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Digital Contents Society (한국디지털콘텐츠학회)
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The usability of the image according to the frequency encoding gradient direction conversion in fixation using the non magnetic metal screw

비 자성 금속 screw를 이용한 고정술에서 주파수 부호화 경사 방향 변환에 따른 영상의 유용성

  • Received : 2010.11.21
  • Accepted : 2011.03.30
  • Published : 2011.03.31
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Abstract

Because of causing the geometrical transformation of the magnetic field, the patient implementing the fixation using the nonmagnetic metal screw causes the magnetic susceptibility artifact at an image. Thus, in this research, the distortion measure of the image according to the frequency oblique direction conversion tried to be compared in the magnetic susceptibility artifact occurence. First, the itself phantom inserting the nonmagnetic metal screw of the titanium component was made and the region of interest was set up and the frequency oblique direction the anterior - back side was converted to the right-to-left direction in the axial image and a right-to-left was converted to the upper side - bottom side in the coronal plane and the upper - bottom side was converted to the anterior - back side in the sagittal plane and the distortion measure of the region of interest was compared, it observed. In a result, when converting the frequency oblique direction, the distortion difference of the region of interest could be confirmed and it is considered to enhance the diagnostics efficiency changing the oblique direction appropriately.

비 자성 금속 screw를 이용한 고정술을 시행한 환자를 대상으로 검사하는 자기공명영상에서는 자장의 기하학적 변형을 일으켜 영상에 자화율 인공물을 유발시킨다. 이에 본 연구에서는 자화율 인공물 발생 시 주파수 경사 방향 변환에 따른 영상의 왜곡 정도를 비교, 확인하고자 하였다. 우선 티타늄 성분의 비 자성 금속 screw을 삽입한 자체 팬텀을 제작하여 관심영역을 설정하고 주파수 경사 방향을 축상면에서는 전측-후측을 우측-좌측 방향으로 변환하였고 관상면에서는 우측-좌측을 위측-아래측으로 변환하였고 시상면에서는 상측-하측을 전측-후측으로 변환하여 관심영역의 왜곡 정도를 비교, 관찰 하였다. 결과적으로 주파수 경사 방향을 변환 하였을 때 관심 영역의 왜곡차이를 확인 할 수 있으며 향후 경사 방향을 적절하게 변경함으로써 진단적 효율을 높일 수 있을 것으로 사료된다.

Keywords

References

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