• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.99-103
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• 2011

Purpose: Head movement during brain perfusion SPECT (Diamox) scan is a one of important issues which decreases image quality. It also causes repeated scans. This study was designed to evaluate variable factors causing scan failures. Materials and Methods: 676 patients (359 men, 317 women, age average $54.5{\pm}18.4$) for brain perfusion SPECT (Diamox) scan from March, 2010 to Feb. 2011 were used as a subject. Age data and the kind of disease(Moyamoya disease (MMD), None moyamoya disease (NMMD), Cerebral infarction (CI)), test performance outcome (success,failure) were collected. The head movement factors(gender, disease, age, head fixation device) were evaluated by chi-square test and logistic regression analysis Results: The result showed that men had higher scan failure rate than women. Seniors in seventies(men 3.4%, women 1.5%) showed the most highest failure rate. Using head fixation device increased scan success rate up to 94.4~97.7%. The scan success rate is dependent upon gender, head fixation device by chi-square test(${\chi}^2$=3.8 (df=1, p<0.05), ${\chi}^2$=10.4 (df=1, p<0.001)) Gender, disease(CI), head fixation device showed very effective result in logistic regression analysis.(Wald=3.3 (p<0.07), Wald=3.7 (p<0.05), Wald=9.3 (p<0.05) Conclusion: It is demonstrated that gender, disease, using head fixation device is statistically very useful factors. Especially, head fixation device is a main key minimizing repeated scan.

• The Korean Journal of Nuclear Medicine
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• v.34 no.3
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• pp.222-227
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• 2000

Purpose: We compared estimates of ejection fraction (EF) determined by gated Tl-201 perfusion SPECT (g-Tl-SPECT) with those by gated blood pool (GBP) scan. Materials and Methods: Eighteen subjects underwent g-Tl-SPECT and GBP scan. After reconstruction of g-Tl-SPECT, we measured EF with Cedars software. The comparison of the EF with g-Tl-SPECT and GBP scan was assessed by correlation analysis and Bland Altman plot. Results: The estimates of EF were significantly different (p<0.05) with g-Tl-SPECT ($40%{\pm}14%$) and GBP scan ($43%{\pm}14%$). There was an excellent correlation of EF between g-Tl-SPECT and GBP scan (r=0.94, p<0.001). The mean difference of EF between GBP scan and g-Tl-SPECT was +3.2% Ninety-five percent limits of agreement were ${\pm}9.8%$. EF between g-Tl-SPECT and GBP scan were in poor agreement. Conclusion: The estimates of EF by g-Tl-SPECT was well correlated with those by GBP scan. However, EF of g-Tl-SPECT doesn't agree with EF of GBP scan. EF of g-Tl-SPECT can't be used interchangeably with EF of GBP scan.

• Investigative Magnetic Resonance Imaging
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• v.15 no.2
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• pp.91-101
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• 2011

Perfusion magnetic resonance imaging (pMRI) is a special technique for evaluation of blood flow. Exogenous pMRI methods which are dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) use an intravenous bolus injection of paramagnetic contrast agent. In contrast, an endogenous pMRM method which is arterial spin labeling (ASL) use diffusible blood in body. In order to scan pMRI in human, technical optimizations are very important according to disease conditions. For examples, DSC is popularly used in patients with acute stroke due to its short scan time, while DSC or DCE provides the various perfusion indices for patients with tumor. ASL is useful for children, women who are expected to be pregnant, and in patients with kidney diseases which are problematic in nephrogenic systemic fibrosis (NSF). Perfusion MRI does not require any injection of radioisotopes. We expect that demand for perfusion MRI will be higher in evaluating drug efficacy and other treatment effects.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.353-358
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• 2014

This study was conducted to analyze the patient's exposed dose targeting the patients who had acute ischemic stroke symptoms and CT brain perfusion scan, by comparing fixed time technique and bolus tracking technique which was provided by the manufacturer and to identify the Time graph to implement the usability of contrast medium's tracking technique the best contrast enhancement intervals. $CTDI_{VOL}$ of PCT in patient appeared to be 431.72mGy in fixed scan delay protocol, whereas 323.61mGy in Bolus tracking technique. The value of DLP appeared to be $1243.47mGy{\cdot}cm$ in fixed scan delay protocol, whereas $932mGy{\cdot}cm$ in Bolus tracking technique. Time graph appeared to be various in fixed scan delay protocol, whereas the optimal time graph could be obtained in Bolus tracking. The exposure dose could be reduced by 25% applying Bolus tracking technique when taking brain perfusion CT scan.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.67-72
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• 2010

Purpose: In Asan Medical Center we perform myocardial perfusion SPECT to evaluate cardiac event risk level for non-cardiac surgery patients. In case of patients with cancer, we check tumor metastasis using whole body bone scan and whole body PET scan and then perform myocardial perfusion SPECT to reduce unnecessary exam. In case of short term in patients, we perform $^{201}Tl$ myocardial perfusion SPECT after whole body bone scan a minimum 16 hours in order to reduce hospitalization period but it is still the actual condition in which the evaluation about the affect of the crosstalk contamination due to the each other dissimilar isotope administration doesn't properly realize. So in our experiments, we try to evaluate crosstalk contamination influence on $^{201}Tl$ myocardial perfusion SPECT using anthropomorphic torso phantom and patient's data. Materials and Methods: From 2009 August to September, we analyzed 87 patients with $^{201}Tl$ myocardial perfusion SPECT. According to $^{201}Tl$ myocardial perfusion SPECT yesterday whole body bone scan possibility of carrying out, a patient was classified. The image data are obtained by using the dual energy window in $^{201}Tl$ myocardial perfusion SPECT. We analyzed $^{201}Tl$ and $^{99m}Tc$ counts ratio in each patients groups obtained image data. We utilized anthropomorphic torso phantom in our experiment and administrated $^{201}Tl$ 14.8 MBq (0.4 mCi) at myocardium and $^{99m}Tc$ 44.4 MBq (1.2 mCi) at extracardiac region. We obtained image by $^{201}Tl$ myocardial perfusion SPECT without gate method application and analyzed spatial resolution using Xeleris ver 2.0551. Results: In case of $^{201}Tl$ window and the counts rate comparison result yesterday whole body bone scan of being counted in $^{99m}Tc$ window, the difference in which a rate to 24 hours exponential-functionally notes in 1:0.114 with Ventri (GE Healthcare, Wisconsin, USA), 1:0.249 after the bone tracer injection in 12 hours in 1:0.411 with 1:0.79 with Infinia (GE healthcare, Wisconsin, USA) according to a reduction a time-out was shown (Ventri p=0.001, Infinia p=0.001). Moreover, the rate of the case in which it doesn't perform the whole body bone scan showed up as the average 1:$0.067{\pm}0.6$ of Ventri, and 1:$0.063{\pm}0.7$ of Infinia. According to the phantom after experiment spatial resolution measurement result, and an addition or no and time-out of $^{99m}Tc$ administrated, it doesn't note any change of FWHM (p=0.134). Conclusion: Through the experiments using anthropomorphic torso phantom and patients data, we found that $^{201}Tl$ myocardium perfusion SPECT image later carried out after the bone tracer injection with 16 hours this confirmed that it doesn't receive notable influence in spatial resolution by $^{99m}Tc$. But this investigation is only aimed to image quality, so it needs more investigation in patient's radiation dose and exam accuracy and precision. The exact guideline presentation about the exam interval should be made of the validation test which is exact and in which it is standardized about the affect of the crosstalk contamination according to the isotope use in which it is different later on.

• Journal of Chest Surgery
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• v.28 no.12
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• pp.1096-1106
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• 1995

We experienced 7 cases of left single lung transplantation in 14 mongrel dogs and analyzed graft lung function by hemodynamics, blood gas analysis, chest X-ray, biopsy and perfusion lung scan. We performed right pulmonary artery cuff[PA cuff for analysis of graft lung function in 3 cases. The donor lungs were flushed with modified Euro-Collins solution[n=3 or low potassium dextran glucose solution[n=4 and preserved for 4 to 5 hours[n=4 or 24 hours[n=3 at 10o C and implanted to the dogs with similar weight . Assessment of left graft lung was done by occluding the right pulmonary artery for 10 minutes using PA cuff. Assessment for graft lung function was done immediately after an operation and after 3 days, 7days and 3 weeks postoperatively. Four dogs survived for 3days, 7days[2 cases and 3 weeks respectively. Other three dogs expired within 3 hours of reperfusion. Immediate perfusion scans of left lung in four survived dogs after reperfusion were 42.1%, 36% , 11% and 5.9% respectively, and another dog with 4.8% perfusion to left lung was dead due to left atrial thrombi after 3 hours reperfusion. In one case among three acute rejections follow-up perfusion scan was done on 3rd and 11th postoperative day and the result decreased from 36% perfusion immediate postoperatively to 21% and 15% respectively. Three expired dogs postoperatively couldn`t tolerate occlusion of right pulmonary artery with above 40 mmHg of mean pulmonary artery pressure. On the other hand, three survival dogs postoperatively tolerated occlusion of right pulmonay artery with less than 30 mmHg of mean pulmonary artery pressure. and one dog couldn`t tolerate same procedure immediate postopertively but in 2 hours reperfusion later tolerated with 29 mmHg of mean pulmonary artery pressure.In conclusion we couldn`t compare the effect of two flushing solutions but low potassium dextran glucose solution showed relatively safe preservation effect in cases with preservation of more than 20 hours. Also canine left single lung transplantation model with PA cuff indicated useful method for the assessment of graft lung function with effect of lung preservation.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.569-572
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• 1996

A sixty nine-year-old mate patient was admitted with a chief complaint of exertional dyspnea. Lung perfusion scan revealed total perfusion defect of the of left lung and CT anglography showed the ab- rupt cutoff left pulmonary artery. He denied of trauma history, previous lower leg symptom and sign, or any embolic history. With the impression of chronic pulmonary thromboembolism of unknown etiology, operation was done under the cardiopulmonary bypass through a median sternotomy. After main pulmonary artery clamping and pulmonary arteriotomy, thromboembolectomy was done. Postoperative lung perfusion scan and CT angiography showed near normal left pulmonary blood flow. The patient was discharged on the postoperative 9th day without any postoperative complication.

• The Korean Journal of Nuclear Medicine
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• v.30 no.4
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• pp.502-506
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• 1996

Tc-99m myocardial perfusion agents such as Tc-99m sestamibi or Tc-99m tetrofosmin has advantages over T1-201 for myocardial perfusion scan fuck as low attenuation and easy availability. However, Tc-99m agents do not redistribute so they need to be given T times, namely after stress and at rest. To evaluate whether rest image is needed in patients showing normal stress image, 43 patients who underwent both myocardial perfusion scan and coronary angiography and showed normal stress images were evaluated. Findings of rest images of them were evaluated whether they change the diagnosis or treatment plans. Among 43 patients who showed normal stress myocardial perfusion imaging, 31 (72.1%) showed no additional informations. However, among 5 patients with vasospastic angina 4 (80%) showed abnormal rest images in spite of normal stress images. So, when vasospastic angina is suspected clinically, rest image could be helpful in identifying patients with coronary vasospasm. In conclusion, rest myocardial perfusion images were not helpful in 72.1 % of patients with angina when stress images were normal. In only exception was those with vasospastic angina.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.163-169
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• 1986

Intrapulmonary shunt was measured by $^{99m}Tc$-MAA perfusion tung scan. The study was included 76 patients. Significant amount of intrapulmonary shunt was observed in the pulmonary disease patients and liver disease patients. The shunt amount was correlated well with $PaO_2$ and $AaDO_2$ level. Further study is needed to search the various factors affecting the amount of intrapulmonary shunt.

• 대한핵의학회:학술대회논문집
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• 1985.05a
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• pp.169.2-170
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• 1985