• Title/Summary/Keyword: clinical application

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Clinicopathologic Evaluation of Gastric Polyps Remainding in the Stomach after a Gastrectomy (위 절제술 후 발생한 위 폴립의 임상 병리학적 특징)

  • Yoon, Ki-Young;Cho, Sung-Jin;Kim, Jeong-Hon;Kim, Young-Sik;Lee, Sang-Ho
    • Journal of Gastric Cancer
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    • v.5 no.3 s.19
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    • pp.169-173
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    • 2005
  • Background: Gastric polyps encompass a wide variety of lesions that most commonly arise from the gastric epithelium. However, coincidental gastric carcinomas have rarely been reported, being found in $1.5{\sim}2.1%$ of patients with hyperplastic polyps. The sizes and the pathologies of polyps seem to be important in the application of treatment. Therefore, it is necessary to classily gastric polypoid lesions after a gastrectomy. Materials and Methods: During a follow-up endoscopy study, 23 patients were found to have developed gastric polyps after a gastrectomy. Most of those polyps were removed by using an endoscopic polypectomy. We performed clinical and pathologic evaluations of the gastric polyps in the remainding in the stomach after a gastrectomy, Results: The mean age of the patients was 64.5 years old with the incidence of polyps remainding in the stomach after a gastrectomy increasing after the first year following the gastrectomy. The sizes of the polyps ranged from 0.3cm to 3.5cm in diameter and the numbers of polyps below 1.0cm were 19 (82.6%). The anastomotic site was the most prevalent place 10 (43.2%), followed by the cardia 6 (26.0%) and the body 4 (17.3%). Among 23 gastric polypoid lesions Yamada types of gastric polyps in the remainding in the stomach were as follows: 1 case in type I, 12 cases in type II, 9 cases in type III, 1 case in type IV. The pathologic diagnoses of the polyps were hyperplastic polyps in 6 cases, tubular adenomas in 2 cases and inflammatory polyps in 15 cases. Conclusion: Endoscopic polypectomy is believed to be important in assessing the precise diagnosis of gastric polyps remainding in the stomach. In this study, hyperplastic polyps were found to have no malignant potential, despite their sizes. As a result aggressive biopsy with a polypectomy of gastric polyp afier gastrectomy is recommended and frequent follow-up be performed.

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An Evaluation of the Accuracy of Mini-Wright Peak Flow Meter (mini-Wright Peak Flow Meter에 의한 PEFR 측정의 정확도)

  • Koh, Young-Il;Choi, In-Seon;Na, Hyun-Ju;Park, Seok-Chae;Jang, An-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.2
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    • pp.298-308
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    • 1997
  • Background : Portable devices for measuring peak expiratory flow(PEF) are now of proved value in the diagnosis and management of asthma and many lightweight PEF meters have become available. However, it is necessary to determine whether peak expiratory flow rate(PEFR) measurements measured with peak flowmeters is accurate and reproducible for clinical application. The aim of the present study is to define accuracy, agreement, and precision of mini-Wright peak flow meter(MPFM) against standard pneumotachygraph. Methods : The lung function tests by standard pneumotachygraph and PEFR measurement by MPFM were performed in a random order for 2 hours in 22 normal and 17 asthmatic subjects and also were performed for 3 successive days in 22 normals. Results : The PEFR measured with MPFM was significantly related to the PEFR and $FEV_1$ measured with standard pneumotachygraph in normal and asthmatics(for PEFR, r = 0.92 ; p < 0.001 ; for $FEV_1$, r = 0.78 ; p < 0.001). The accuracy of MPFM was within 100(limits of accuracy recommeded by NAEP) in all the subjects or 22 normal, mean difference from standard pneumotachygraph being 16.5L/min(percentage of difference being 2.90%) or 10.6L/min(percentage of difference being 1.75%), respectively. According to the method proposed by Bland and Altman, the 95% limits of the distribution of differences between MPFM and standard pneumotachygraph after correction of PEFR using our regression equation were +38.2 and -71.5L/min in all the subjects or 20.49~+9.49L/min in 22 normal and was similar to the intraindividual agreements for 3 successive days in normal. There was no statistically significant difference of PEFR measured with MPFM and standard pneumotachygraph among three days(p > 0.05) and the coefficient of variation($2.4{\pm}1.2%$) of PEFR measured with MPFM was significantly lower than that($5.2{\pm}3.5%$) with standard pneumotachygraph in normal (p < 0.05). Conclusion : This results suggest that the MPFM was as accurate and reproducible as standard pneumotachygraph for monitoring of PEFR in the asthmatic subjects.

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Analysis of Bone Marrow Micrometastasis Using RT-PCR in Patients with Small Cell Lung Carcinoma (소세포 폐암에서 역전사 중합효소 연쇄반응(RT-PCR)을 이용한 골수 미세전이(naicronaetastasis)의 분석)

  • Kim, Tae-You;Park, Jong-Kook;Ryoo, Baek-Ryeol;Im, Yung-Hyuck;Kang, Yoon-Koo
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.6
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    • pp.797-806
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    • 1999
  • Background: About 20% of small cell lung cancer(SCLC) patients have bone marrow(EM) metastasis at the time of diagnosis and the remaining patients are also considered with micrometastasis. In an attempt to detect EM micrometastasis, we used cytokeratin(CK)-20 as a molecular marker, which is specific for epithelial cells. Method: A sensitive RT-PCR assay was used to compare CK-20 expression both in SCLC cell line H209 and normal leukocyte and to evaluate EM aspirates of 28 SCLC patients. Result: H209 cell line showed CK-20 expression but normal leukocyte did not, suggesting CK-20 expression is lung tissue-specific. Of 28 patients(11 limited disease, 17 extensive disease), only 2(1/11, 1/17) samples tested revealed positive signal for CK-20. Two patients with CK-20 expression had EM metastasis or multiple bone involvement during follow-up. Conclusion: Although circulating tumor cells were detected in EM of small portion of patients with bone metastasis, CK-20 doesn't seem to be a reliable marker for the detection of micrometastasis in SCLC. This study emphasizes that identification of more specific marker for micrometastsis is mandatory prior to clinical application.

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Effects of Coculture on Development of Biopsied Mouse Embryos as a Preclinical Model for Preimplantation Genetic Diagnosis of Human Embryos (생쥐 모델을 이용한 배아의 할구 생검법과 할구가 생검된 배아의 배양시 공배양 효과에 관한 연구: 인간에서의 착상 전 유전진단 기술 개발을 위한 동물실험 모델의 개발)

  • Kim, S.H.;Ryu, B.Y.;Jee, B.C.;Choi, S.M.;Kim, H.S.;Pang, M.G.;Oh, S.K.;Suh, C.S.;Choi, Y.M.;Kim, J.G.;Moon, S.Y.;Lee, J.Y.;Chae, H.D.;Kim, C.H.
    • Clinical and Experimental Reproductive Medicine
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    • v.26 no.1
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    • pp.9-20
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    • 1999
  • The genetic defects in human gametes and embryos can cause adverse effects on overall reproductive events. Biopsy of embryos for preimplantation genetic diagnosis (PGD) offers a new possibility of having children free of the genetic disease. In addition, advanced embryo culture method may enhance the effectiveness of embryo biopsy for the practical application of PGD. This experimental study was undertaken to evaluate the effects of coculture on the development in vitro of biopsied mouse embryos as a preclinical model for PGD of human embryos. Embryos were obtained after in vitro fertilization (IVF) from F1 hybrid mice (C57BLfemale/CBAmale). Using micromanipulation, 1, 2, 3 or 4 blastomeres of 8-cell stage embryos were aspirated through a hole made in the zona pellucida by zona drilling (ZD) with acidic Tyrode's solution (ATS). After biopsy of blastomeres, embryos were cultured in vitro for 110 hours in Ham's F-10 supplemented with 0.4% BSA or cocultured on the monolayer of Vero cells in the same medium. The frequence of blastocyst formation were recorded, and the embryos beyond blastocyst stage were stained with 10% Giemsa to count the total number of nuclei in each embryo. There was no significant difference in the blastocyst formation between the zona intact control group and the zona drilling (ZD) only, or biopsied groups. The hatching rate of all the treatment groups except 4/8 group was significantly higher than that of control group. In all the treatment groups, there was a significant reduction in the mean cell number of embryos beyond blastocyst stage ($50.2{\pm}14.0$ in control group vs. $41.2{\pm}7.9$ in ZD, $39.3{\pm}8.8$ in 7/8, $29.7{\pm}6.4$ in 6/8, $25.1{\pm}5.7$ in 5/8, and $22.1{\pm}4.3$ in 4/8 groups, p<0.05). When the same treatments were followed by coculture with Vero cells, a similar pattern was seen in the blastocyst formation and the hatching rate. However, in all the treatment groups, there was a significant increase in the mean cell number of embryos beyond blastocyst stage with coculture, compared with the parallel groups without coculture. In the cleavage rate of biopsied blastomeres cultured for 110 hours after IVF, there was no significant difference between coculture and non-coculture groups (87.2% vs. 78.7%). However, the mean cell number of embryos developed from the biopsied blastomeres was significantly higher in coculture group ($11.5{\pm}4.7\;vs.\;5.9{\pm}1.9$, p<0.05). In conclusion, biopsy of mouse embryos after ZD with ATS is a safe and highly efficient method for PGD, and coculture with Vero cells showed a positive effect on the development in vitro of biopsied mouse embryos and blastomeres as a preclinical model for PGD of human embryos.

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GRO-${\alpha}$, IL-8 and ENA-78 : Expressed by Stimulated Endothelial Cells and Increased PMN Adhesion (활성화된 내피세포에서 GRO-${\alpha}$, IL-8 및 ENA-78의 발현양상과 호중구 부착에 미치는 영향)

  • Ryu, Ki-Chan;Kim, Yun-Seong;Kim, Yong-Ki;Kim, In-Ju;Kim, Young-Dae;Lee, Chang-Hun;Park, Do-Youn;Kim, Ji-Yeon;Ha, Tae-Jeong;Lee, Min-Ki;Park, Soon-Kew
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.2
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    • pp.145-155
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    • 2002
  • Background: Inflammation, where vascular endothelial cells are activated by cytokines, recruits circulating leukocytes such as neutrophils into the tissues. Mononuclear phagocytes as well as tissue cells activated by these stimuli produce these chemokines. In this study, thr effects of IL-1 and LPS on the expression of CXC chemokines such as GRO-${\alpha}$, IL-8 and ENA-78 in vascular endothelial cells and the neutrophil adhesion effects of ENA-78 and GRO-${\alpha}$ was investigated. Methods: Human umbilical vein endothelial cells were cultured and stimulated with various concentrations of IL-1 and LPS. The concentrations of the GRO-${\alpha}$, IL-8 and ENA-78 secreted were measured using enzymelinked immunosorbent assay. The effects of ENA-78 and GRO-${\alpha}$ on neutrophil adhesion to the endothelial cells were also investigated. Results: The addition of IL-1 and LPS to the vascular endothelial cells induced GRO-${\alpha}$ IL-8 and ENA-78 secretion in a time- and dose-dependent manner. The neutrophil adhesion was also increased by induction of ENA-78 and GRO-${\alpha}$ to the vascular endothelial cells in a dose-dependent manner. Conclusion: CXC chemokines such as GRO-${\alpha}$, IL-8 and ENA-78 secreted by the vascular endothelial cells play an important role in the acute inflammatory responses by stimulating neutrophil adhesion to the vascular endothelial cells, raising the possibility that the CXC chemokines are one of the targets in the clinical application of acute inflammation.

Deviations of Implant Position between Pre- and Post-operation in Computer-guided Template-based Implant Placement (Computer-guided template를 이용한 임플란트 식립에서 술 전과 술 후 사이의 임플란트 위치에 따른 변위량 검사)

  • Kim, Won;Kim, Seung-Mi;Kim, Hyo-Jung;Song, Eun-Young;Lee, Si-Ho;Oh, Nam-Sik
    • Journal of Dental Rehabilitation and Applied Science
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    • v.27 no.2
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    • pp.175-184
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    • 2011
  • With a development of implant restoration technique, there are increasing use of computer-guided system for edentulous patients. It was carried out simulated operation based on CT information about patient's bone quantity, quality and anatomical landmark. However, there are some difference between the programmed implant and post-operative implant about it's position. If the deviation was severe, it could happen a failure of 'passive fit' and not suited for path of implant restoration. The aim of this presentation is to evaluate about a degree of deviations between programmed implant and post-operative implant. Five patients treated by 'NobelGuide' system (Nobel Biocare AB, G$\ddot{o}$teborg, Sweden) in Department of Prosthodontics, Inha University were included in this study. The patients were performed CT radiograph taking and intra-oral impression taking at pre-operation. Based on CT images and study model, surgical stent was produced by NobelBiocareTM. To fabricated a pre-operative study model, after connected lab analog to surgical template, accomplished a pre-operative model using type 4 dental stone. At final impression, a post-operative study model was fabricated in the conventional procedures. Each study model was performed CT radiograph taking. Based on CT images, each implant was simulated in three dimensional position using $Procera^{(R)}$ software (Procera Software Clinical Design Premium, version 1.5; Nobel Biocare AB). In 3D simulated model, length and angulation between each implant of both pre- and post-operative implants were measured and recorded about linear and angular deviation between pre-and post-operative implants. A total of 24 implants were included in this study and 58 inter-implant sites between each implant were measured about linear and angular deviations. In the linear deviation a mean deviation of 0.41 mm (range 0~1.7 mm) was reported. In the angular deviation, a mean deviation was $1.99^{\circ}$ (range $0^{\circ}{\sim}6.7^{\circ}$). It appears that the both linear and angular mean deviation value were well acceptable to application of computer-guided implant system.

Study on the Anti-oxydative, Anti-tumor effect of Whakijogyungtang (화기조경탕(化氣調經湯)이 항산화 및 항암효과)

  • Yu, Mi-Kyung;Kim, Jong-Han;Park, Su-Yeon;Choi, Jeong-Hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.20 no.1 s.32
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    • pp.80-98
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    • 2007
  • Objectives : This study was carried out to evaluate anti-oxydative, anti-tumor effect for clinical application of Whakijogyungtang (WJT) Results : 1. DPPH radical scavenging activities of WJT water extracts(Exts) were in proportion as concentration of WJT.(3 ${\mu}g/ml:12.6{\pm}2.3$ %) 2. ABTS+ scavenging activities of WJT water Exts were more effective in high density.(3 ${\mu}g/ml:4.3{\pm}1.6$ %, 10 ${\mu}g/ml$: $11.8{\pm}2.5$ %, 30 ${\mu}g/ml:45.3{\pm}3.2%$ 100 ${\mu}g/ml$: $62.7{\pm}4.8%$) 3. Hydrogen peroxide$(H_2O_2)$ scavenging activities of WJT water Exts were effective.(3 ${\mu}g/ml:4.7{\pm}0.8$ %, 10 ${\mu}g/ml: $8.2{\pm}1.6$ %, 30 ${\mu}g/ml:19.5{\pm}3.2$ % 100 ${\mu}g/ml$: $24.6{\pm}3.8$ %) 4. Anti oxidative effects against linoleic acid were not effective. 5. The generation of $O_2\;^-$ in S-180 cells were according to the concentration of WJT water Exts, specially effective over 100 ${\mu}g/ml$ concentration. 6. The SOD activities in S-180 cells were in proportion as cytotoxicity against S-180 cells of WJT water Exts. 7. The GPx activities in S-180 cells were in proportion as cytotoxicity against S-180 cells of WJT water Exts(more effective on 300 ${\mu}g/ml$ and 1000 ${\mu}g/ml$ concentration), but the catalase activities in S-180 cells were not effective. 8. The results of activites against multi-drug-resistance(MDR) of WJT were as follows. 1) In water Exts from WJT, cytotoxicity against AML-2/D100 with vincristine($IC_{50:}39.78$ ${\mu}g/ml$) was more effective than without vincristine($IC_{50:}$ 183.58 ${\mu}g/ml$), Cross resistance(CR:3.85) was not effective, and anti-MDR activites(RF) was effective.(RF:3.85) 2) In hexane fraction, cytotoxicity against AML-2/D100 with vincristine ($IC_{50:}130.88$ ${\mu}g/ml$) was more effective than without vincristine ($IC_{50:}293.10$ ${\mu}g/ml$) and anti-MDR activites(RF) was effective.(RF:4.61) 3) In chloroform fraction, the cytotoxicity against AML-2/WT and AML-2/D100 was not effective. 4) In ethyl acetate fraction, cytotoxicity against AML-2/D100 with vincristine($IC_{50:}36.43$ ${\mu}g/ml$) was more effective than without vincristine ($IC_{50:}73.07$ ${\mu}g/ml$), Cross resistance(CR:0.53) was not effective, and anti-MDR activites(RF) was effective.(RF:2) 5) In butanol fraction, the cytotoxicity against AML-2/WT and AML-2/D100 was not effective. 6) In $H_2O$ fraction, the cytotoxicity against AML-2/WT and AML-2/D100 was not effective. Conclusion : These result suggest that WJT has antioxidative effects, anti-tumor effects by apoptosis of free radical$(O_2\;^-)$ activity, and anti-MDR activites(especially hexane and ethyl acetate fraction).

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A Systematic Review on the Effects of Virtual reality-based Telerehabilitation for Stroke Patients (뇌졸중 환자를 위한 가상현실 기반의 원격재활 효과에 관한 체계적 고찰)

  • Lim, Young-Myoung;Lee, ji-Yong;Jo, Seong-Jun;Ahn, Ye-Seul;Yoo, Doo-Han
    • The Journal of Korean society of community based occupational therapy
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    • v.7 no.1
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    • pp.59-70
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    • 2017
  • Objective : The purpose of this study was to examine the effect of virtual reality-based remote rehabilitation on stroke patients systematically and to look for its effect and how to apply it domestically. Methods : In order to search data, EMBASE and CINAHL database were used. Relevant research used those terms of virtual reality, telerehabilitation, and stroke. A total of 10 studies satisfying the selection criteria was analyzed according to their qualitative level, general characteristics, and PICO method. Results : Based on the selected 10 studies, virtual reality-based telerehabilitation system was applied. Sensory and motor feedback was provided with inputting visual and auditory senses through a video in the home environment, and it stimulated changes in the client's nervous system. Tools to measure the results were upper extremity function, balance and gait, activities of daily living, etc. Those virtual reality-based telerehabilitation method had an effect on upper extremity function and ability of sense of balance in all studies, and on the activities of daily living partially. Telerehabilitation service to make up environmental specificity improved satisfaction of client. That meaned the effect of the intervention to maintain the function. Conclusion : The virtual reality-based telerehabilitation system was applied to upper extremity function, sense of balance, and activities of daily living largely, and it showed that it helped to improve functions through intervention, supervision, and training of therapist in the home environment as well. This study suggests the basis and possibility of clinical application on virtual-reality based telerehabilitation. Additional research is needed to diverse virtual reality intervention methods and the effect of telerehabilitation in the future.

COLOR DIFFERENCES BETWEEN RESIN COMPOSITES BEFORE- AND AFTER-POLYMERIZATION, AND SHADE GUIDES (복합레진의 광중합 전·후와 shade guide의 색차 비교)

  • Chon, Yi-Ju;Cho, Sung-Shik;Um, Chung-Moon
    • Restorative Dentistry and Endodontics
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    • v.24 no.2
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    • pp.299-309
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    • 1999
  • The composite resin, due to its esthetic qualities, is considered the material of choice for restoration of anterior teeth. With respect to shade control, the direct-placement resin composites offer some distinct advantages over indirect restorative procedures. Visible-light-cured (VLC) composites allow dentists to match existing tooth shades or to create new shades and to evaluate them immediately at the time of restoration placement. Optimal intraoral color control can be achieved if optical changes occurring during application are minimized. An ideal VLC composite, then, would be one which is optically stable throughout the polymerization process. The shade guides of the resin composites are generally made of plastic, rather than the actual composite material, and do not accurately depict the true shade, translucency, or opacity of the resin composite after polymerization. So the numerous problems associated with these shade guides lead to varied and sometimes unpredictable results. The aim of this study was to assess the color changes of current resin composite restorative materials which occur as a result of the polymerization process and to compare the color differences between the shade guides provided with the products and the actual resin composites before- and after-polymerization. The results obtained from this investigation should provide the clinician with information which may aid in improved color match of esthetic restoration. Five light activated, resin-based materials (${\AE}$litefil, Amelogen Universal, Spectrum TPH VeridonFil-Photo, and Z100) and shade guides were used in this study. Three specimens of each material and shade combination were made. Each material was condensed inside a 1.5mm thick metal mold with 10mm diameter and pressed between glass plates. Each material was measured immediately before polymerization, and polymerized with Curing Light XL 3000 (3M Dental products, USA) visible light-activation unit for 60 seconds at each side. The specimens were then polished sequentially on wet sandpaper. Shade guides were ground with polishing stones and rubber points (Shofu) to a thickness of approximately 1.5mm. Color characteristics were performed with a spectrophotometer (CM-3500d, Minolta Co., LTD). A computer-controlled spectrophotometer was used to determine CIELAB coordinates ($L^*$, $a^*$ and $b^*$) of each specimen and shade guide. The CIELAB measurements made it possible to evaluate the amount of the color difference values (${\Delta}E{^*}ab$) of resin composites before the polymerization process and shade guides using the post-polishing color of the composite as a control, CIE standard D65 was used as the light source. The results were as follows. 1. Each of the resin composites evaluated showed significant color changes during light-curing process. All the resin composites evaluated except all the tested shades of 2100 showed unacceptable level of color changes (${\Delta}E{^*}ab$ greater than 3.3) between pre-polymerization and post-polishing state. 2. Color differences between most of the resin composites tested and their corresponding shade guides were acceptable but those between C2 shade of ${\AE}$litefil and IE shade of Amelogen Universal and their respective shade guides exceeded what is acceptable. 3. Comparison of the mean ${\Delta}E{^*}ab$ values of materials revealed that Z100 showed the least overall color change between pre-polymerization and post-polishing state followed by ${\AE}$litefil, VeridonFil-Photo, Spectrum TPH, and Amelogen Universal in the order of increasing change and Amelogen Universal. Spectrum TPH, 2100, VeridonFil-Photo and ${\AE}$litefil for the color differences between actual resin and shade guide. 4. In the clinical environment, the shade guide is the better choice than the shade of the actual resin before polymerization when matching colors. But, it is recommended that custom shade guides be made from resin material itself for better color matching.

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Comparing the dosimetric impact of fiducial marker according to density override method : Planning study (양성자 치료계획에서 fiducial marker의 density override 방법에 따른 선량변화 비교 : Planning study)

  • Sung, Doo Young;Park, Seyjoon;Park, Ji Hyun;Park, Yong Chul;Park, Hee Chul;Choi, Byoung Ki
    • The Journal of Korean Society for Radiation Therapy
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    • v.29 no.1
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    • pp.19-26
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    • 2017
  • Purpose: The application of density override is very important to minimize dose calculation errors by fiducial markers of metal material in proton treatment plan. However, density override with actual material of the fiducial marker could make problem such as inaccurate target contouring and compensator fabrication. Therefore, we perform density override with surrounding material instead of actual material and we intend to evaluate the usefulness of density override with surrounding material of the fiducial marker by analyzing the dose distribution according to the position, material of the fiducial marker and number of beams. Materials and Method: We supposed that the fiducial marker of gold, steel, titanium is located in 1.5, 2.5, 4.0, 6.0 cm from the proton beam's end of range using water phantom. Treatment plans were created by applying density override with the surrounding material and actual material of the fiducial marker. Also, a liver cancer patient who received proton therapy was selected. We located the fiducial marker of gold, steel, titanium in 0, 1.5, 3.5 cm from the proton beam's end of range and the treatment plans were created by same method with water phantom. Homogeneity Index(HI), Conformity Index(CI) and maximum dose of Organ At Risk(OAR) in Planning Target Volume(PTV) as the evaluation index were compared according to the material, position of the fiducial marker and number of beam. Results: The HI value was more decreased when density override with surrounding material of the fiducial marker was performed comparing with density override with actual material. Especially the HI value was increased when the fiducial marker was located farther from the proton beam's end of the range for a single beam and the fiducial marker's position was closer to isocenter for two or more beams. The CI value was close to 1 and OAR maximum dose was greatly reduced when density override with surrounding material of the fiducial marker was performed comparing with density override with actual material. Conclusion: Density override with surrounding material can be expected to achieve more precise proton therapy than density override with actual material of the fiducial marker and could increase the dose uniformity and target coverage and reduce the dose to surrounding normal tissues for the small fiducial markers used in clinical practice. Most of all, it is desirable to plan the treatment by avoiding the fiducial marker of metal material as much as possible. However, if the fiducial marker have on the beam path, density override of the surrounding material can be expected to achieve more precise proton therapy.

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