256 다중 검출기 전산화단층촬영에서 두개부 전용 팬톰을 이용한 분해능 파라메터와 재구성 필터의 영상 평가

국문 초록 (Abstract)

256 다중 검출기 전산화단층촬영 (multi detector computed tomography, MDCT)에서 두개부 전용 팬톰을 이용하여 분해능 파라메터와 재구성 필터의 영상 품질을 평가하고자 하였다. 사용한 장비는 256 MDCT 을 사용하였으며 philips system head phantom을 이용하여 Extended Brilliance Workspace에서 영상의 질 평가를 측정하였다. 장비에서 지원하고 있는 분해능 파라메터와 재구성 필터가 화질에 미치는 영향을 알아보기 위해서 검사조건을 512 × 512 matrix, 128 × 0.625 mm beam collimation, 120 kVp, 250 mAs, 0.5 sec, 250 mm field of view (FOV), 절편 두께와 절편 간격은 5 mm, 1.0 pitch로 동일하게 적용하였다. 분해능 파라메터은 ‘Standard’, ‘High’, ‘Ultrahigh’로 구분하여 적용하였으며, 재구성 필터는 A, B, C, D, UA, UB, UC 등으로 바꿔가면서 영상을 재구성하여 노이즈, 균일도, 직선성, 변조전달함수 (modulation transfer function, MTF)의 50%와 10%를 측정하였다. 그 결과 ‘High’ 분해능은 균일도, 직선성, MTF 50%와 10%에서 우수하였다. UA, UB 재구성 필터는 균일도와 노이즈 평가에서 양호했으며 ‘C재구성 필터는 직선성과 MTF 50%와 10%에서 양호하였다.

다국어 초록 (Multilingual Abstract)

The purpose of this study was to evaluate of resolution parameter and reconstitution filter in the 256 multi detector computed tomography(MDCT) by using the head phantom. We used 256 MDCT, and head phantom of philips system. We evaluated to image quality by using Extended Brilliance Workspace. The protocol were axial scan method with 120 kVp, 0.5 sec of rotation time, 5 mm of slice thickness and increment, 250 mm of field of view(FOV), 512 × 512 of matrix size, 1.0 of pitch, 128 × 0.625 mm of collimations. The resolution parameter was applied for Standard, High and Ultrahigh. The reconstitution filters were changed to seven type of A, B, C, D, UA, UB, UC. The assesment factors of image quality were the uniformity, the noise, the linearity and 50% and 10% of the modulation transfer function(MTF). Finally The good image quality in High resolution parameter showed at the uniformity, the linearity and 50% and 10% of MTF. The UA, UB reconstitution filter showed at the good image quality of the uniformity and the noise and C reconstitution filter showed at the same result of the linearity and 50% and 10% of MTF.

목차 (Table of Contents)

• 요약
• Abstract
• Ⅰ. 서론
• Ⅱ. 실험장비 및 방법
• Ⅲ. 결과
• Ⅳ. 고찰
• Ⅴ. 결과
• 참고문헌

참고문헌 (Reference)

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