEX which meant the optimal NEX could replace the existing NEX. In conclusion, applying the optimal NEX on the musculoskeletal bone and soft tissue DWI could improve the problems caused by the long scan time.


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