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In the view of the identity of Cheoyong Cultural Festival of Ulsan (삼국유사 「처용랑망해사(處容郞望海寺)」조 깊이 읽기 - 울산광역시 처용문화제의 정체성과 관련하여 -)

  • Kang, seog keun
    • (The) Research of the performance art and culture
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    • no.32
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    • pp.465-488
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    • 2016
  • This paper attempts to read in different ways and to interpret newly on Cheoyongrang mhang-hae-sa in "Sam-guk-yu-sa". Ulsan have held Cheoyong Cultural Festival for 47 times according to "Sam-guk-yu-sa". However, there have been a frequent identity crisis about Cheoyong Cultural Festival because of controversial issue about Cheoyong, This paper interpretate Cheoyongrang mhang-hae-sa newly to overcome these crisis, Cheoyong's dancing and retreating was not the resignation and tolerance, but the treat and warning, as the dance of Namsansin god of Posukjeong, Buk-acksin god of Keumkangryung and Jisin god of Dongryejeon was the warning of Silla's ruination. 'The Mhang' of Mhang-he-sa temple should be interpreted not as 'watch' but 'fifteen days'. Mhang-he means the roads buried in darkness and vanished had become a sea. The name of Shin-bhang-sa temple means Gae-un-po province of Ulsan had become 'the newly purified region' because of the inspection of King Heon-ghang. The main keyword of Cheoyongrang mhang-hae-sa is 'Byuk-sa-jin-gyung'. 'Byuk-sa-jin-gyung' means to repel the impious and pray the pleasure. The purpose of the personal Gut and national Gut, Narae, was also 'Byuk-sa-jin-gyung'. The reinvented bridal room with a fresh life was like the world of Byuk-sa-jin-gyung. The dance of God Sa-bhang was, as well the desperate desire to New Silla. Cheoyong was a shaman with a superior authority who set up the power to foresee to the god of smallpox. The image of Cheoyong at is not the resignation and tolerance, but the foresight and authority. Therefore, the slogan of Cheoyong Cultural Festival, the resignation and tolerance, should be reexamined. The new Cheoyong Cultural Festival should adopt the concept of foresight and authority and Byuk-sa-jin-gyung. Cheoyong Cultural Festival, have been held for 49times, often had identity problems. The identity of Cheoyong have been misinterpreted as the resignation and tolerance. The slogan of Cheoyong Cultural Festival should be reexamined. The new Cheoyong Cultural Festival should adopt the concept of foresight and authority and Byuk-sa-jin-gyung.

Ki Ho School of Neo-Confucianism on Yi Xue Qi Meng in Later Chosun Period (조선후기 기호성리학파의 역학계몽 이해)

  • Yi, Suhn Gyohng
    • The Journal of Korean Philosophical History
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    • no.35
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    • pp.275-308
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    • 2012
  • This article aims to investigate the studies of Yi Xue Qi Meng(易學啓蒙) performed by the researchers of Neo-Confucianism in Ki Ho region in later Chosun period. Philologically speaking, these studies were mainly performed by Han Won Jin and his colleagues. While the study of Yi Hwang(李滉)'s Qi Meng Zhuan Yi(啓蒙傳疑) performed by the researchers of Toegye(退溪) School lasts from the end of the sixteenth century to the nineteen's century, the Ki Ho(畿湖) scholars' study of Yi Xue Qi Meng are centered in the eighteenth century and hardly any significant work on this text is found before and after this century. In order to single out the distinctive features of Ki Ho School of Neo-Confucianism, this article examines three subjects the Ki Ho scholars delved into: (i) their theory of Tai Ji(太極), (ii) their theory of He-Tu(河圖) and the formation of eight trigrams, and (iii) the so-called Wu Wei Xiang De Shuo(五位相得說) discussed in one of the sections in Yi Xue Qi Meng titled the Source of He-Tu and Luo Shu[本圖書]. The Ki Ho scholars are remarkable in interpreting Tai Ji in Yi Xue Qi Meng in the context of the theory of Li-Qi and the theory of human nature. There are differences in opinion among the Ki-Ho scholars with regard to the relation between He-Tu and the formation of eight trigrams. Eventually, they withhold Zhu Xi(朱熹) and Hu Fang Ping(胡方平)'s attempt to synthesize He-Tu, the rectangular diagram of Fu Xi(伏羲)'s eight trigrams, and the circular diagram of Fu Xi's eight trigrams into one single principle. Han Won Jin tries to explain the relation between He-tu and the formation of eight trigrams in terms of the relation between He-Tu and the circular diagram, and his attempt is widely supported by his colleagues. This theory runs counter to traditional model of explaining truth. My conjecture is that such academic trend is further developed by the defenders of Practical Learning such as Hong Dae Yong(洪大容), who vigorously reject traditional system of truth and science, and that it partly explains why the study of Yi Xue Qi Meng ceases in the nineteenth century.

Estimation of Fractional Urban Tree Canopy Cover through Machine Learning Using Optical Satellite Images (기계학습을 이용한 광학 위성 영상 기반의 도시 내 수목 피복률 추정)

  • Sejeong Bae ;Bokyung Son ;Taejun Sung ;Yeonsu Lee ;Jungho Im ;Yoojin Kang
    • Korean Journal of Remote Sensing
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    • v.39 no.5_3
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    • pp.1009-1029
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    • 2023
  • Urban trees play a vital role in urban ecosystems,significantly reducing impervious surfaces and impacting carbon cycling within the city. Although previous research has demonstrated the efficacy of employing artificial intelligence in conjunction with airborne light detection and ranging (LiDAR) data to generate urban tree information, the availability and cost constraints associated with LiDAR data pose limitations. Consequently, this study employed freely accessible, high-resolution multispectral satellite imagery (i.e., Sentinel-2 data) to estimate fractional tree canopy cover (FTC) within the urban confines of Suwon, South Korea, employing machine learning techniques. This study leveraged a median composite image derived from a time series of Sentinel-2 images. In order to account for the diverse land cover found in urban areas, the model incorporated three types of input variables: average (mean) and standard deviation (std) values within a 30-meter grid from 10 m resolution of optical indices from Sentinel-2, and fractional coverage for distinct land cover classes within 30 m grids from the existing level 3 land cover map. Four schemes with different combinations of input variables were compared. Notably, when all three factors (i.e., mean, std, and fractional cover) were used to consider the variation of landcover in urban areas(Scheme 4, S4), the machine learning model exhibited improved performance compared to using only the mean of optical indices (Scheme 1). Of the various models proposed, the random forest (RF) model with S4 demonstrated the most remarkable performance, achieving R2 of 0.8196, and mean absolute error (MAE) of 0.0749, and a root mean squared error (RMSE) of 0.1022. The std variable exhibited the highest impact on model outputs within the heterogeneous land covers based on the variable importance analysis. This trained RF model with S4 was then applied to the entire Suwon region, consistently delivering robust results with an R2 of 0.8702, MAE of 0.0873, and RMSE of 0.1335. The FTC estimation method developed in this study is expected to offer advantages for application in various regions, providing fundamental data for a better understanding of carbon dynamics in urban ecosystems in the future.

Determination of Fire Severity and Deduction of Influence Factors Through Landsat-8 Satellite Image Analysis - A Case Study of Gangneung and Donghae Forest Fires - (Landsat-8 위성영상 분석을 통한 산불피해 심각도 판정 및 영향 인자 도출 - 강릉, 동해 산불을 사례로 -)

  • Soo-Dong Lee;Gyoung-Sik Park;Chung-Hyeon Oh;Bong-Gyo Cho;Byeong-Hyeok Yu
    • Korean Journal of Environment and Ecology
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    • v.38 no.3
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    • pp.277-292
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    • 2024
  • In order to manage large-scale forest fires concentrated in Gangwon-do and Gyeongsangbuk-do with severe topographical heterogeneity, a decision-making process through efficient and rapid damage assessment using satellite images is essential. Accordingly, this study targets a large-scale forest fire that ignited in Gangneung and the Donghae, Gangwon-do on March 5, 2022, and was extinguished around 19:00 on March 8, to estimate the fire severity using dNBR and derive environmental factors that affect the grade. As environmental factors, we quantified the regular vegetation index representing vegetation or fuel type, the forest index that classifies tree species, the regular moisture index representing moisture content, and DEM in relation to topography, and then analyzed the correlation with the fire severity. In terms of fire severity, the widest range was 'Unbured' at 52.4%, followed by low severity at 42.9%, medium-low severity at 4.3%, and medium-high severity at 0.4%. Environmental factors showed a negative correlation with dNDVI and dNDWI, and a positive correlation with slope. Regarding vegetation, the differences between coniferous, broad-leaved, and other groups in dNDVI, dNIWI, and slope, which were analyzed to affect the fire severity, were analyzed to be significant with p-value < 2.2e-16. In particular, the difference between coniferous and broad-leaved forests was clear, and it was confirmed that coniferous forest suffered more damage than broad-leaved forest due to the higher fire severity in the Gangwon-do region, including Pinus densiflora, which are dominant species, as well as P. koraiensis, P. rigida and P. thunbergii.

Assessment of Cerebral Hemodynamic Changes in Pediatric Patients with Moyamoya Disease Using Probabilistic Maps on Analysis of Basal/Acetazolamide Stress Brain Perfusion SPECT (소아 모야모야병에서 뇌확률지도를 이용한 수술전후 혈역학적 변화 분석)

  • Lee, Ho-Young;Lee, Jae-Sung;Kim, Seung-Ki;Wang, Kyu-Chang;Cho, Byung-Kyu;Chung, June-Key;Lee, Myung-Chul;Lee, Dong-Soo
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.3
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    • pp.192-200
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    • 2008
  • To evaluate the hemodynamic changes and the predictive factors of the clinical outcome in pediatric patients with moyamoya disease, we analyzed pre/post basal/acetazolamide stress brain perfusion SPECT with automated volume of interest (VOIs) method. Methods: Total fifty six (M:F = 33:24, age $6.7{\pm}3.2$ years) pediatric patients with moyamoya disease, who underwent basal/acetazolamide stress brain perfusion SPECT within 6 before and after revascularization surgery (encephalo-duro-arterio-synangiosis (EDAS) with frontal encephalo-galeo-synangiosis (EGS) and EDAS only followed on contralateral hemisphere), and followed-up more than 6 months after post-operative SPECT, were included. A mean follow-up period after post-operative SPECT was $33{\pm}21$ months. Each patient's SPECT image was spatially normalized to Korean template with the SPM2. For the regional count normalization, the count of pons was used as a reference region. The basal/acetazolamide-stressed cerebral blood flow (CBF), the cerebral vascular reserve index (CVRI), and the extent of area with significantly decreased basal/acetazolamide- stressed rCBF than age-matched normal control were evaluated on both medial frontal, frontal, parietal, occipital lobes, and whole brain in each patient's images. The post-operative clinical outcome was assigned as good, poor according to the presence of transient ischemic attacks and/or fixed neurological deficits by pediatric neurosurgeon. Results: In a paired t-test, basal/acetazolamide-stressed rCBF and the CVRI were significantly improved after revascularization (p<0.05). The significant difference in the pre-operative basal/acetazolamide-stressed rCBF and the CVRI between the hemispheres where EDAS with frontal EGS was performed and their contralateral counterparts where EDAS only was done disappeared after operation (p<0.05). In an independent student t-test, the pre-operative basal rCBF in the medial frontal gyrus, the post-operative CVRI in the frontal lobe and the parietal lobe of the hemispheres with EDAS and frontal EGS, the post-operative CVRI, and ${\Delta}CVRI$ showed a significant difference between patients with a good and poor clinical outcome (p<0.05). In a multivariate logistic regression analysis, the ${\Delta}CVRI$ and the post-operative CVRI of medial frontal gyrus on the hemispheres where EDAS with frontal EGS was performed were the significant predictive factors for the clinical outcome (p =0.002, p =0.015), Conclusion: With probabilistic map, we could objectively evaluate pre/post-operative hemodynamic changes of pediatric patients with moyamoya disease. Specifically the post-operative CVRI and the post-operative CVRI of medial frontal gyrus where EDAS with frontal EGS was done were the significant predictive factors for further clinical outcomes.

The Comparison of Quantitative Indices by Changing an Angle of LAO View in Multi-Gated Cardiac Blood Pool Scan (게이트 심장 혈액풀 스캔에서 좌전사위상 각도의 변화에 따른 정량적 지표 비교)

  • Yoon, Soon-Sang;Nam, Ki-Pyo;Ryu, Jae-Kwang;Kim, Seong-Hwan
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.1
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    • pp.57-61
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    • 2012
  • Purpose: The multi-gated cardiac blood pool scan is to evaluate the function of left ventricle (LV) and usefully observe a value of ejection fraction (EF) for a patient who is receiving chemotherapy. To calculate LVEF, we should adjust an angle of left anterior oblique (LAO) view to separate both ventricles. And by overlapped ventricles, it is possible to affect LVEF. The purpose of this study is to investigate and compare quantitative indices by changing an angle of LAO view. Materials and methods: We analyzed the 49 patients who were examined by multi-gated cardiac blood pool scan in department of nuclear medicine at Asan Medical Center from June to September 2011. Firstly, we acquired "Best septal" view. And then, we got images by addition and subtraction of angle for LAO view to anterior and lateral. We compared three LAO views for 20 people by 5 degrees and 39 people by 10 degrees. And we analyzed quantitative indices, EF, end diastole and end systole counts, by automated and manual region of interest (ROI) modes. Results: Firstly, we analyzed quantitative indices by automated ROI mode. In case of 5 degrees, the averages of EF are $61.0{\pm}7.5$, $62.1{\pm}7.1$, $60.9{\pm}6.7%$ ($p$=0.841) in LAO, LAO $-5^{\circ}$ and LAO $+5^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). In case of 10 degrees, the averages of EF are $62.4{\pm}9.5$, $62.3{\pm}10.8$, $61.6{\pm}.9.3%$ ($p$=0.938) in LAO, LAO $-10^{\circ}$ and LAO $+10^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). Secondly, we analyzed quantitative indices by manual ROI mode. In case of 5 degrees, the averages of EF are $62.8{\pm}7.1$, $63.6{\pm}7.5$, $62.7{\pm}7.3%$ ($p$=0.903) in LAO, LAO $-5^{\circ}$ and LAO $+5^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). In case of 10 degrees, the averages of EF are $65.5{\pm}9.0$, $66.3{\pm}8.7$, $63.5{\pm}.9.3%$ (p=0.473) in LAO, LAO $-10^{\circ}$ and LAO $+10^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). Conclusion: When an image is nearly "Best septal" view, the difference of LAO angle would not affect to change LVEF. Although there was no difference in quantitative analysis, deviations could happen when to interpret wall motion qualitatively by reading physicians.

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A Study of Influence of Filgrastim on PET/CT In Diffuse Large B cell Lymphoma (미만성 거대 B 세포 림프종 환자에서 Filgrastim 사용이 PET/CT 영상에 미치는 영향에 대한 고찰)

  • NamKoong, Hyuk;Park, Hoon-Hee;Ban, Yung-Gak;Kang, Sin-Chang;Kim, Sang-Kyoo;Lim, Han-Sang;Lee, Chang-Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.3
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    • pp.17-23
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    • 2009
  • Purpose: It has been known that PET/CT is very valuable in follow-up study of diffuse large B cell lymphoma (DLBCL). Generally, in DLBCL, radiotherapy and chemotherapy has been progressed, because the lesion hasn‘t been limited to one site. And, it has lead to the decrease of leukocyte like neutropenia, due to myelosuppression of chemotherapy. So, in that case, administration of Filgrastim (Granulocyte colony-stimulating factor; G-CSF) is universal. However, in short time after administration, PET/CT has limitation to offer accurate images, through the uptake of $^{18}F$-FDG is increased in the region that is activated bone marrow by hematopoietic growth. Therefore, the aim of this study is that PET/CT in a certain period of time after administration of Filgrastim is able to show normal degree of $^{18}F$-FDG uptake. Materials and Methods: 10 patients under follow-up study of diffuse large B cell lymphoma were examined in this study from January, 2007 to January, 2009 (Male: 4 persons; Female: 6 persons; The mean age: 53.8 years old; The mean weight: 57.3 Kg). Using PET/CT (Discovery STe; GE Healthcare, Milwaukee, WI, USA), whole body images were acquired in 1 hour after $^{18}F$-FDG injection. For image analysis, each ROI ($120\;mm^2$) was drawn on $C^6$ (the sixth C-spine), $L_4$ (the forth L-spine), liver, spleen, and lung, then SUV (Standard Uptake Value)s were measured. We compared with each uptake between in 1-day and 5~7 days after administration of Filgrastim at same patient, so confirmed significance about these by SPSS version 12. Results: In case of $C_6$, $L_4$, spleen, every SUV of 1 day later was remarkably higher than that of 5~7 days later, but liver and lung were similar. Also, the images acquired after 5~7 days distinct remarkably and show normal degree of $^{18}F$-FDG uptake, because uptake of bone was almost disappeared. Conclusions: In this study, each SUV was prominent difference as a period of time after Filgrastim’s administration. And Filgrastim makes concentrate uptake of $^{18}F$-FDG in bone, but, after 5~7 days, bone‘s uptake was greatly decreased. Therefore, we are able to infer a certain period of time that shows normal degree of uptake, by numerical value proven. Also, we consider that this study contribute to advanced study about the other agent like Pegfilgrastim, Lenograstim besides Filgrastim, afterwards.

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Evaluation of Multiple System Atrophy and Early Parkinson's Disease Using $^{123)I$-FP-CIT SPECT ($^{123)I$-FP-CIT SPECT를 이용한 다중계위축증 및 조기 파킨슨병에서의 평가)

  • Oh, So-Won;Kim, Yu-Kyeong;Lee, Byung-Chul;Kim, Bom-Sahn;Kim, Ji-Sun;Kim, Jong-Min;Kim, Sang-Eun
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.1
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    • pp.10-18
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    • 2009
  • Purpose: We investigated quantification of dopaminergic transporter (DAT) and serotonergic transporter (SERT) on $^{123}I$-FP-CIT SPECT for differentiating between multiple systemic atrophy (MSA) and idiopathic Parkinson's disease (IPD). Materials and Methods: N-fluoropropyl-$2{\beta}$-carbomethoxy-$3{\beta}$-4-[$^{123}I$]-iodophenylnortropane SPECT ($^{123}I$-FP-CIT SPECT) was performed in 8 patients with MSA (mean age: $64.0{\pm}4.5yrs$, m:f=6:2), 13 with early IPD (mean age: $65.5{\pm}5.3yrs$, m:f=9:4), and 12 healthy controls (mean age: $63.3{\pm}5.7yrs$, m:f=8:4). Standard regions of interests (ROls) of striatum to evaluate DAT, and hypothalamus and midbrain for SERT were drawn on standard template images and applied to each image taken 4 hours after radiotracer injection. Striatal specific binding for DAT and hypothalamic and midbrain specific binding for SERT were calculated using region/reference ratio based on the transient equilibrium method. Group differences were tested using ANOVA with the postHoc analysis. Results: DAT in the whole striatum and striatal subregions were significantly decreased in both patient groups with MSA and early IPD, compared with healthy control (p<0.05 in all). In early IPD, a significant increase in the uptake ratio in anterior and posterior putamen and a trend of increase in caudate to putamen ratio was observed. In MSA, the decrease of DAT was accompanied with no difference in the striatal uptake pattern compared with healthy controls. Regarding the brain regions where $^{123}I$-FP-CIT binding was predominant by SERT, MSA patients showed a decrease in the binding of $^{123}I$-FP-CIT in the pons compared with controls as well as early IPD patients (MSA: $0.22{\pm}0.1$ healthy controls: $0.33{\pm}0.19$, IPD: $0.29{\pm}0.19$), however, it did not reach the statistical significance. Conclusion: In this study, the differential patterns in the reduction of DAT in the striatum and the reduction of pontine $^{123}I$-FP-CIT binding predominant by SERT could be observed in MSA patients on $^{123}I$-FP-CIT SPECT. We suggest that the quantification of SERT as well as DAT using $^{123}I$-FP-CIT SPECT is helpful to differentiate parkinsonian disorders in early stage.

A Refined Method for Quantification of Myocardial Blood Flow using N-13 Ammonia and Dynamic PET (N-13 암모니아와 양전자방출단층촬영 동적영상을 이용하여 심근혈류량을 정량화하는 새로운 방법 개발에 관한 연구)

  • Kim, Joon-Young;Lee, Kyung-Han;Kim, Sang-Eun;Choe, Yearn-Seong;Ju, Hee-Kyung;Kim, Yong-Jin;Kim, Byung-Tae;Choi, Yong
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.1
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    • pp.73-82
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    • 1997
  • Regional myocardial blood flow (rMBF) can be noninvasively quantified using N-13 ammonia and dynamic positron emission tomography (PET). The quantitative accuracy of the rMBF values, however, is affected by the distortion of myocardial PET images caused by finite PET image resolution and cardiac motion. Although different methods have been developed to correct the distortion typically classified as partial volume effect and spillover, the methods are too complex to employ in a routine clinical environment. We have developed a refined method incorporating a geometric model of the volume representation of a region-of-interest (ROI) into the two-compartment N-13 ammonia model. In the refined model, partial volume effect and spillover are conveniently corrected by an additional parameter in the mathematical model. To examine the accuracy of this approach, studies were performed in 9 coronary artery disease patients. Dynamic transaxial images (16 frames) were acquired with a GE $Advance^{TM}$ PET scanner simultaneous with intravenous injection of 20 mCi N-13 ammonia. rMBF was examined at rest and during pharmacologically (dipyridamole) induced coronary hyperemia. Three sectorial myocardium (septum, anterior wall and lateral wall) and blood pool time-activity curves were generated using dynamic images from manually drawn ROIs. The accuracy of rMBF values estimated by the refined method was examined by comparing to the values estimated using the conventional two-compartment model without partial volume effect correction rMBF values obtained by the refined method linearly correlated with rMBF values obtained by the conventional method (108 myocardial segments, correlation coefficient (r)=0.88). Additionally, underestimated rMBF values by the conventional method due to partial volume effect were corrected by theoretically predicted amount in the refined method (slope(m)=1.57). Spillover fraction estimated by the two methods agreed well (r=1.00, m=0.98). In conclusion, accurate rMBF values can be efficiently quantified by the refined method incorporating myocardium geometric information into the two-compartment model using N-13 ammonia and PET.

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The Evaluation of SUV Variations According to the Errors of Entering Parameters in the PET-CT Examinations (PET/CT 검사에서 매개변수 입력오류에 따른 표준섭취계수 평가)

  • Kim, Jia;Hong, Gun Chul;Lee, Hyeok;Choi, Seong Wook
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.43-48
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    • 2014
  • Purpose: In the PET/CT images, The SUV (standardized uptake value) enables the quantitative assessment according to the biological changes of organs as the index of distinction whether lesion is malignant or not. Therefore, It is too important to enter parameters correctly that affect to the SUV. The purpose of this study is to evaluate an allowable error range of SUV as measuring the difference of results according to input errors of Activity, Weight, uptake Time among the parameters. Materials and Methods: Three inserts, Hot, Teflon and Air, were situated in the 1994 NEMA Phantom. Phantom was filled with 27.3 MBq/mL of 18F-FDG. The ratio of hotspot area activity to background area activity was regulated as 4:1. After scanning, Image was re-reconstructed after incurring input errors in Activity, Weight, uptake Time parameters as ${\pm}5%$, 10%, 15%, 30%, 50% from original data. ROIs (region of interests) were set one in the each insert areas and four in the background areas. $SUV_{mean}$ and percentage differences were calculated and compared in each areas. Results: $SUV_{mean}$ of Hot. Teflon, Air and BKG (Background) areas of original images were 4.5, 0.02. 0.1 and 1.0. The min and max value of $SUV_{mean}$ according to change of Activity error were 3.0 and 9.0 in Hot, 0.01 and 0.04 in Teflon, 0.1 and 0.3 in Air, 0.6 and 2.0 in BKG areas. And percentage differences were equally from -33% to 100%. In case of Weight error showed $SUV_{mean}$ as 2.2 and 6.7 in Hot, 0.01 and 0.03 in Tefron, 0.09 and 0.28 in Air, 0.5 and 1.5 in BKG areas. And percentage differences were equally from -50% to 50% except Teflon area's percentage deference that was from -50% to 52%. In case of uptake Time error showed $SUV_{mean}$ as 3.8 and 5.3 in Hot, 0.01 and 0.02 in Teflon, 0.1 and 0.2 in Air, 0.8 and 1.2 in BKG areas. And percentage differences were equally from 17% to -14% in Hot and BKG areas. Teflon area's percentage difference was from -50% to 52% and Air area's one was from -12% to 20%. Conclusion: As shown in the results, It was applied within ${\pm}5%$ of Activity and Weight errors if the allowable error range was configured within 5%. So, The calibration of dose calibrator and weighing machine has to conduct within ${\pm}5%$ error range because they can affect to Activity and Weight rates. In case of Time error, it showed separate error ranges according to the type of inserts. It showed within 5% error when Hot and BKG areas error were within ${\pm}15%$. So we have to consider each time errors if we use more than two clocks included scanner's one during the examinations.

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