• Title/Summary/Keyword: Radiation field Size

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Efficacy and Accuracy of Patient Specific Customize Bolus Using a 3-Dimensional Printer for Electron Beam Therapy (전자선 빔 치료 시 삼차원프린터를 이용하여 제작한 환자맞춤형 볼루스의 유용성 및 선량 정확도 평가)

  • Choi, Woo Keun;Chun, Jun Chul;Ju, Sang Gyu;Min, Byung Jun;Park, Su Yeon;Nam, Hee Rim;Hong, Chae-Seon;Kim, MinKyu;Koo, Bum Yong;Lim, Do Hoon
    • Progress in Medical Physics
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    • v.27 no.2
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    • pp.64-71
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    • 2016
  • We develop a manufacture procedure for the production of a patient specific customized bolus (PSCB) using a 3D printer (3DP). The dosimetric accuracy of the 3D-PSCB is evaluated for electron beam therapy. In order to cover the required planning target volume (PTV), we select the proper electron beam energy and the field size through initial dose calculation using a treatment planning system. The PSCB is delineated based on the initial dose distribution. The dose calculation is repeated after applying the PSCB. We iteratively fine-tune the PSCB shape until the plan quality is sufficient to meet the required clinical criteria. Then the contour data of the PSCB is transferred to an in-house conversion software through the DICOMRT protocol. This contour data is converted into the 3DP data format, STereoLithography data format and then printed using a 3DP. Two virtual patients, having concave and convex shapes, were generated with a virtual PTV and an organ at risk (OAR). Then, two corresponding electron treatment plans with and without a PSCB were generated to evaluate the dosimetric effect of the PSCB. The dosimetric characteristics and dose volume histograms for the PTV and OAR are compared in both plans. Film dosimetry is performed to verify the dosimetric accuracy of the 3D-PSCB. The calculated planar dose distribution is compared to that measured using film dosimetry taken from the beam central axis. We compare the percent depth dose curve and gamma analysis (the dose difference is 3%, and the distance to agreement is 3 mm) results. No significant difference in the PTV dose is observed in the plan with the PSCB compared to that without the PSCB. The maximum, minimum, and mean doses of the OAR in the plan with the PSCB were significantly reduced by 9.7%, 36.6%, and 28.3%, respectively, compared to those in the plan without the PSCB. By applying the PSCB, the OAR volumes receiving 90% and 80% of the prescribed dose were reduced from $14.40cm^3$ to $0.1cm^3$ and from $42.6cm^3$ to $3.7cm^3$, respectively, in comparison to that without using the PSCB. The gamma pass rates of the concave and convex plans were 95% and 98%, respectively. A new procedure of the fabrication of a PSCB is developed using a 3DP. We confirm the usefulness and dosimetric accuracy of the 3D-PSCB for the clinical use. Thus, rapidly advancing 3DP technology is able to ease and expand clinical implementation of the PSCB.

The Development and Evaluation of Web-based Education Program for Lung Cancer Patient (폐암환자를 위한 웹기반 교육프로그램 개발 및 평가)

  • Yoo, Han-Jin
    • Asian Oncology Nursing
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    • v.5 no.1
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    • pp.11-21
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    • 2005
  • The purpose of this study were to develop an web-based education program for Lung cancer patients and to test its effects on patients' self-care knowledge, compliance to medical regimen, nutrition status and pain. The program was developed by the following process: first, Lung cancer patients demand on the web-based program was investigated. and second, the program was developed with the help of various reference books and then validation of experts group. last, educations effects on the patients is evaluated and compared the differences in self-care knowledge, compliance to medical regimen, nutrition status and pain between on experimental group and a control group on before discharge 1day and 3weeks after. SPSS/Win 11.0 program was used for data analysis. It was proven with $x^2$ test and t-test, and Pearson Correlation coefficient, and Chronbach's alpha coefficient were done for the reliability of measuring instruments. 1. The summary of the Program development is as follows. The program is based on patients' questionnaire and reference material and is made for users friendly. Not only Bigger font size and bright colors but also illustrations or pictures were adopted to help enhance patients' understanding. 2. The summary of the study results is as follows. 1) Compared with control group, the web-based educated experimental group showed a statistical significant difference on self-care knowledge, Especially disease, radiation treatment, medication & analgesics, chemotherapy side effect, but there was no significant difference in the field of chemotherapy, in the fields of operation, diet & general knowledge. 2) Compared with control group, the web-based educated experimental group showed a statistical significant difference on compliance to medical regimen, especially in the field of follow up care, everyday life, diet, but there was no significant difference in the field of medication, exercise. 3) Compared with control group, web-based educated experimental group showed no significant difference in nutrition status, but partially significant difference in body weight. 4) Compared with control group, the web-based educated experimental group showed no significant difference in pain level. 5) The significantly positive correalation self-care knowledge with the compliance to medical regimen. 6) Users satisfaction with the web-based education program of the contents quality, the level of recommendation to others, content layout, medical information quality, but interesting got a low mark.

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Characteristics of the soil loss and soil salinity of upland soil in saemangeum reclaimed land in western South Korea

  • Kim, Young Joo;Lee, Su Hwan;Ryu, Jin Hee;Oh, Yang Yeol;Lee, Jeong Tae
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.316-316
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    • 2017
  • The objective of this study is to estimate quantitatively soil salinity and soil loss at upland soils in agriculture land region in Saemangeum reclaimed land on the south Korea coasts. Soil loss and soil salinity are the most critical problem at reclaimed tidal saline soil in Korea. The several thematic maps of research area such as land cover map, topographic and soil maps, together with tabular precipitation data used for soil erosion and soil salinity calculation. Meteorological data were measured directly as air temperature, wind speed, solar radiation, and precipitation. The experiment was conducted 2% sloped lysimeter ($5.0m{\times}20.0m$) with 14 treatments and it were separated by low salinity division (LSD) and high salinity division (HSD) install. The cation content in ground water increased during time course, but in the case of land surface water the content was variable, and $K^+$ was lower than that of $Na^+$ and $Mg^{2+}$. At the LSD under rainproof condition, the salinity was directly proportional to soil water content, but at the HSD the tendency was no reversed. In condition of rainproof, the amount of soil salinity was higher at the HSD than at the LSD. Positive correlation was obtained between the soil water content and available phosphorous content at the rainfall division, but there was no significance at the surface soil of the rainproof division. Sodium adsorption ratio and anion contents in soil were repressed in the order of vinyl-mulching > non-mulching > bare field. According to the result of analyzing soil loss, soil loss occurred in a vinyl-mulching, a non-mulching and a bare field in size order, and also approximately 11.2 ton/ha soil loss happened on the reclaimed land area. The average soil loss amount by the unit area takes place in a non-mulching and bare field a lot. Our results indicate that soluble salt control and soil erosion are critical at reclaimed tidal saline soil and the results can provide some useful information for deciding management plans to reduce soil loss and salt damage for stable crop production and diverse utilization or cultivation could be one of the management options to alleviate salt damage at reclaimed tidal saline soil in Korea.

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The study of thermal change by chemoport in radiofrequency hyperthermia (고주파 온열치료시 케모포트의 열적 변화 연구)

  • Lee, seung hoon;Lee, sun young;Gim, yang soo;Kwak, Keun tak;Yang, myung sik;Cha, seok yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.27 no.2
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    • pp.97-106
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    • 2015
  • Purpose : This study evaluate the thermal changes caused by use of the chemoport for drug administration and blood sampling during radiofrequency hyperthermia. Materials and Methods : 20cm size of the electrode radio frequency hyperthermia (EHY-2000, Oncotherm KFT, Hungary) was used. The materials of the chemoport in our hospital from currently being used therapy are plastics, metal-containing epoxy and titanium that were made of the diameter 20 cm, height 20 cm insertion of the self-made cylindrical Agar phantom to measure the temperature. Thermoscope(TM-100, Oncotherm Kft, Hungary) and Sim4Life (Ver2.0, Zurich, Switzerland) was compared to the actual measured temperature. Each of the electrode measurement position is the central axis and the central axis side 1.5 cm, 0 cm(surface), 0.5 cm, 1.8 cm, 2.8 cm in depth was respectively measured. The measured temperature is $24.5{\sim}25.5^{\circ}C$, humidity is 30% ~ 32%. In five-minute intervals to measure the output power of 100W, 60 min. Results : In the electrode central axis 2.8 cm depth, the maximum temperature of the case with the unused of the chemoport, plastic, epoxy and titanium were respectively $39.51^{\circ}C$, $39.11^{\circ}C$, $38.81^{\circ}C$, $40.64^{\circ}C$, simulated experimental data were $42.20^{\circ}C$, $41.50^{\circ}C$, $40.70^{\circ}C$, $42.50^{\circ}C$. And in the central axis electrode side 1.5 cm depth 2.8 cm, mesured data were $39.37^{\circ}C$, $39.32^{\circ}C$, $39.20^{\circ}C$, $39.46^{\circ}C$, the simulated experimental data were $42.00^{\circ}C$, $41.80^{\circ}C$, $41.20^{\circ}C$, $42.30^{\circ}C$. Conclusion : The thermal variations were caused by radiofrequency electromagnetic field surrounding the chemoport showed lower than in the case of unused in non-conductive plastic material and epoxy material, the titanum chemoport that made of conductor materials showed a slight differences. This is due to the metal contents in the chemoport and the geometry of the chemoport. And because it uses a low radio frequency bandwidth of the used equipment. That is, although use of the chemoport in this study do not significantly affect the surrounding tissue. That is, because the thermal change is insignificant, it is suggested that the hazard of the chemoport used in this study doesn't need to be considered.

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Studies on Size and Weight of Pupae of Laboratory Reared Stable Flies (Stomoxys calcitrans) (인공사육한 침파리(Stomoxys calcitrans)용의 체장 및 체중에 관한 연구)

  • Chung K.H.
    • Korean journal of applied entomology
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    • v.22 no.3 s.56
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    • pp.228-231
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    • 1983
  • In order to eradicate harmful insect by use of sterile male techniques, it is necessary to disperse about 10 times as many male insect as in wild condition. However, it is so difficult to discriminate male insect in pupal stage that usually the population are likely to be contaminated by female insect when that are released in field. The present study was conducted to establish a useful method capable of differenciating the male pupae of Stomawys calcitsans by means of measuring the pupal weight and length. The results were summarized as follows; 1. Male pupa was lighter and shorter than female and high correlation existed between length and width of pupa. 2. There was significant relationship between the length of pupa and width of adult 3. When the pupal sex of stable ay was identified by median of mean length and mean weight of the pupae, the Ratio of female to male was 1 : 1. 4 and 1 : 2. 2, respectively. Therefore, median of pupal weight seemed to be applicable for obtaining more number of male pupae.

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Design of a Tag Antenna with a Low Performance Distortion from an Attached Surface Material Using the Asymmetric Dual-Arm Dipole Structure (부착면 표면물질에 의한 성능 왜곡을 최소화한 이중 선로의 비대칭 다이폴 형태 태그 안테나 설계)

  • Kim, Do-Kyun;Choo, Ho-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.4 s.119
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    • pp.398-407
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    • 2007
  • In this paper we proposed the tag antenna with a low performance distortion from an attached surface material using the asymmetric dual-arm dipole antenna(ADDA) structure. The tag is designed to exhibit low performance changes when the tag is attached on a target object(the medical litter receptacle, ${\varepsilon}_r=1.7,\;tan\;{\delta}=0.002$). Detail design parameters for the proposed antenna are optimized to maintain a good readable range in free-space as well as on a target object. The size of the optimized antenna is $100\;mm{\times}50\;mm$. The antenna shows the matching bandwidth($S_{11}$< -10 dB) of 3.7 % and the radiation efficiency of 80 % at the operating frequency. Finally we confirmed the readable range of the tag antenna by measurement and it shows about 5.3 m in free space and 5.5 m on the target object.

Design of Dual Reflector for Monopulse antennas System (모노펄스안테나 시스템에 적용되는 2중 반사경 설계)

  • Kim, Won-Sub
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.1
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    • pp.85-90
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    • 2008
  • In this paper, we studied on dual reflector adjusted to monopulse antenna system. As a result, when the efficiency of main reflector is more than 70%, The size of reflector is 30 wavelength of maximum frequency and minimum frequency gain is 37.9dBi, and Maximum frequency gain is 38.6dBi. Also, when a radius is D and Focus-distance is $F_e$, a scheme for efficiency improvement of Sub Reflector is to increase the Focus-distance to Diameter Ratio. In this case, Cross polarization in Far field improved and spherical spreading loss in circumference of reflector reduced. The influence of Radiation pattern followed by the side displacement of feed antenna(at $x_sy_s$) is decreased, it is confirmed that performance of scanning is improved.

AN ELECTRON MICROSCOPIC STUDY ON THE EFFECTS OF IRRADIATION ON THE ACINAR CELLS OF RAT PAROTID GLAND (방사선조사가 백서 이하선의 선세포에 미치는 영향에 관한 전자현미경적 연구)

  • Ko Kwang Jun;Lee Sang Rae
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.18 no.1
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    • pp.31-45
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    • 1988
  • The author studied the histopathologic changes according to a single or a split dose and the time after irradiation on the acinar cells of rat parotid gland. 99 Sprague Dawley rats, weighing about l20gm, were divided into control and 3 experimental groups. In experimental groups, GroupⅠ and Ⅱ were delivered a single dose of l5Gy, 18Gy and Group Ⅲ and Ⅳ were delivered two equal split doses of 9Gy, 10.5Gy for a 4 hours interval, respectively. The experimental groups were delivered by a cobalt-60 teletherapy unit with a dose rate of 222cGy/min, source-skin distance of 50㎝, depth of l㎝ and a field size of l2×5㎝. The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and examined by light and electron microscopy. The results were as follows: 1. As the radiation dose increased and the acinar cells delivered a single dose exposure were more damaged, and the change of acinar cells appeared faster than those of a split dose exposure. 2. The histopathologic change of acinar cells appeared at 1 hour after irradiation. The recovery from damaged acinar cells appeared at 1 day after irradiation and there was a tendency that the recovery from damage of a split dose exposure was somewhat later than that of a single dose exposure. 3. Light microscope showed atrophic change of acinar cells and nucleus, degeneration and vesicle formation of cytoplasm, widening of intercellular space and interlobular space. 4. Electron microscope showed loss of nuclear membrane, degeneration of nucleus and nucleoli, clumping of cytoplasm, widening and degeneration of rough endoplasmic reticulum, loss of cristae of mitochondria, lysosome, autophagosome and lipid droplet. 5. Electron microscopically, the change of rough endoplasmic reticulum was the most prominent and this appeared at 1 hour after irradiation as early changes of acinar cells. The nuclear change appeared at 2 hours after irradiation and the loss of cristae of mitochondria was observed at 2 hours after irradiation in all experimental groups.

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Design of Gate Driver Chip for Ionizer Modules with Fault Detection Function (Fault Detection 기능을 갖는 이오나이저 모듈용 게이트 구동 칩 설계)

  • Jin, Hongzhou;Ha, PanBong;Kim, YoungHee
    • Journal of IKEEE
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    • v.24 no.1
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    • pp.132-139
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    • 2020
  • The ionizer module used in this air cleaner supplies high voltages of 3.5KV / -4KV to the discharge electrode HV+ / HV- using a winding transformer to generate positive and negative ions by electric field radiation of carbon fiber brush. The ionizer module circuit using the existing MCU has the disadvantage of large PCB size and expensive price, and the gate driver chip using the existing ring oscillator has oscillation period sensitive to PVT (Process-Voltage-Temperature) fluctuation and there is risk of fire or electric shock because there is no fault detection function by short circuit of HV+ and GND as well as HV- and GND. Therefore, in this paper, even though PVT fluctuates, by using 7-bit binary up counter, HV+ voltage reaches the target voltage by adjusting oscillation period. And an HV+ short fault detection circuit for detecting a short circuit between HV+ and GND, an HV- short fault detection circuit for detecting a short circuit between HV- and GND, and an OVP (Over-Voltage Protection) for detecting that HV+ rises above an overvoltage are newly proposed.

The Case Report of Malignant Lymphoma on the Submandibular Gland (턱밑샘에 발생한 악성 림프종의 치험례)

  • Bea, Chung Sang;Lee, Nae Ho;Yang, Kyung Moo
    • Archives of Plastic Surgery
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    • v.34 no.2
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    • pp.261-264
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    • 2007
  • Purpose: Extranodal marginal zone B cell lymphoma of MALT type represents approximately 8% of non-Hodgkin's lymphomas and this lymphoma is present in extranodal sites. Although the presentation of this lymphomain in stomach is usually associated with H. pylori infection in 95% of cases, MALT lymphoma found in soft tissue has been reported very rarely in the field of plastic surgery. We report a case of MALT lymphoma in the submandibular gland without any involvement of other organs such as the stomach. Methods: A 49-year-old man complained of a huge neck mass sized about $10{\times}12cm$. It started about 2 years ago and grew rapidly for the late 6 months. It was of hard nature with erythematous skin overlying it. Under the diagnosis of possible malignant lymphoma or sarcoma, radical resection was performed and the defect was reconstructed using transverse rectus abdominis musculocutaneous free flap. Results: The mass was well demarcated from the normal tissue, $11{\times}10.5{\times}10cm$ in size and whitish-gray color. Immunohistochemical analysis demonstrated that the tumor cells were LCA(+), CD20(+), CD3(-) and CD5(-). The tumor was diagnosed as extranodal marginal zone B cell lymphoma. The patient was treated with prophylactic radiation therapy after surgery, there was no complication for 1 year. Conclusion: We reported that very rare form of MALT lymphoma in 49-year-old male patient was experienced with clinical characteristics, histologic features and references.