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Analyze for the Quality Control of General X-ray Systems in Capital region (수도권지역 일반촬영 장비의 정도관리 분석)

  • Kang, Byung-Sam;Lee, Kang-Min;Shim, Woo-Yong;Park, Soon-Chul;Choi, Hak-Dong;Cho, Yong-Kwon
    • Journal of radiological science and technology
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    • v.35 no.2
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    • pp.93-102
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    • 2012
  • Thanks to the rapid increase of the interest in the quality control of the General X-ray systems, this research proposes the direction of the quality control through comparing and inspecting the actual condition of the respective quality control in the Clinic, the educational institution and the hospital. The subjects of the investigation are diagnostic radiation equipment's in the clinic, the educational institution and the hospital around the capital. A test of kVp, mR/mAs out put test and reproducibility of the exposure dose, half value layer, an accordance between the light field and the beam alignment test, and lastly reproducibility of the exposure time. Then the mean difference of the percentage, the CV (Coefficient of Variation, CV) and the attenuated curve which are respectively resulted from the above tests are computed. After that we have evaluated the values according to the regulations on the Diagnostic Radiation Equipment Safety Administration regulations. In the case of the clinic and the educational institution, there were 22 general X-ray devices. And 18.2% of the kVp test, 13.6% of the reproducibility of exposure dose test, 9.1% of the mR/mAs out put test, and 13.6% of the HVL (Half Value Layer) test appeared to be improper. In the case of the hospital, however, there were 28 devices. And 7.1% of the reproducibility of exposure dose, 7.1% of the difference in the light field/ beam alignment, and 7.1% of the reproducibility of the exposure time appeared to be improper. According to the investigation, the hospital's quality control condition is better than the condition in the clinic and the educational institution. The quality control condition of the general X-ray devices in the clinic is unsatisfactory compared to the hospital. Thus, it is considered that realizing the importance of the quality control is necessary.

A COG Variable Analysis of Air-rolling-breakfall in Judo (유도 공중회전낙법의 COG변인 분석)

  • Kim, Eui-Hwan;Chung, Chae-Wook;Kim, Sung-Sup
    • Korean Journal of Applied Biomechanics
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    • v.15 no.3
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    • pp.117-132
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    • 2005
  • It was to study a following research of "A Kinematic Analysis of Air-rolling-breakfall in Judo". The purpose of this study was to analyze the Center of Gravity(COG) variables when performing Air-rolling-breakfall motion, while passing forward over(PFO) to the vertical-hurdles(2m height, take off board 1m height) in judo. Subjects were four males of Y. University squad, who were trainees of the demonstration exhibition team, representatives of national level judoists and were filmed by four 5-VHS 16mm video cameras(60field/sec.) through the three dimensional film analysis methods.COG variable were anterior-posterior directional COG and linear velocity of COG, vertical directional COG and linear velocity of COG. The data collections of this study were digitized by KWON3D program computed The data were standardized using cubic spline interpolation based by calculating the mean values and the standard deviation calculated for each variables. When performing the Air-rolling-breakfall, from the data analysis and discussions, the conclusions were as follows : 1. Anterior-posterior directional COG(APD-COG) when performing Air-rolling-breakfall motion, while PFO over to the vertical-hurdles(2m height) in judo. The range of APD-COG by forward was $0.31{\sim}0.41m$ in take-off position(event 1), $1.20{\sim}1.33m$ in the air-top position(event 2), $2.12{\sim}2.30m$ in the touch-down position(event 3), gradually and $2.14{\sim}2.32m$ in safety breakfall position(event 4), respectively. 2 The linear velocity of APD-COG was $1.03{\sim}2.14m/sec$. in take-off position(event 1), $1.97{\sim}2.22m/sec$. gradually in the air-top position(event 2), $1.05{\sim}1.32m/sec$. in the touch-down position (event 3), gradual decrease and $0.91{\sim}1.23m/sec$. in the safety breakfall position(event 4), respectively. 3. The vertical directional COG(VD-COG) when performing Air-rolling-breakfall motion, while PFO to the vertical-hurdles(2m height) in judo. The range of VD-COG toward upward from mat was $1.35{\sim}1.46m$ in take-off position(event 1), the highest $2.07{\sim}2.23m$ in the air-top position(event 2), and after rapid decrease $0.3{\sim}0.58m$ in the touch-down position(event 3), gradual decrease $0.22{\sim}0.50m$ in safety breakfall position(event 4), respectively. 4. The linear velocity of VlJ.COG was $1.60{\sim}1.87m/sec$. in take-off position(event 1), $0.03{\sim}0.08m/sec$. gradually in the air-top position(event 2), $-4.37{\sim}\;-4.76m/sec$. gradual decrease in the touch-down position(event 3), gradual decrease and -4.40${\sim}\;-4.77m/sec$. in safety breakfall position(event 4), respectively. When performing Air-rolling-breakfall showed parabolic movement from take-off position to air-top position, and after showed vertical fall movement from air-top position to safety breakfall. In conclusion, Ukemi(breakfall) is safety fall method Therefore, actions need for performing safety fall movement, that decrease and minimize shock and impact during Air-rolling-breakfall from take-off board action to air-top position must be maximize of angular momentum, and after must be minimize in touch-down position and safety breakfall position.

Clinical Research for Otitis Media with Effusion Using Tympanometry (Tympanometry를 이용한 삼출성 중이염의 임상적 관찰에 대한 연구)

  • Park, Owe-Suk;Yoon, Hui-Sung;Kim, Hee-Jeong;Kim, Keoo-Seok;Kim, Yoon-Bum
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.18 no.3
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    • pp.84-94
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    • 2005
  • Objective: In order to help clinical approach on OME patient in progress observation and decision on improvement by clinical research results using tympanometry. Methods: Data was collected from 163 ears of 96 patients who were treated in Dept. of Oriental Medical Ophthalmology & Otolaryngology & Dermatology, Kyung-Hee Medical Center from 2001-2-12 to 2005-4-29 for Otitis Media with Effusion(OME). Tympanometry was applied to all patients and the test result was used to evaluate progress and improvement. F/U cases below 3 times were excluded. Results & conclusion: 1. Age and sex distribution was as follows: Mean Age 5.5years old(Standard deviation: 2.1), age distribution 2-61years old, below 10years old 151cases(92.6%) and above 10years old 12cases(7.4%). Male and female ratio was 1.81:1. 2. There were 67people(69.8%) with bilateral affected ear. Unilateral was 29people(30.2%). Affected ear distribution according to sex came out similarly. 3. Affected period distribution was as follows: over 12weeks 71cases(43.6%), under 12weeks 92cases(56.4%). Out of under 12weeks cases, 2-4weeks was 34cases(20.9%), 0-1weeks and 5-8weeks 20cases(12.3%), 9-12weeks 18cases(11.0%). There was evident difference about affected period between male and female. 4. All patients who served previous Tx in medical clinic(118 cases) took antibiotics. Only 6cases took tube insertion. The period of Taking antibiotics was as fellows: over 6weeks 42cases(35.6%), under 5weeks 37cases(31.4%). unknown 25cases(21.2%), jntermittent 14cases(11.9%). 5. In Period of Tx distribution, 5-6weeks showed 40cases(24.5%) which was highest number. In Improved cases(85cases), 3-4weeks and 5-6weeks each 22cases(25.9%) which was highest number. 1-2weeks 3cases(3.5%), 7-8weeks 12cases(14.1%), 9-10weeks 9cases(10.6%), 11-12weeks 10cases(11.8%), over 12weeks 7cases(8.2%). 6. The cases which have gastrointestinal Sx were 71cases(43.6%), the others 92cases(56.4%). Details of gastrointestinal Sx were as follows: Sx associated with appetite 47cases(47.5%), constipation 15cases(15.2%), abdominal pain and diarrhea 14cases(14.1%), frequent vomitting Teases(7.1%), etc 4cases(4.0%). 7. The cases which have accompanying disease were 116case(71.2%), the other 47cases(28.8%). Details a accompanying disease were as follows: sinusitis 57cases(35%), rhinitis 55cases(3.7%), allergic rhinitis 20cases(12.3%), atopic dermatitis 19cases(1.7%), urticaria 4cases(2.5%), asthma 3cases(1.8%), nasal polyp and conjunctivitis 2cases(1.2%) each, laryngitis 1case(0.6%).

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Comparison of Pulsatile and Non-Pulsatile Extracorporeal Circulation on the Pattern of Coronary Artery Blood Flow (체외순환에서 박동 혈류와 비박동 혈류가 관상동맥 혈류양상에 미치는 영향에 대한 비교)

  • Son Ho Sung;Fang Yong Hu;Hwang Znuke;Min Byoung Ju;Cho Jong Ho;Park Sung Min;Lee Sung Ho;Kim Kwang Taik;Sun Kyung
    • Journal of Chest Surgery
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    • v.38 no.2 s.247
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    • pp.101-109
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    • 2005
  • Background: In sudden cardiac arrest, the effective maintenance of coronary artery blood flow is of paramount importance for myocardial preservation as well as cardiac recovery and patient survival. The purpose of this study was to directly compare the effects of pulsatile and non-pulsatile circulation to coronary artery flow and myocardial preservation in cardiac arrest condition. Material and Method: A cardiopulmonary bypass circuit was constructed in a ventricular fibrillation model using fourteen Yorkshire swine weighing $25\~35$ kg each. The animals were randomly assigned to group I (n=7, non-pulsatile centrifugal pump) or group II (n=7, pulsatile T-PLS pump). Extra-corporeal circulation was maintained for two hours at a pump flow of 2 L/min. The left anterior descending coronary artery flow was measured with an ultrasonic coronary artery flow measurement system at baseline (before bypass) and at every 20 minutes after bypass. Serologic parameters were collected simultaneously at baseline, 1 hour, and 2 hours after bypass in the coronary sinus venous blood. The Mann-Whitney U test of STATISTICA 6.0 was used to determine intergroup significances using a p value of < 0.05. Result: The resistance index of the coronary artery was lower in group II and the difference was significant at 40 min, 80 min, 100 min and 120 min (p < 0.05). The mean velocity of the coronary artery was higher in group II throughout the study, and the difference was significant from 20 min after starting the pump (p < 0.05). The coronary artery blood flow was higher in group II throughout the study, and the difference was significant from 40 min to 120 min (p < 0.05) except at 80 min. Serologic parameters showed no differences between the groups at 1 hour and 2 hours after bypass in the coronary sinus blood. Conclusion: In cardiac arrest condition, pulsatile extracorporeal circulation provides more blood flow, higher flow velocity and less resistance to coronary artery than non-pulsatile circulation.

Analysis of Surgical Risk Factors in Pulmonary (폐국균종의 수술위험인자 분석)

  • 김용희;이은상;박승일;김동관;김현조;정종필;손광현
    • Journal of Chest Surgery
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    • v.32 no.3
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    • pp.281-286
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    • 1999
  • Background: The purpose of this study is to analyze the types of complications, the incidences of complications, and preoperative and postoperative risk factors affecting the incidence of the complication. Material and Method: Between August 1990 and August 1997 in Asan Medical Center, 42 patients(24 men and 18 women) underwent surgical resection for pulmonary aspergilloma. The mean age was 46.6${\pm}$11.5 years(range 29 to 69 years). Hemoptysis(90%) was the most common presentation. Pulmonary tuberculosis was the most common predisposing cause(81%). The associated diseases were bronchiectasis(n=11), active puolmonary tuberculosis(n=9), diabetes mellitus(n=8), lung carcinoid(n=1), and acute myeloblastic leukemia(n=1). Lobectomy was done in 32 cases(76%), segmentectomy or wedge resection in 4, pneumonectomy in 2, and lobectomy combined with segmentectomy in 4. Result: Operative mortality was 2%. The most common postoperative complication was persistent air leakage(n=6). The variables such as age, sex, pulmonary function test, amount and duration of hemoptysis, associated diseases(diabetes mellitus, active pulmonary tuberculosis), mode of preoperative management(steroid, antifungal agent, bronchial arterial embolization), and modes of operative procedures were statistically insignificant. The radiologic extent of infiltration to normal lung parenchyme was statistically significant(p=0.04). Conclusion: We conclude that the extent of the infiltration to normal lung parenchyme in preoperative radiologic studies should be carefully evaluated to reduce the postoperative complications in surgery for pulmonary aspergilloma.

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Cause-specific Analysis of Risk Factors in Completely Resected Pathologic Stage Ia Non-small Cell Lung Cancer (병리학적 병기 Ia기 비소세포폐암 환자에서 완전절제술 후 사망의 원인에 따른 위험인자 분석)

  • Park, Seong-Yong;Park, In-Kyu;Byun, Chun-Sung;Lee, Chang-Young;Bae, Mi-Kyung;Kim, Dae-Joon;Chung, Kyung-Young
    • Journal of Chest Surgery
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    • v.42 no.6
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    • pp.725-731
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    • 2009
  • Background: Lobectomy and more extended anatomic resection are regarded as standard treatment for stage Ia non-small cell lung cancer, but approximately 15~40% of patients suffer from treatment failures such as cancer recurrence or death. The authors analyzed types and causes of treatment failures in surgically treated cases of stage Ia non small cell lung cancer. Material and Method: We retrospectively reviewed the medical records of 156 patients who had undergone complete resection for stage Ia NSCLC between Jan 1992 and Aug 2005. Patients were divided into two different treatment failure groups: cancer-related deaths and non-cancer-related deaths. Risk factors were analyzed in each group by the Kaplan-Meyer survival method and the Cox proportional hazard model. Result: Among the 156 patients, 93 were males; the mean age was 61. The median follow-up period was 33.8 months. The 5 year survival rate was 87.6%. Microscopic lympho-vascular permeation was reported in 10 patients. Recurrence was reported in 19 patients and 12 patients died due to recurrent lung cancer. Noncancer related deaths occurred in 16 patients. Risk factors for cancer recurrence and cancer related death were microscopic lympho-vascular permeation (HR=6.81, p=0.007, HR=7.81, p<0.001); for non-cancer related death, risk factors were pneumonectomy (HR=25.92, p=0.001) and postoperative cardiopulmonary complications (HR=29.67, p=0.002). Conclusion: After complete resection of stage Ia non small cell lung cancer patients, mortality includes not only cancer related deaths but also cancer unrelated deaths. Adjuvant chemotherapy is advised for patients who show microscopic lympho-vascular permeation, which is a risk factor for recurrence and for cancer related death. Patients who had pneumonectomy or who suffered from cardiac or respiratory complications need meticulous care in order to reduce comorbidity-induced death.

Adenocarcinoma of the Uterine Cervix (자궁경부선암의 방사선 치료)

  • Chung Eun Ji;Shin Hyun Soo;Lee Hyung Sik;Kim Gwi Eon;Loh John Juhn-Kyu;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.9 no.2
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    • pp.277-284
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    • 1991
  • Survival data, prognostic factors, and patterns of failure were retrospectively analyzed for a total of 76 patients with adenocarcinoma of the uterine cervix treated between January 1981 and December 1987, which represents $4.1\%$ of all primary cervical carcinomas treated, at Department of Radiation Oncology, Yensei Cancer Center, Yonsei University College of Medicine. The mean age of the patients was 49 years (range, $27\~79$ years) and the peak incidence was in the group 50 to 59 years of age. More half of the patients were postmenopausal (46/76= $60.5\%$). Most patients ($76\%$) had abnormal vaginal bleeding either alone or in combination with other symptoms. The proportion of stage IIb was $43.4\%$. There were 4 major histologic subtypes: pure adenocarcinoma (48/76=$63.2\%$), adenosquamous carcinoma (20/76=$26.3\%$), papillary (5/76=$6.6\%$) and clear cell carcinoma (3/76=$3.9\%$). Of the many clinicopathologic variables evaluated for prognosis, the most significant prognostic factors were stage of disease and the size of tumor. The overall 5-year survival rate was $68\%$, and the 5-year survival rates for stage Ib, II and III were $90\%,\;66\%\;and\;54\%$, respectively. Control of pelvic tumors was achieved in $93.8\%,\;90.2\%\;and\;50.0\%$ of cases of stage Ib, II and III disease, respectively. In present study, treatment modalities (radiation therapy alone/combined operative and radiation therapy) did not affect the local control of tumor and the survival.

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Immunogenicity and Safety of Inactivated Influenza Vaccine in Healthy Korean Children and Adolescent (한국의 건강한 소아청소년을 대상으로 한 인플루엔자 사백신의 면역원성과 안전성 연구)

  • Ri, Soohyun;Kim, Mi Jeong;Kim, Yun-Kyung
    • Pediatric Infection and Vaccine
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    • v.25 no.1
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    • pp.35-44
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    • 2018
  • Purpose: This study aimed to evaluate the immunogenicity and safety of a trivalent inactivated influenza vaccine (TIV) among healthy Korean children and adolescents. Methods: From October to December 2008, 65 healthy patients aged 6 months to 18 years who visited Korea University Ansan Hospital for influenza vaccination were enrolled in this study. We measured the hemagglutinin inhibition antibody titers at baseline and 30 days after vaccinating enrollees with split influenza vaccine and calculated the seroprotection rates, geometric mean titers, and seroconversion rates. Local and systemic adverse events were assessed after vaccination. Results: The seroprotection rates against all three viral strains (A/H1N1, A/H3N2, B) were 87.7%, 89.2%, and 89.2% (${\geq}70%$), respectively; seroconversion rates were 44.6%, 73.8%, and 63.1% (${\geq}40%$), respectively; and seroconversion factors were 4.5, 8.4, and 10.5 (>2.5), respectively. The TIV immunogenicity was acceptable according to the CPMP (Committee for Proprietary Medicinal Products) criteria. Although 48 patients (73.8%) reported one or more adverse events, no severe adverse events such as anaphylaxis and convulsion were observed. Forty-two patients (64.6%) reported a local skin reaction, including redness (29.2%), pain (43.1%), or swelling (41.5%) of the injected site, and 26 (40.0%) reported a systemic reaction: fatigue (23.1%), myalgia (20.0%), headache (10.8%), arthralgia (10.8%), chills (9.2%), or fever (7.7%). Conclusions: This study shows that the immunogenicity of the TIV vaccine is acceptable. As there were no serious adverse events aside from local reactions and mild systemic reactions, this vaccine can be safely used among healthy Korean children and adolescents.

The Usefulness of Postoperative Pinhole Bone Scintigraphy in the Assessment of Prognosis after Multiple Drilling or Vascularized Bone Graft in Patients with Avascular Necrosis of Femoral Head (다발성 천공술 및 혈관 부착 골이식술을 시행한 대퇴골두 무혈관성 괴사의 예후: 수술 후 바늘구멍 골신티그라피의 유용성)

  • Chung, Yong-An;Kim, Sung-Hoon;Chun, Kyung-Ah;Park, Young-Ha;Sohn, Hyung-Seon;Chung, Soo-Kyo;Song, Mun-Kab
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.4
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    • pp.405-412
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    • 1999
  • Purpose: It is important to evaluate the healing process of avascular necrosis (AVN) involving femoral head after treatment. The purpose of this study was to assess the usefulness of pinhole bone scintigraphy in the AVN of femoral head after surgery. Materials and Methods: We analyzed the changing pattern of pinhole bone scintigram in 21 femoral heads of 16 patients (14 lesions/11 male, 7 lesions/5 female, mean age: 39.4 yrs) before and after multiple drilling or vascularized bone grafting for AVN of the femoral head. In all patients, pre-operative scintigrams were obtained at 1 to 3 months before treatment and the first post-operative scintigrams were obtained at 1 to 3 months after treatment. All patients were followed for 2 to 4 years after operation. Results: The findings of the pinhole scintigrams were divided into three patterns: 1) curvilinear, 2) scattered spotty and 3) undetermined. The 10 of 11 lesions with curvilinear pattern had good postoperative clinical and radiological follow-up findings. However, all 6 lesions with scattered spotty pattern showed poor postoperative findings, which necessitated total hip joint replacement. Of the 4 lesions with undetermined pattern, 2 required total hip joint replacement. There was significant difference in postoperative prognosis between the curvilinear and scattered spotty patterns (p<0.05). Conclusion: We conclude that the pattern of pinhole bone scintigram obtained within 1 to 3 months after multiple drilling or vascularized bone graft operation is a useful prognostic indicator in the AVN of femoral head.

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Evaluation of Myocardial Oxygen Consumption with $^{11}C$-Acetate and 3D PET/CT: By Applying Recirculation Correction Method and Modified One-Compartmental Tracer Kinetic Modeling ($^{11}C$-Acetate와 3차원 PET/CT를 이용한 심근의 산소 소모량 평가: 재순환 교정법 및 수정 단일구획 추적자 동적 모델 적용)

  • Chun, In-Kook;Hwang, Kyung-Hoon;Lee, Sang-Yoon;Kim, Jin-Su;Lee, Jae-Sung;Shin, Hee-Won;Lee, Min-Kyung;Yoon, Min-Ki;Choe, Won-Sick
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.4
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    • pp.275-284
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    • 2008
  • Purpose: We intended to evaluate myocardial oxygen consumption ($MVO_2)$ by applying recirculation correction and modified one-compartment model to have a reference range of $MVO_2$ in normal young population and to reveal the effect of recirculation on time-activity curve (TAC). Materials and Methods: In nine normal male volunteers with mean age of $26.3{\pm}4.0$, $MVO_2$ was estimated with 925 MBq (25mCi) of $^{11}C$-Acetate (Neuroscience Research Institute, Gachon University of Medicine and Science, Incheon, Korea) and PET/CT (Biograph 6, Siemens Medical Solution, Germany). Analysis software such as $MATLAB^{(R)}$ v7.1 (Mathworks, Inc., United States), $Excel^{(R)}$ 2007 (Microsoft, United States), and $SPSS^{(R)}$ v12.0 (Apache Software Foundation, United States) were used. Twenty three frames were of $12{\times}10$, $5{\times}60$, $3{\times}120$, $2{\times}300's$ duration, respectively. The modified one-compartmental model and the recirculation correction method were applied. Statistical analysis was performed by using Test of Normality, ANOVA and Post-Hoc (Scheffe's) analysis, and p-value less than 0.05 was considered as significant. Results: The normal reference ranges of $MVO_2$ were presented as $3.18-4.64\;{\times}\;10^{-4}\;ml/g/sec$, $1.91-3.94\;{\times}\;10^{-4}\;ml/g/sec$, $4.31-6.40\;{\times}\;10^{-4}\;ml/g/sec$, $2.84-4.53\;{\times}\;10^{-4}\;ml/g/sec$ and $3.42-5.00\;{\times}\;10^{-4}\;ml/g/sec$ in the septum, the inferior wall, the lateral wall, the anterior wall and the entire wall, respectively. In addition, it was noted that the dual exponentiality of the clearance curve is due to the recirculation effect and that the characteristic of the curve is essentially mono-exponential. Conclusion: $^{11}C$-Acetate is a radiotracer worthwhile to assess $MVO_2$. Re-circulated $^{11}C$ can influence TAC of $^{11}C$ in myocadia and so the recirculation correction must be considered when measuring $MVO_2$.