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Increase of Tc-99m RBC SPECT Sensitivity for Small Liver Hemangioma using Ordered Subset Expectation Maximization Technique (Tc-99m RBC SPECT에서 Ordered Subset Expectation Maximization 기법을 이용한 작은 간 혈관종 진단 예민도의 향상)

  • Jeon, Tae-Joo;Bong, Jung-Kyun;Kim, Hee-Joung;Kim, Myung-Jin;Lee, Jong-Doo
    • The Korean Journal of Nuclear Medicine
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    • v.36 no.6
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    • pp.344-356
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    • 2002
  • Purpose: RBC blood pool SPECT has been used to diagnose focal liver lesion such as hemangioma owing to its high specificity. However, low spatial resolution is a major limitation of this modality. Recently, ordered subset expectation maximization (OSEM) has been introduced to obtain tomographic images for clinical application. We compared this new modified iterative reconstruction method, OSEM with conventional filtered back projection (FBP) in imaging of liver hemangioma. Materials and Methods: Sixty four projection data were acquired using dual head gamma camera in 28 lesions of 24 patients with cavernous hemangioma of liver and these raw data were transferred to LINUX based personal computer. After the replacement of header file as interfile, OSEM was performed under various conditions of subsets (1,2,4,8,16, and 32) and iteration numbers (1,2,4,8, and 16) to obtain the best setting for liver imaging. The best condition for imaging in our investigation was considered to be 4 iterations and 16 subsets. After then, all the images were processed by both FBP and OSEM. Three experts reviewed these images without any information. Results: According to blind review of 28 lesions, OSEM images revealed at least same or better image quality than those of FBP in nearly all cases. Although there showed no significant difference in detection of large lesions more than 3 cm, 5 lesions with 1.5 to 3 cm in diameter were detected by OSEM only. However, both techniques failed to depict 4 cases of small lesions less than 1.5 cm. Conclusion: OSEM revealed better contrast and define in depiction of liver hemangioma as well as higher sensitivity in detection of small lesions. Furthermore this reconstruction method dose not require high performance computer system or long reconstruction time, therefore OSEM is supposed to be good method that can be applied to RBC blood pool SPECT for the diagnosis of liver hemangioma.

Effect of Carrier on Labeling and Biodistribution of Re-188-Hydroxyethylidene diphosphonate (담체가 Re-188-Hydroxyethylidene Diphosphonate의 표지와 생체내분포에 미치는 영향)

  • Chang, Young-Soo;Jeong, Jae-Min;Kim, Bo-Kwang;Cho, Jung-Hyuk;Lee, Dong-Soo;Chung, June-Key;Lee, Seung-Jin;Jin, Ren-Jie;Lee, Sang-Eun;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.4
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    • pp.344-352
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    • 2000
  • Purpose: Re-188-Hydroxyethylidene diphosphonate (HEDP) is a new cost-effective agent for systemic radioisotope therapy of metastatic bone pain. We investigated the influence of carrier for labeling and biodistribution of Re-188-HEDP using HEDP kit with or without carrier ($KReO_4$). Materials and Methods: The kits (HEDP 15 mg, gentisic acid 4 mg and $SnCl_2.2H_2O_2$ 4.5 mg) with or without carrier ($KReO_4$ 0.1 mg) were labeled with Re-188 solution, made available from an in-house generator by boiling for 15 min. We compared the labeling efficiency and stability of carrier-added and carrier-free preparations of Re-188-HEDP Biodistribution and imaging studies of each preparation were performed in ICR mice ($1.85{\sim}3.7MBq/0.1ml$) and SD rats ($74.1{\sim}85.2MBq/0.5ml$). Results: The carrier-added preparation showed high labeling efficiency (95% at pH 5) and high stability in serum (88%, 3 hr). However, the carrier-free preparation showed low labeling efficiency (59% at pH 5) and low stability (43%, 3 hr). The carrier-added preparation showed high uptake in bone and low uptake in stomach and kidneys. However, the carrier-free preparation showed lower uptake in bone and higher uptake in both stomach and kidneys, which is supposed to be due to released perrhenate. The carrier-added preparation also showed better images with higher skeletal accumulation, lower uptake in other organs and lower soft tissue uptake than the carrier-free preparation. Conclusion: The results of these studies clearly demonstrate that addition of carrier perrhenate is required for high labeling efficiency, stability, bone uptake and good image quality of Re-188-HEDP.

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The Effect of Repetitive Insertion and Pullout of Spinal Screws on Pullout Resistance : A Biomechanical Study (척추 수술에 사용되는 나사못의 반복 삽입과 인출이 인장항력에 미치는 영향 : 생체 역학적 연구)

  • Bak, Koang Hum;Ferrara, Lisa;Kim, Kwang Jin;Kim, Jae Min;Kim, Choong Hyun;Benzel, Edward C.
    • Journal of Korean Neurosurgical Society
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    • v.30 no.2
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    • pp.131-136
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    • 2001
  • Object : The clinical uses of screws are increasing with broader applications in spinal disorders. When screws are inserted repeatedly to achieve optimal position, tips of screw pitch may become damaged during insertion even though there are significant differences in the moduli of elasticity between bone and titanium. The effect of repeated screw insertion on pullout resistance was investigated. Methods : Three different titanium screws(cortical lateral mass screw, cancellous lateral mass screw and cervical vertebral body screw) were inserted into the synthetic cancellous material and then extracted axially at a rate of 2.4mm/min using Instron(Model TT-D, Canton, MA). Each set of screws was inserted and pulled out three times. There were six screws in each group. The insertional torque was measured with a torque wrench during insertion. Pullout strength was recorded with a digital oscilloscope. Results : The mean pullout force measurements for the cortical lateral mass screws($185.66N{\pm}42.60$, $167.10N{\pm}27.01$ and $162.52 N{\pm}23.83$ for first, second and third pullout respectively : p=0.03) and the cervical vertebral body screws($386.0N{\pm}24.1$, $360.2N{\pm}17.5$ and $330.9N{\pm}16.7$ : p=0.0024) showed consecutive decrease in pullout resistance after each pullout, whereas the cancellous lateral mass screws did not($194.00N{\pm}36.47$, $219.24N{\pm}26.58$ and 199.49N(36.63 : p=0.24). The SEM after insertion and pullout three times showed a blunting in the tip of the screw pitch and a smearing of the screw surface. Conclusions : Repetitive screw insertion and pullout resulted in the decrease of pullout resistance in certain screws possibly caused by blunting the screw tip. This means screw tips suffer deformations during either repeated insertion or pullout. Thus, the screws that have been inserted should not be used for the final construct.

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Chardin's Genre Paintings of Child Education: The Enlightenment Views on Children of the French Bourgeois Class in the 18th Century (샤르댕의 아동 교육 장르화 - 18세기 프랑스 부르주아의 계몽주의적 아동관)

  • Ko, Yu-Kyoung
    • The Journal of Art Theory & Practice
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    • no.8
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    • pp.33-58
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    • 2009
  • This paper examines four genre paintings on the subject of child education by Jean-Baptiste-Sim${\'{e}}$on Chardin(1699-1779). The Governess, The Diligent Mother, Saying Grace, and The Morning Toilette garnered critical attention after they were exhibited in the Salon from 1739 to 1741. After the exhibition, the paintings were made into prints and frequently sold to members of the bourgeois class in Paris. The iconographical details of Chardin's genre paintings have, thus far, been compared to Dutch genre pictures of the seventeenth century. Further, most studies conducted on Chardin's paintings focus on formal analysis rather than the historical and social contexts. Through attempting social-contextual readings of Chardin's educational series, this paper argues that the significance of Chardin's painting series of child education lies in his representation of the ideal French bourgeois family and the standard of early childhood education in the eighteenth-century French Enlightenment period. In each of the four child education paintings, Chardin depicted a mother with children in a domestic space. Even though this theme derives from traditional Dutch genre paintings in the seventeenth century, the visual motifs, the pictorial atmosphere and the painting techniques of Chardin all project the social culture of eighteenth century France. Each painting in the child education series exemplifies respectively the attire of a French gentlemen, the social view on womanhood and the education of girls, newly established table manners, and the dressing up culture in a 'toilette' in eighteenth century France. Distinct from other educational scenes in previous genre paintings, Chardin accentuated the naive and innocent characteristics of a child and exemplified the mother's warmth toward that child in her tender facial expressions and gesturing. These kinds of expressions illustrate the newly structured standard of education in the French Enlightenment period. Whereas medieval people viewed children as immature and useless, people in the eighteenth century began to recognize children for their more positive features. They compared children to a blank piece of paper (tabula rasa), which signified children's innocence, and suggested that children possess neither good nor bad virtues. This positive perspective on children slowly transformed the pedagogical methods. Teaching manuals instructed governesses and mothers to respect each child's personality rather than be strict and harsh to them. Children were also allotted more playtimes, which explains the display of various toys in the backgrounds of Chardin's series of four paintings. Concurrently, the interior, where this exemplary education was executed, alludes to the virtue of the bourgeois's moderate and thrifty daily life in eighteenth century France. While other contemporary painters preferred to depict the extravagant living space of a French bourgeoisie, Chardin portrayed a rather modest and cozy home interior. In contrast to the highly decorated living space of aristocrats, he presented the realistic, humble domestic space of a bourgeois, filled with modern household objects. In addition, the mother is exceptionally clad in working clothes instead of fashionable dresses of the moment. Fit to take care of household affairs and children, the mother represents the ideal virtues of a bourgeois family. It can be concluded that the four genre paintings of child education by Chardin articulate the new standards of juvenile education in eighteenth century France as well as the highly recognized social virtues between French bourgeois families. Thus, Chardin's series of child education would have functioned as a demonstration of the ideal living standards of the bourgeois class and their emphasis on early childhood education in the French Enlightenment period.

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The Effects of Ginseng Saponin on Relaxation of Smooth Muscle in the Lower Urinary Tract and the Corpus Cavernosum (인삼 사포닌이 하부요로와 음경해면체 평활근의 이완작용에 미치는 효과)

  • Jung, Hee-Chang;Oh, Tae-Hee
    • Journal of Yeungnam Medical Science
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    • v.23 no.1
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    • pp.52-61
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    • 2006
  • Background: Korean ginseng (KG) has been used as a general tonic, and for voiding dysfunction for a long time in oriental society. However, scientific basic studies on the use of KG, have been rare, especially for voiding and erectile dysfunction. This study was performed to investigate the effects of KG on voiding and erectile function by examining the effects of total saponin (TS) on the bladder, urethral and penile cavernosal smooth muscle. Materials and methods: To examine the effects of TS, NewZeland white rabbits were used to obtain tissue strips from the smooth muscle of the bladder, proximal urethra and corpus cavernosum. Adult Sprague Dawley rats were used to examine the changes in urodynamic findings and penile erection after administration of TS. Results: In proximal urethral strips, the rate of relaxation of the proximal urethra was increased from $9.0{\pm}2.9$ to $33.7{\pm}4.8%$ in a dose-dependent manner when the concentration of TS was added accumulatively from 0.25 mg/ml to 4.0 mg/ml (p<0.05). However, no significant response was observed in the bladder strips within these concentration ranges. For the corpus cavernosal strips, the rate of relaxation ranged from $5.8{\pm}2.1$ to $36.7{\pm}5.8%$, increasing in a dose-dependent manner when TS was increased from 1.0 mg/ml to 4.0 mg/ml (p<0.05). After administration of 0.1 ml of TS (32 mg/ml) in the rat, the bladder pressure was $37.5{\pm}8.5$ mmHg at $52.1{\pm}7.0$ sec. during isovolumetric bladder contraction, showing no significant differences from $35.7{\pm}7.8mmHg$ and $50.7{\pm}7.2$ sec, respectively, before treatment. However, when 0.1 ml of TS (32 mg/ml) was administered, the relative reduction of urethral pressure was $6.9{\pm}0.5mmHg$ at $62{\pm}7.5$ sec, which was significantly higher compared to $4.6{\pm}1.1mmHg$ at $45{\pm}10$ sec before treatment (p<0.05). For the cavernosal injection study, the change in intracavernosal pressure (${\Delta}ICP$) was examined after administering 0.1 ml of TS. The cumulative additions of TS at concentrations from 0.5 mg/ml to 32 mg/ml increased ${\Delta}ICP$ from $1.3{\pm}0.5$ to $21.3{\pm}7.8mmHg$ in a dose-dependent manner (p<0.05). The duration of tumescence was from $0.3{\pm}0.1$ to $5.2{\pm}0.2$ min, showing dose-dependent increase (p<0.05). Furthermore, the cumulative addition of TS at concentrations from 0.5 mg/ml upto 32 mg/ml did not cause any significant change in systemic blood pressure. Conclusion: These results suggest that ginseng improves voiding functions, which is mainly achieved by TS relaxing the proximal urethra, the most important part of the bladder outlet function. In addition, ginseng safely induced a penile erection hemodynamically by relaxing the corpus cavernosum.

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Final Impact of Anti-Vascular Endothelial Growth Factor Treatment in Age-related Macular Degeneration (연령관련황반변성 환자에서 항혈관내피성장인자의 치료 방법과 재정 영향 분석)

  • Yang, Jangmi;Shin, Sang Jin;Suh, Jae Kyung;Cho, Songhee;Tchoe, Hajin;Kang, Min Joo;Jee, Donghyun
    • Journal of The Korean Ophthalmological Society
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    • v.59 no.11
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    • pp.1039-1048
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    • 2018
  • Purpose: To evaluate the effects of anti-vascular endothelial growth factor (VEGF) treatment on the healthcare-related finances of patients with age-related macular degeneration. Methods: Changes in health care financing due to newly introduced benefit standards were predicted over the coming 5-year period (2018-2022). We also analyzed the financial impact of scenarios in which agents similar to anti-VEGF, such as the over-licensed drug bevacizumab, were introduced. For this purpose, the future number of patients receiving anti-VEGF treatments was estimated for various scenarios based on National Health Insurance Corporation claims data followed by an estimate of the financial burden. Results: In the case of age-related macular degeneration, the current standard of care (14 times in a lifetime) was maintained in scenario 1. In 2018, the insurance budget for the coming 5-year period was estimated at approximately 440.3 billion won. The insurance cost for that period was estimated at approximately 560.1 billion won under the revised standard of December 2017 (scenario 2). For scenarios wherein, after 2020, similar treatments (scenario 3) and bevacizumab (scenario 4) were introduced, the estimated health insurance costs were 521 billion won and 419.7 billion won, respectively. Conclusions: Health insurance costs are projected to increase substantially due to the elimination of the 14 time pay standard; however, the actual budget will only moderately increase, due to new limitations of visual acuity ${\leq}0.1$ or in case of scarring/atrophic lesions. Clinically similar agents and bevacizumab could be considered as alternatives to anti-VEGF treatment for age-related macular degeneration.

Clinical Effects of an Improved Pump Reaction Rate and Automatic Occlusion Sensing System in Phacoemulsification (수정체유화장치의 초음파 출력속도 및 자동막힘감지 기능 향상의 술 후 임상결과 비교)

  • Kim, You Na;Lee, Jin Ah;Kim, Jae Yong;Kim, Myoung Joon;Tchah, Hung Won
    • Journal of The Korean Ophthalmological Society
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    • v.59 no.11
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    • pp.1017-1023
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    • 2018
  • Purpose: A recently introduced phacoemulsification system, the WhiteStar $Signature^{(R)}$ PRO, has demonstrated improved nucleus followability and cutting efficiency via an improved pump regulator with a higher reaction response and an automatic occlusion sensing system. In this study, we compared various phacoemulsification parameters between the new system and an older version of the device. Methods: A total of 80 eyes of 68 patients with cataracts who had undergone phacoemulsification by a single surgeon were included in this study. Forty eyes of patients underwent phacoemulsification using the older $Signature^{(R)}$ system (WhiteStar); these patients were classified as the control group. Another 40 eyes of patients underwent phacoemulsification with the newer enhanced system, the WhiteStar $Signature^{(R)}$ PRO; these patients were assigned to the experimental group. During the operation, operative parameters, including the effective phaco time (parameter of effective phaco time with a specific coefficient for the transversal movement expressed in seconds, EFX), ultrasound time (seconds [s]), effective phacoemulsification time (EPT, s), average phacoemulsification power (AVG, %), and balanced salt solution usage, were measured to determine the performance enhancement offered by the updated system. Central corneal thickness was measured before and after surgery to compare corneal edema. The relationships between the two groups were analyzed using an independent t-test. Results: The Signature $PRO^{(R)}$ system showed a lower EFX (p < 0.001), a shorter EPT (p < 0.001), and a smaller AVG (p < 0.001). Postoperative corneal thickness did not differ significantly between the two groups. Conclusions: Comparing the efficacy of the improved reaction speed of the device and automatic occlusion sensing system in performing phacoemulsification, the updated Signature $PRO^{(R)}$ system demonstrated superior followability and cutting efficiency regardless of nuclear cataract hardness.

Fragment Analysis for Detection of the FLT3-Internal Tandem Duplication: Comparison with Conventional PCR and Sanger Sequencing (FLT3-ITD 검출을 위한 절편분석법: 일반 중합효소연쇄반응 및 직접염기서열분석법과의 비교)

  • Lee, GunDong;Kim, Jeongeun;Lee, SangYoon;Jang, Woori;Park, Joonhong;Chae, Hyojin;Kim, Myungshin;Kim, Yonggoo
    • Laboratory Medicine Online
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    • v.7 no.1
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    • pp.13-19
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    • 2017
  • Background: We evaluated a sensitive and quantitative method utilizing fragment analysis of the fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD), simultaneously measuring mutant allele burden and length, and verified the analytical performance. Methods: The number and allelic burden of FLT3-ITD mutations was determined by fragment analysis. Serial mixtures of mutant and wild-type plasmid DNA were used to calculate the limit of detection of fragment analysis, conventional PCR, and Sanger sequencing. Specificity was evaluated using DNA samples derived from 50 normal donors. Results of fragment analysis were compared to those of conventional PCR, using 481 AML specimens. Results: Defined mixtures were consistently and accurately identified by fragment analysis at a 5% relative concentration of mutant to wild-type, and at 10% and 20% ratios by conventional PCR and direct sequencing, respectively. No false positivity was identified. Among 481 AML specimens, 40.1% (193/481) had FLT3-ITD mutations. The mutant allele burden (1.7-94.1%; median, 28.2%) and repeated length of the mutation (14-153 bp; median, 49 bp) were variable. The concordance rate between fragment analysis and conventional PCR was 97.7% (470/481). Fragment analysis was more sensitive than conventional PCR and detected 11 additional cases: seven had mutations below 10%, three cases represented conventional PCR failure, and one case showed false negativity because of short ITD length (14 bp). Conclusions: The new fragment analysis method proved to be sensitive and reliable for the detection and monitoring of FLT3-ITD in patients with AML. This could be used to simultaneously assess ITD mutant allele burden and length.

The Changes of Smart Device Usage Status in Early Childhood: Comparison of 2015-2016 and 2017 Studies (유아 스마트 기기 사용 현황의 변화: 2015-2016년과 2017년의 연구 결과 비교)

  • So, Hyejin;Lim, Sungmin;Cho, Sang Yeun;Koh, Min Suk;Moon, Jin-Hwa
    • Journal of the Korean Child Neurology Society
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    • v.26 no.4
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    • pp.251-262
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    • 2018
  • Purpose: This study aimed to identify changes in smart device usage trends of young children using two studies conducted in 2015-2016 and 2017 respectively. Methods: We compared the data of the previous study of 130 children (Group A) and the new study of 162 children (Group B). The children and parents were recruited from kindergartens in Seoul and Guri/Namyangju cities. We used the "Parental questionnaire for smart device usage status." Results: There were some changes in the smart device usage in young children and parental perception. In the 2017 study, smart device usage time increased during weekends (P<0.05) and the usage with siblings decreased (P<0.05). In 2017, the smart device was mostly used when children had to be quiet without disturbing others (36.8%). No significant difference existed in the main purpose of use: watching video clips (79.3% vs 76.6%). Overall control of the usage was still largely exercised by mothers; however, when using applications, mothers still only helped the children on request (51.8% vs 49.7%). Regarding the effect of smart device on children, responses of "not knowing" decreased and "will be negative" and "will be positive" increased (P<0.05). Additionally, most mothers thought that "Although the smart device is currently unnecessary, it will be needed in future" in 2017 (46.3%). Conclusion: Limiting the smart device usage time during the weekends and increasing parental involvements are recommended. Guidelines for smart devices usage in young children are also necessary considering the changes in parental attitudes in recognizing the smart device usage as unavoidable.

Dosimetric comparison for Prostate VMAT of weight and photon energy change (전립선 암 입체적세기변조방사선치료 시 체형 및 에너지 변화에 따른 선량 평가)

  • Jo, Guang Sub;Kim, Min Woo;Baek, Min Gyu;Chae, Jong Pyo;Ha, Se Min;Lee, Sang Bong
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.17-25
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    • 2018
  • Purpose : To compare the radiation doses of prostate cancer patients according to changes in abdominal body shape and energy during Volumetric modulated arc therapy(VMAT). Materials and Methods : Seven patients with prostate cancer were enrolled in this study. VMAT treatment plan was established at 6, 10, and 15 MV while changing from -2.0 cm to 2 cm by 0.5 cm. Conformal index(CI), homogeneous index(HI), $D_{max}$, $D_{95%}$, $D_{50%}$ and $D_{2%}$ of PTV were examined in order to evaluate the change of dose in the target organ according to body shape change. Normal organ of the femoral head, rectum and bladder was analyzed to evaluate dose changes. Results : The dose of $D_{max}$ 6 MV in PTV increased to 107.2 % in 1.0 cm body shape reduction, and 10 MV and 15 MV dose increased to 107.1 % and 107.0 % in 1.5 cm body reduction, respectively. The dose of $D_{50%}$ 6 MV in PTV decreased to 99.64 % in 1.0 cm body shape increase, and in 10 MV and 15 MV dose decreased to 99.79 % and 99.97 % in 1.5 cm body increase, respectively. In 2.0 cm body type increase, the dose was decreased to 99.30 % and 99.52 %, respectively. Doses for rectum and bladder gradually increased with decreasing weight, and dose decreased with decreasing weight. 6 MV, and $V_{70Gy}$ at 10 MV increased from 11.50 % to 12.76 % when the external shape decreased by 2.0 cm. The bladder $V_{70Gy}$ also increased from 14.0 % to 15.2 %. It was also shown that the dose increased as the body weight decreased in the femoral head. Conclusion : In the treatment of VMAT, dose distribution can be changed according to the change of abdominal shape. SSD and CBCT were used to decrease the body shape by more than 1cm or more than 1.0 cm at 6 MV and the body shape by more than 1.5 cm or more than 1.5 cm at 10 MV or 15 MV. It is considered that a new treatment plan should be established through re-simulation.

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