표제지
목차
국문초록 9
I. 서론 11
II. 이론적 배경 13
1. CT의 정의 13
2. CT 재구성 알고리즘 14
1) 역투영법 14
2) 필터 보정 역투영(Filtered Back Projection, FBP) 15
3) 푸리에 변환 재구성(Fourier Transformation Reconsturction) 16
4) 반복적 재구성(Iterative Reconstruction, IR)법 16
3. 영상화질 및 흡수선량 측정 방법 26
1) CT치 (CT number) 26
2) 잡음(Noise) 26
3) 대조도 대 잡음비(Contrast to Noise Ratio, CNR) 27
4) 신호 대 잡음비(Signal to Noise Ratio, SNR) 28
5) 흡수선량 28
6) 등가선량 29
7) 유효선량 30
III. 연구 재료 및 방법 31
1. 연구 재료 31
1) 검사장비 31
2) 팬텀 35
3) OSLD Microstar Reading System(Optically Stimulated Luminescent Dosimeter, OSLD, MicrostarTM, Landauer Co. Glenwood, Illinois) 37
2. 연구 방법 38
1) 검사 조건 설정 38
2) 10세 팬텀을 이용한 주요 장기의 피폭 선량 측정 40
3) 영상 획득 42
3. 정량적 평가 44
4. 통계 분석 46
1) 일원 배치 분산분석(One-way ANOVA) 46
IV. 결과 47
1. 주요 장기의 심부 흡수선량 측정 47
2. 선량 평가 48
3. 화질 평가 49
1) CNR 49
2) SNR 51
V. 고찰 53
VI. 결론 56
참고문헌 57
Abstract 61
Table 1. Specification of inspection equipment (S Company) 31
Table 2. Specification of inspection equipment (G Company) 33
Table 3. The result of exposure dose survey using Phantom 38
Table 4. Scan parameter of CT study 40
Table 5. Measurement of absorption dose for major organs, unit mGy 47
Table 6. Comparison of CTDI, DLP by S, G Company 48
Table 7. Comparison of CNR by FBP, ADMIRE 50
Table 8. Comparison of CNR by FBP, ASIR-V. 50
Table 9. Comparison of SNR by FBP, ADMIRE 52
Table 10. Comparison of SNR by FBP, ASIR-V. 52
Figure 1. Principle of FBP 15
Figure 2. Principle of IRIS 18
Figure 3. Principle of SAFIRE 19
Figure 4. Principle of ADMIRE 20
Figure 5. Principle of ASIR 22
Figure 6. Principle of Veo 23
Figure 7. Principle of ASIR-V 24
Figure 8. FBP, ASIR-V, DLIR comparison 25
Figure 9. SIEMENS SOMATOM Force 32
Figure 10. GE healthcare Discovery CT-750HD 34
Figure 11. Model 706-G, CIRS, Norfolk, Virginia, USA 35
Figure 12. pediatric Anthropomorphic phantom model715 series 36
Figure 13. OSLD Microstar Reading System 37
Figure 14. Dose report (100 ㎸, 80 mAs CTDI) 39
Figure 15. Measurement of absorption dose using Model 706-G 41
Figure 16. Acquired a phantom image using S company equipment 42
Figure 17. Acquired a phantom image using G company equipment 43
Figure 18. Extracting images using IMAGE J 44
Figure 19. Setting the ROI in the phantom image 45