원저 : < 15O-H2O > 심근 양전자 단층 촬영에서 혈류 분포의 비균일성과 분배계수 ( The Heterogeneity of Flow Distribution and Partition Coefficient in < 15O-H2O > Myocardium Positron Emission Tomography ) () |
Author |
안지영(Ji Young Ahn),이동수(Dong Soo Lee),김경민(Kyung Min Kim),정재민(Jae Min Jeong),정준기(June Key Chung),신승애(Seung Ae Shin),이명철(Myung Chul Lee),고창순(Chang Soon Koh), |
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Affiliation |
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Abstract |
For estimation of regional myocardial blood flow with
O-15 water PET, a few modifications considering partial
volume effect based on single compartment model have
been proposed. In this study, we attempted to quantify
the degree of heterogeneity and to show the effect of
tissue flow heterogeneity on partition coefficient(λ)
and to find the relation between perfusable tissue
index(PTI) and λ by computer simulation using two
modified models. We simulated tissue curves for the
regions with homogeous and heterogenous blood flow over
a various flow range(0.2-4.0ml/g/min).Simulated
heterogeneous tissue composed of 4 subregions of the
same or different size of block which have different
homogeneous flow and different degree of slope of
distribution of blood flow. We measured the index
representing heterogeneity of distribution of blood
flow for each heterogeneous tissue by the constitution
heterogeneity(CH). For model I, we assumed that tissue
recovery coefficient (FMME) was the product of partial
volume effect(FMMF) and PTI. Using model I, PTI, flow,
and FMM were estimated. For model II, we assumed that
partition coefficient was another variable which could
represent tissue characteristics of heterogeneity of
flow distribution. Using model II PTI, flow and λ were
estimated. For the simulated tissue with homogeneous
flow, both models gave exactly the same estimates of
three parameters. For the simulated tissue with
heterogeneous flow distribution, in model I, flow and
FMM were correctly estimated as CH was increased
moderately. In model II, flow and λ were decreased
curvi-linearly as CH was increased. The degree of
underestimation of λ obtained using model II, was
correlated with CH. The degree of underestimation of
flow was dependent on the degree of underestimation of
λ. PTI was somewhat overestimated and did not change
according to CH. We conclude that estimated λ reflect
the degree of tissue heterogeneity of flow
distribution. We could use the degree of
underestimation of λ to find the characteristic
heterogeneity of tissue flow and use λ to recover the
underestimated flow. |
Keyword |
0-15 water PET, PTI, partition coefficient, flow heterogeneity |
Full text Article |
28502116.pdf
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