인체 각 부위의 PET/MRI와 PET/CT의 SUV 변화

• 영문명: Comparison of SUV for PET/MRI and PET/CT
• 발행기관: 대한핵의학기술학회
• 저자명: 김재일(Jae Il Kim) 전재환(Jae Hwan Jeon) 김인수(In Soo Kim) 이홍재(Hong Jae Lee) 김진의(Jin Eui Kim)
• 간행물 정보: 『핵의학기술』Vol.17 No.2, 10~14쪽, 전체 5쪽
• 주제분류: 의약학 > 방사선과학
• 파일형태: PDF
• 발행일자: 2013.11.30

영문 초록

Purpose: Due to developed simultaneous PET/MRI, it has become possible to obtain more anatomical image information better than conventional PET/CT. By the way, in the PET/CT, the linear absorption coefficient is measured by X-ray directly. However in case of PET/MRI, the value is not measured from MRI images directly, but is calculated by dividing as 4 segmentation μ-map. Therefore, in this paper, we will evaluate the SUV's difference of attenuation correction PET images from PET/MRI and PET/CT. Materials and Methods: Biograph mCT40 (Siemens, Germany), Biograph mMR were used as a PET/CT, PET/MRI scanner. For a phantom study, we used a solid type ⁶⁸Ge source, and a liquid type ¹⁸F uniformity phantom. By using VIBE-DIXON sequence of PET/MRI, human anatomical structure was divided into air-lung-fat-soft tissue for attenuation correction coefficient. In case of PET/CT, the hounsfield unit of CT was used. By setting the ROI at five places of each PET phantom images that is corrected attenuation, the maximum SUV was measured, evaluated %diff about PET/CT vs. PET/MRI. In clinical study, the 18 patients who underwent simultaneous PET/CT and PET/MRI was selected and set the ROI at background, lung, liver, brain, muscle, fat, bone from the each attenuation correction PET images, and then evaluated, compared by measuring the maximum SUV. Results: For solid ⁶⁸Ge source, SUV from PET/MRI is measured lower 88.55% compared to PET/CT. In case of liquid ¹⁸F uniform phantom, SUV of PET/MRI as compared to PET/CT is measured low 70.17%. If the clinical study, the background SUV of PET/MRI is same with PET/CT's and the one of lung was higher 2.51%. However, it is measured lower about 32.50, 40.35, 23.92, 13.92, 5.00% at liver, brain, muscle, fat, femoral head. Conclusion: In the case of a CT image, because there is a linear relationship between 511 keV γ-ray and linear absorption coefficient of X-ray, it is possible to correct directly the attenuation of 511 keV γ-ray by creating a μmap from the CT image. However, in the case of the MRI, because the MRI signal has no relationship at all with linear absorption coefficient of γ-ray, the anatomical structure of the human body is divided into four segmentations to correct the attenuation of γ-rays. Even a number of protons in a bone is too low to make MRI signal and to localize segmentation of μ-map. Therefore, to develope a proper sequence for measuring more accurate attenuation coefficient is indeed necessary in the future PET/MRI.

목차

서론

실험재료 및 방법

결과

결론

REFERENCES

키워드

PET/MRI PET/CT SUV Attenuation correction