• 대한핵의학회:학술대회논문집
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• 1990.04a
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• pp.211.2-212
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• 1990

• Journal of radiological science and technology
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• v.36 no.4
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• pp.319-326
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• 2013

The purpose of this study is to evaluate usefulness of Hybrid image and Inverse image about detection of tumor shadow in chest radiography using ROC analysis. Original images of 60 cases are selected from Standards digital image date base issued by the Japanese Society of Radiological Technology. Through computer language of C, Inverse images of 60 cases and Hybrid image of 30 cases are made. The continues reading experiment was conducted. In the case of inverse image were observed by 5 radiographer and 2 radiologist. In the case of In case of Hybrid image were observed by 3 student radiographer and 2 experienced radiographer. ROC curve are constructed using ROCKIT Program made by Metz. In Inverse image, a Az of average ROC curve was increases from 0.742 of original image to 0.775 of inverse image. In normal cases, the effect of the detrimental is same to that of the beneficial, however In abnormal cases, the beneficial effect is greater than detrimental effect. However in Hybrid image, a Az of average ROC curve was decreases from 0.5253 of original image to 0.4868 of Hybrid image. In Normal cases, the effect of the detrimental is greater than that of the Beneficial, however In abnormal cases, the Beneficial effect is greater than detrimental effect. The inverse image can be more positively considered for the detecting of tumor than the hybrid image.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.57-62
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• 2009

Purpose: Brain SPECT study is more sensitive to motion than other studies. Especially, when applying 1-day subtraction method for Diamox SPECT, it needs shorter study time in order to prevent reexamination. We were required to have new study condition and analysing method on dual detector system because triple head camera in Seoul National University Hospital is to be disposed. So we have tried to increase image quality and make the dual and triple head to have equivalent study time by using a new analysing program. Materials and Methods: Using IEC phantom, we estimated contrast, SNR and FWHM. In Hoffman 3D brain phantom which is similar with real brain, we were on the supposition that 5% of injected doses were distributed in brain tissue. To compare with existing FBP method, we used fan-beam collimator. And we applied 15 sec, 25 sec/frame for each SEPCT studies using LEHR and LEUHR. We used OSEM2D and Onco-flash3D reconstruction method and compared reconstruction methods between applied Gaussian post-filtering 5mm and not applied as well. Attenuation correction was applied by manual method. And we did Brain SPECT to patient injected 15 mCi of $^{99m}Tc$-HMPAO according to results of Phantom study. Lastly, technologist, MD, PhD estimated the results. Results: The study shows that reconstruction method by Flash3D is better than exiting FBP and OSEM2D when studied using IEC phantom. Flowing by estimation, when using Flash3D, both of 15 sec and 25 sec are needed postfiltering 5 mm. And 8 times are proper for subset 8 iteration in Flash3D. OSEM2D needs post-filtering. And it is proper that subset 4, iteration 8 times for 15sec and subset 8, iteration 12 times for 25sec. The study regarding to injected doses for a patient and study time, combination of input parameter-15 sec/frame, LEHR collimator, analysing program-Flash3D, subset 8, iteration 8times and Gaussian post-filtering 5mm is the most appropriate. On the other hands, it was not appropriate to apply LEUHR collimator to 1-day subtraction method of Diamox study because of lower sensitivity. Conclusions: We could prove that there was also an advantage of short study time effectiveness in Dual camera same as Triple gamma camera and get great result of alternation from existing fan-beam collimator to parallel collimator. In addition, resolution and contrast of new method was better than FBP method. And it could improve sensitivity and accuracy of image because lesser subjectivity was input than Metz filter of FBP. We expect better image quality and shorter study time of Brain SPECT on Dual detector system.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.54-62
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• 1996

Background: $^{99m}Tc$ MIBI(Methoxyisobutylisonitrile complex), a member of the isonitrile class of coordination compounds, is a lipophilic cation presently under investigation for clinical use as myocardial perfusion imaging agent and is widely used to detect myocardial infarction. Preliminary reports indicate that $T_1$-201 accumulate in human neoplasm and several authors reported $^{99m}Tc$ MIBI may also localized in primary malignant tumor and metastatic deposits from lung cancer. We evaluated the uptake of $^{99m}Tc$ MIBI in lung cancer and localization of mediastinal and other site metastasis, and compared the benign lesion of the lung. Method: Thirty four patients of lung cancer and ten patients of benign lung lesion were studied with chest CT and $^{99m}Tc$ MIBI Lung SPECT. $^{99m}Tc$ MIBI uptake ratio was assessed by TR/NL(Lung lesion/ Normal area), HT/NL (Heart/Normal area) and HT/TR(Heart/Lung lesion). Results: 1) All lung cancer patients showed increased uptakes of $^{99m}Tc$ MIBI in malignant lung lesion and Tc-99m MIBI uptake was also increased in mediastinal and lymph node metastasis except two cases. 2) There was significant different ratio of TR/NL between malignant and benign lesion, $3.79{\pm}1.82$ and $1.67{\pm}0.63$ on planar images, respectively(p<0.001). 3) There was no significant difference of $^{99m}Tc$ MIBI uptake ratio between squamous cell carcinoma, small cell carcinoma and adeno carcinoma($3.64{\pm}1.66$, $3.57{\pm}0.72$, $4.31{\pm}2.28$ respectively). Conclusion: $^{99m}Tc$ MIBI lung SPECT was useful in the localization of tumor and mediastinal or other site metastatic lesion in lung cancer and also in the differential diagnosis between benign and malignant lesion.