SPECT/CT 영상에서 에너지창 기반 산란보정과 CT 기반 산란보정 방법의 정량적 정확성 비교

• 영문명: The Comparison of Quantitative Accuracy between Energy Window-Based and CT-Based Scatter Correction Method in SPECT/CT Images
• 발행기관: 대한방사선과학회(구 대한방사선기술학회)
• 저자명: 김지현(Ji-Hyeon Kim) 이주영(Joo-Young Lee)
• 간행물 정보: 『방사선기술과학』방사선기술과학 제45권 제2호, 135~143쪽, 전체 9쪽
• 주제분류: 의약학 > 방사선과학
• 파일형태: PDF
• 발행일자: 2022.04.30

영문 초록

In SPECT image, scatter count is the cause of quantitative count error and image quality degradation. This study is to evaluate the accuracy of CT based SC(CTSC) and energy window based SC(EWSC) as the comparison with existing Non SC. SPECT/CT images were obtained after filling air in order to acquire a reference image without the influence of scatter count inside the Triple line insert phantom setting hot rod(99mTc 74.0 MBq) in the middle and each SPECT/CT image was obtained each separately after filling water instead of air in order to derive the influence of scatter count under the same conditions. For EWSC, 9 sub-energy windows were set additionally in addition to main energy window(140 keV, 20%) and then, images were acquired at the same time and five types of EWSC including DPW(dual photo-peak window)10%, DEW(dual energy window)20%, TEW(triple energy window)10%, TEW5.0%, TEW2.5% were used. Under the condition without fluctuations in primary count, total count was measured by drawing volume of interest (VOI) in the images of the two conditions and then, the ratio of scatter count of total counts was calculated as percent scatter fraction(% SF) and the count error with image filled with water was evaluated with percent normalized mean-square error(% NMSE) based on the image filled with air. Based on the image filled with air, %SF of images filled with water to which each SC method was applied is non scatter correction(NSC) 37.44, DPW 27.41, DEW 21.84, TEW10% 19.60, TEW5% 17.02, TEW2.5% 14.68, CTSC 5.57 and the scatter counts were removed the most in CTSC and %NMSE is NSC 35.80, DPW 14.28, DEW 7.81, TEW10% 5.94, TEW5% 4.21, TEW2.5% 2.96, CTSC 0.35 and the error in CTSC was found to be the lowest. In SPECT/CT images, the application of each scatter correction method used in the experiment could improve the quantitative count error caused by the influence of scatter count. In particular, CTSC showed the lowest %NMSE(=0.35) compared to existing EWSC methods, enabling relatively accurate scatter correction.

목차

Ⅰ. 서 론

Ⅱ. 대상 및 방법

Ⅲ. 결 과

Ⅳ. 고 찰

Ⅴ. 결 론

REFERENCES

키워드

단광자방출전산화단층영상 산란보정 에너지 창 정량적 정확성 핵의학 SPECT/CT Scatter Correction Energy Window Quantitative Accuracy Nuclear Medicine