원저 : Tc - 99m - MIBI 심근 SPECT 영상에서 재구성 필터에 의한 인위적 관류결손에 관한 연구 ( Artifactual Perfusion Defects due to the Parameters of Reconstruction Filter in Tc - 99m - MIBI Myocardial SPECT Images ) () |
Author |
곽철은(Cheol Eun Kwark),이경한(Kyung Han Lee),이동수(Dong Soo Lee),박용우(Yong Woo Park),정준기(June Key Chung),이명철(Myung Chul Lee),서정돈(Joung Don Seo),고창순(Chang Soon Koh), |
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Affiliation |
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Abstract |
Tc-99m-MIBI(Sestamibi) myocardial SPECT along with T1-
201 tomographic imaging has demonstrated wide
application and high image quality sufficient for the
diagnosis of myocardial perfusion defect, which
consequently reflects regional myocardial blood flow.
The qualitative values of myocardial SPECT with Tc-99m-
MIBI as well as the quantitative cases depend in some
degree on the reconstruction techniques of multiple
projections. Filtered backprojection(FBP) is the common
standard for reconstruction rather than the complicated
and time-consuming arithmetic methods. In FBP it is
known that the distribution of radioactivity in
reconstructed transverse slices varies with the
selected filter parameters such as cutoff frequencies
and order (Butterworth case). The cutoff frequencies
basically remove and decrease the true radioactive
distribution and alter the pixel counts, which lead to
underestimation of true counts in specific myocardial
regions. In this study, we have investigated the effect
of cutoff frequencies of reconstruction filter on the
artifactually induced perfusion defects, which are
often demonstrated near inferior and/or inferoseptal
cardiac walls due to the intense hepatic uptake of Tc-
99m-MIBI. A computerized method for identifying the
relative degree of artifactual perfusion defect and for
comparing those degrees along with the relative amount
of hepatic uptake to myocardium was developed and
patient images were studied to observe the quantitative
degree of underestimation of myocardial perfusion, and
to propose some reasonable thresh-old of cutoff
frequency in the diagnosis of perfusion defect
quantitatively. We concluded that from the quantitative
viewpoint cutoff frequencies may be used as high as
possible with the sacrifice of homogeneity of image
quality, and those frequencies lower than the common
0.3 Nyquist frequency would reveal severe degradation
of radio-active distribution near inferior and/or
inferoseptal myocardium when applying Butterworth or
low pass filter. |
Keyword |
Tc-99m-MIBI myocardial SPECT, Filtered backprajection, Artifactual perfusion defect, Cutoff frequency |
Full text Article |
28501414.pdf
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