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A Comparative Study on the CT Effective Dose by the Position of Patient's Arm (전신 PET/CT 검사에서 환자의 팔 위치에 따른 CT 유효선량의 비교 연구)

  • Seong, Ji-Hye;Park, Soon-Ki;Kim, Jung-Sun;Park, Seung-Yong;Jung, Woo-Young
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.1
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    • pp.44-49
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    • 2012
  • Purpose: In the whole body PET/CT scan, it is natural to lift the patient's arm for its quality improvement. However, when the lesion is located in head and neck, the arms should be located lower. This study was designed to compare the CT effective dose for each arm position applying Automatic Exposure Control (AEC). Materials and Methods: 45 patients who had $^{18}F$-FDG whole body PET/CT scan were studied with Biograph Truepoint 40 (SIEMENS, GERMANY), Biograph Sensation 16 (SIEMENS, GERMANY), Discovery STe 8 (GE healthcare, USA). The CT effective dose of 15 patients for each equipment was measured and comparatively analyzed in both arm-lifted position and lower-arm position. ImPACT v1.0 program was used as the method of measurement for CT effective dose. For the statistics analysis, Paired t-test which paired with SPSS 18.0 statistic program was applied. Results: In the case of arm-lifted, it was measured as $6.33{\pm}0.93mSv$ for Biograph Sensation 16, $8.01{\pm}1.34mSv$ for Biograph Truepoint 40, and $9.69{\pm}2.32mSv$ for Discovery STe 8. When arms are located lower position, it was measure as $6.97{\pm}0.76mSv$, $8.95{\pm}1.85mSv$, $13.07{\pm}2.87mSv$ for each. CT effective dose according to the arm position was 9.2% for Biograph Truepoint 40, 10.5% for Biograph Sensation 16, and 25.9% for Discovery Ste 8. The statistics analysis showed the meaningful difference ($p$<0.05). Conclusion: For the whole body PET/CT case, CT effective dose applying AEC was decreased the radiation exposure of the patients when the arm was lifted for 15.2% of average value. The patient who has no lesion in head and neck would decrease the artifact occurrence in objective part and lower the CT effective dose. Also, for the patient who had lesion in head and neck, the artifact in objective part can be lower by putting the arms down, the fact that CT effective dose increases should be concerned in its whole body PET/CT scan.

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Consideration of Shoulder Joint's Image with the Changed Tube Angle of the Shoulder Oblique Projection in Supine Position (Supine 자세에서 Shoulder oblique촬영시 Tube angle 변화에 따른 Shoulder joint에 대한 고찰)

  • Seo, Jae-Hyun;Choi, Nam-Gil
    • Journal of radiological science and technology
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    • v.31 no.2
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    • pp.109-114
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    • 2008
  • There is a standard shoulder oblique method (Grashey method) available to view the shoulder joint. This method projects AP view of the shoulder joint so that the Humerus head's subuxation or joint degeneration can be easily visualized. However, in this view, the patients, with supine or sitting or erect position, have to keep their body obliquely. Whereas, the patients who are not well or operated, usually feel very uncomfortable to keep their body in this position and hence, we need other persons' help and much efforts will be needed to get the good quality shoulder joint view. Therefore, we thought of examining a method which shows the joint well by angling the tube to Medio-Lateral direction and without keeping the patients' one side upward in supine position. For this study, total 15 subjects with no history of neurological or psychiatric illness, were recruited for examinations. They consisted of 9 males and 6 females. Statistic group analysis was performed with ANOVA test. Scores of the evaluation of the experts were $1.10{\pm}0.54$ at $25^{\circ}$, $2.50{\pm}0.50$ at 30^{\circ}$, $2.85{\pm}0.36$ at $35^{\circ}$ and $2.33{\pm}0.47$ at $40^{\circ}$, respectively, and they were significant(p<0.05, Table 1). Joint space of the Humerus head and Scapula were well distinguished at $35^{\circ}$, $30^{\circ}$ and $40^{\circ}$ with the almost same score. However, the degree of distortion at $40^{\circ}$ was more severe than that at $30^{\circ}$. Ultimately, $30-35^{\circ}$ views were shown to yield good quality shoulder oblique images. In conclusion, this method may be very useful for the patients who are uncomfortable and for the emergency patients. In order to get similar or comparable view, the same X-tube angle is recommended to be used before and after the operation. Therefore, we hope that this new angled method seems to be efficient.

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Clinical Study of Rotavirus Gastroenteritis in the Last 2 Years (최근 2년간 로타바이러스 장염에 대한 임상적 연구)

  • Kim, Hyoung Sik;Jang, Myong Wan;Kim, Cheol Hong;Lee, Hyun Hee;Yoo, Hwang Jae
    • Clinical and Experimental Pediatrics
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    • v.48 no.10
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    • pp.1116-1120
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    • 2005
  • Purpose : Although the rotavirus-related neonatal death occurred in western part of Kyeonggi Province recently, there were just a few reports about rotavirus gastroentertis in domestic since 2000. We proposed to investigate changes of epidemiology and clinical features of rotavirus gastroenteritis for the last 2 years. Methods : We selected 166 patients diagnosed as gastroenteritis from January, 2002 to July, 2003 and reviewed the admission records retrospectively such as age distribution, sex ratio, seasonal distribution, admission period, laboratory data and dehydration type in the rotavirus group(RVG) and non-RVG. Results : The percentage of patient under 3 years was 77% on RVG. The non-RVG showed even age distribution(P<0.05). In RVG, patients occurred in March frequently and 52% occurred from January to March. In non-RVG, patients occurred highly in February and July(P<0.05). The average of admission period was higher in RVG than non-RVG(P<0.05). The percentage of patient admitted for over 10 days was 8% in the RVG. In dehydration severity, the RVG showed mild(51%), moderate(44%) and severe(5%) respectively, but non-RVG showed only mild dehydration(P<0.05). The laboratory findings' did not have statistic significance between RVG and non-RVG. Conclusion : Compared to the previous studies, seasonal peak prevalence of rotavirus gastroenteritis changed from autumn to spring and patients over 3 years increased. Therefore, we suggest that there are variable serotypes of rotavirus domestically and there is a need for reinvestigation about clinical features and serotypes of rotavirus gastroenteritis.

Statistical Study on Respiratory Stability Through RPM Signal Analysis according to Patient Position Under Radiation Therapy and Device (방사선 치료 환자의 자세 및 Device에 따른 RPM 신호 분석을 통한 호흡 안정성의 통계적 고찰)

  • Park, Myung-Hwan;Seo, Jeong-Min;Choi, Byeong-Gi;Shin, Eun-Hyeok;Song, Gi-Won
    • The Journal of Korean Society for Radiation Therapy
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    • v.23 no.2
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    • pp.83-90
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    • 2011
  • Purpose: This study statistically analyzed the difference of the stability of maintaining a respiratory period shown according to position and use of a device to search the tendency and usefulness of a device. Materials and Methods: The study obtained respiratory signals which maintained a respiratory period for 20 minutes each supine and prone position for 11 subjects. The study obtained respiratory signals in a state of using a belly board for 7 patients in a bad condition of a respiratory period in a prone position to analyze a change in respiration and the stability before and after the use of a device. Results: The supine part showed 54.5%, better than the prone part of 36.4% in a case that the stability for maintaining a respiratory period was in a good condition as a fixed respiratory period was well maintained according to the position. 6 patients (85%) showed a maintenance pattern of a respiratory period significantly different before the use and 4 patients showed a significantly good change in the stability for maintaining a respiratory period as a result that belly boards were used for 7 patients that the maintenance of a respiratory period was not in a good condition on a prone position. Conclusion: It seemed that this study could contribute to the maintenance of respiratory period and of respiratory stability as the optimal position for maintenance of respiration and the use of a device such as a belly board were decided through statistic analysis of respiratory signals and its application even if patient position and use of device were decided by the beam arrangement a treatment part of a patient, location of a target, and an expected plan.

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Flip Angle of the Optimal T1 Effect Using FLASH Pulse Sequence at 3T Abdominal MRI (FLASH를 이용한 3T 복부검사에 있어서 최적의 T1효과를 위한 적정 Flip Angle)

  • Han, Jae-Bok;Choi, Nam-Gil
    • Journal of radiological science and technology
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    • v.32 no.1
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    • pp.101-106
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    • 2009
  • Purpose of this study is to compare the signal intensity (SI) and CNR with T1 weighted image using FLASH at 3T abdominal MRI by varying flip angle (FA). Totally 20 patients (male : 12, female : 8, Age : $28{\sim}63$ years with mean : 51) were examined by 3 Tesla MR scanner (Magnetom Tim Trio, SIEMENS, Germany) with 8 channel body array coil between september and October 2008. Imaging parameters were as follows : FLASH sequence, TR : 120 ms, TE : minimum, FOV (field of view) : $360{\times}300\;mm$, Matrix : $256{\times}224$, slice : 6 mm, scan time : 15 sec and Breath-hold technique. Abdominal image, with a 50 ml syringe filled with water placed in the FOV measuring the water signal, were acquired with varying FA through $10^{\circ}$ to $90^{\circ}$ with $10^{\circ}$ interval. SI's were measured three times at liver parenchyme, water, spleen and background and averaged. The CNR's were measured between the ROIs (region of interest). Statistic analysis was performed with ANOVA test using SPSS software (version 17.0). Less than FA $30^{\circ}$, abdominal images were severely inhomogeneity. Especially, T1 effect of water signal was weak. As the flip angle increased, the signal intensity decreased at all the regions. Especially, flip angle of the highest signal intensity was observed with $40^{\circ}$ at the liver parenchyme, $20^{\circ}$ at water, $30^{\circ}$ at the spleen, respectively. The CNR between liver and water was -60.92 at FA $10^{\circ}$ and 15.16 at FA $80^{\circ}$. The CNR between liver and spleen was -3.18 at FA $10^{\circ}$ and 9.65 at $80^{\circ}$. In conclusion, FA $80^{\circ}$ is optimal for T1 weighted effect using FLASH pulse sequence at 3.0 T abdominal MRI.

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The Association of Social Support with Health Status and Health Behavior among Rural Aged Population (일부 농촌 지역 노인의 사회적 지지와 건강수준 및 건강행태와의 관련성)

  • Jeon, Bo-Young;Lee, Hye-Jae;Shon, Chang-U;Kim, Nam-Kwon;Kim, Ae-Ryun;Park, Ji-Eun;Lee, Eun-Sang;Lee, Jeong-Wha;Choi, Ju-Hyun
    • Journal of agricultural medicine and community health
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    • v.34 no.1
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    • pp.13-23
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    • 2009
  • Objective: The objective of this study was to evaluate the association of social support with health status and health behavior. Methods: This study was conducted with 79 elderly people in Gunja-ri, Dongsan-myun, Chuncheon. We performed face to face interview which was composed of socio-demographic characteristics, social support, health status and health behavior. The association between social support and result variables was analysed by Chi-square test and logistic regression. We used SAS ver9.1 for statistic analysis. Results: Mean age of the study population was 72.0$\pm$7.0, social support score was 14.3$\pm$4.7 with full marks of 20 and 36.25% of the total population were shown to have depression. When the social support score was changed, depression (p=0.0007) and physical exercise (p=0.0312) showed significant difference. The self-rated health status was significantly related to the relationship with family members (OR=0.25, 95% CI=0.07-0.95) and the quality of sleep was also significantly associated to the relationship with family members (OR=0.21, 95% CI=0.06-0.73). The physical exercise was done significantly less in the group without close friends than in the group with many close friends (OR=0.21, 95% CI=0.05-0.94) and the depression was significantly more in the group without community participation than in the group with community participation (OR=4.79, 95% CI=1.62-14.15). Conclusions: Through this study, we could conclude that the social support factors are associated with health status and health behavior. Therefore, to improve the health status of rural elderly, we need to approach to develop social support.

The Clinical Results of ACL Reconstruction with Tibialis Allograft Using Hybrid Femoral Fixation and $Retroscrew^{(R)}$ (Hybrid 대퇴 고정과 $Retroscrew^{(R)}$를 사용한 동종 경골건 이용 전방 십자 인대 재건술의 임상적 결과)

  • Kim, Doo-Sub;Rah, Jung-Ho
    • Journal of the Korean Arthroscopy Society
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    • v.13 no.1
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    • pp.8-13
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    • 2009
  • Purpose: We used tibialis allograft for the reconstruction of ACL and used Hybrid femoral fixation utilizing $Endobutton^{(R)}$ and $Rigidfix^{(R)}$ for femoral fixation, and used $Retroscrew^{(R)}$ and additional fixation for tibial fixation to evaluate the clinical results. Materials and Methods: The ACL reconstruction were performed from February 2004 to February 2007 utilizing Hybrid femoral fixation and $Retroscrew^{(R)}$ and 32 patients, 32 cases which were available for year-long observation (12 to 25 months). The clinical results (Lysholm knee score, IKDC grade) and the radiologic results(bone tunnel expansion, Telos anterior displacement test) were evaluated. Results: The Lysholm knee score was improved from the average of $67.9{\pm}5.4$ points (range: 51~77) before operation and to $94.1{\pm}6.8$ points (range: 68~98) at the last follow up (p<0.05). 22 cases (69%) were evaluated normal (A), 9 cases (28%) were evaluated nearly normal (B) and only 1 case (3%) was evaluated not normal (C) at IKDC final evaluation and no case was evaluated abnormal. From $Telos^{(R)}$ stress x-ray evaluation, difference from the opposite knee was improved average 13.2 mm{\pm}5.8 (range: 6~21 mm) to average $3.4\;mm{\pm}2.8$ (range: 0~11 mm) after operation (p<0.05). The femoral and tibial tunnel were widened by 18.7% and 9.6% in the AP view and 12.4% and 8.5% in the lateral view, respectively (p<0.05). However, any statistic significance was not observed between bone tunnel expansion and knee joint functions (p>0.05). Conclusion: An ACL reconstruction with tibialis allograft using Hybrid femoral fixation and $Retroscrew^{(R)}$ enabled anatomical fixation of the graft tendon with satisfactory clinical results.

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The Factors Influencing the Asthenopia of Emmetropia with Phoria (사위를 가진 정시안의 안정피로에 영향을 미치는 요인)

  • Kim, Jung-Hee;Lee, Dong-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.10 no.1
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    • pp.71-82
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    • 2005
  • The aim of this study was to provide fundamental data for the factors influencing the asthenopia of emmetropia with phoria and alleviation of asthenopia. A total of 348 subjects, aged between 19 and 30 years old, who had no strabismus, an eye trouble or whole body disease, were examined using corrected visual acuity, corrected diopter, stereopsis and suppression tests from September of 2002 to September of 2004. We excluded 21 subjects for the following reasons: if they had an amblyopia affecting binocular vision or inaccurate data. After these exclusions, 327 subjects remained. We then individually measured the refractive error correction, pupillary distance, optical center distance, phoria, convergence, accommodation and the AC/A as well as the asthenopia during binocular vision using a questionnaire. After analysis of factors affecting asthenopia, we also examined the reductive effect of a prism on the asthenopia in subjects who had asthenopia. To determine the factors affecting asthenopia during binocular vision, statistic analyses were carried out using the Chi-square test and the multivariate Logistic regression model. The results of this study were as follow. For asthenopia during near binocular vision of emmetropia with phoria, in case of the lower the accommodation and convergence, a significantly higher rate of asthenopia was observed (p<0.001). When the AC/A is lower, the higher the rate of asthenopia was observed but not significantly and there was no association between phoria and asthenopia. When the multivariate logistic regression model was used to determine factors affecting binocular vision of emmetropia with phoria, in case of the lower accommodation and convergence, a significantly higher rate of asthenopia was observed. when the phoria is esophoria or higher exophoria, or when the AC/A is lower than normal, the higher the rate of asthenopia was observed but not significantly and there was no association between phoria. AC/A and asthenopia. Therefore accommodation and convergence could be predictive factors for asthenopia during near distance binocular vision. Prism was used among' subjects who had asthenopia during near distance binocular vision, the symptom of asthenopia was eased up to 74.2% in emmetropia with phoria.

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Studies on Application Method and Safety of Macrogranule(GG) Herbicide for Remote-controlled Aerial Application (무인헬기용 Macrogranule(GG) 제초제의 안정성 및 살포방법 연구)

  • Yoon, Cheol-Su;Bae, Chang-Hyu;Lee, Sheong-Chun;Kim, Kyung-Hyun;Lee, Kye-Hwan;Cho, Tae-Kyoung;Hwang, In-Cheon
    • Korean Journal of Weed Science
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    • v.31 no.3
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    • pp.294-307
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    • 2011
  • This experiment carried out to confirm characteristics of macrogranule (GG) for herbicidal efficacy by using remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field, application methods, and application times of formulation types. Particle of 500 g GG having average diameter of 2.5~3 mm was over 85 percent, the bulk density of the particle was $0.2\sim0.4g\;mL^{-1}$ and the particle was water floating granule. Active ingredients and external form of halosulfuronmethyl+mefenacet GG remained stable under condition of storage stability test. The disintegration time of the GG was faster as the water temperature was increased. But disintegration time was not affected by pH on the water conditions. By using hand, spoon and power applicator, drift distances of GG were 4~5m, 7 m and 10~12 m, respectively. GG showed good herbicidal efficacy and plant safety in all of the application methods such as, using hand, spoon, power applicator and RCAA. Application times of GG, GR, SC and TB by hand in $4,000m^2$ were 38 min. 4 sec, 42 min. 20 sec, 38 min. 10 sec and 21 min. 4 sec, respectively, but application time of GG by using RCAA was 1 min 32 sec. According to appearance and characteristics of formulation types, suspension concentrate (SC) and GG were possible formulation types for RCAA.

A Study on Medical Waste Contaminated by Radioactivity in Nuclear Medicine Department (핵의학과 일반 의료폐기물에서의 방사능 오염에 관한 고찰)

  • Yoo, Jae-Sook;Jang, Jung-Chan;Lee, Dong-Hoon;Cha, Min-Kyeong;Nam, Ki-Pyo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.70-74
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    • 2011
  • Purpose: In the Nuclear Medicine department of Asan Medical Center, radioactive waste has been disposed of by using several disposal boxes designed for nuclear waste. However, some quantity of radioactivity has been detected occasionally due to some radiologists' carelessness not only from radioactive waste, but also from medical waste such as uncontrolled radioactive waste related to patients, poly gloves or saline solution bottles from radiopharmaceuticals laboratory. Thus, this study is going to suggest a solution to maintain the medical wastes made from controlled areas that can be below maximum permissible surface dose limits by finding the cause of radioactive contamination. Materials and methods: This study was taken place in 17 different places-2 medical wastebaskets in the waiting room, 2 medical wastebaskets in the PET room, 5 medical wastebaskets in the in vitro laboratory and 6 medical wastebaskets in the radiopharmaceuticals laboratory of the East building, 2 medical wastebaskets in the waiting room of the New building of Nuclear Medicine Department in Asan Medical Center from April to August 2010. Mean radioactivity and its standard deviation of each place have been found by measuring surface contamination of medical wastebaskets and backgrounds twice a week, totaling 30 times. An independent t-test of SPSS (Ver. 12.0) statistic program has been used for statistical analysis. Swabs, saline solution bottles and poly gloves collected from each place also measured 30 times, respectively. Results: This study analyzed medical waste and the backgrounds of each place by using survey meter detectors that significant differences of five places did not exist, but existed statistically in twelve places (p<0.05). Also, swabs, saline solution bottles and poly gloves collected from each radioactive waste partly exceed the legal dose limit as a result of measuring by a gamma counter. Conclusion: Backgrounds and the surface doses of radioactive disposal box in all 17 places measured by the survey meter did not exceed the legal dose limit; however, it obviously showed that there were prominent differences in 12 places. Assuming that the cause of the differences was swabs, saline solution bottles and gloves, we examined them by gamma counter, and the results showed remarkably high doses of radioactivity. Consequently, swabs and poly gloves which are normally disposed in the general medical waste box should be disposed in the radioactive waste box furnished by radiopharmaceuticals laboratory. Also, saline solution discharged from radioactive pharmaceutical places is considered as radioactive liquid waste so that it should be disposed of by the septic tank specifically designed for radioactive liquid.

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