• Journal of Yeungnam Medical Science
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• 제17권2호
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• pp.123-128
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• 2000

본 연구에서 인체공학적으로 개선된 새로운 2-채널 고선량을 근접치료용 적용구(Shin's Applicator)를 개발하였으며, 기존의 단일 선원 근접치료 적용구와 비교하여 질벽에 더 균등한 방사선치료가 가능하고 방광과 직장선량이 적어 근접치료 후 발생할 수 있는 부작용이 감소될 가능성을 확인하였다. 임상적으로 Shin's Applicator는 자궁 경부암이나 자궁 체부암의 수술 후 국소재발이나, 절강에 발생한 다발설 악성종양을 효과적으로 치료하는 데 유용하게 사용될 수 있을 뿐 만 아니라, 방사선 치료 후 흔히 나타나는 질강의 협착을 예방할 수 있는 질 확장기(vaginal dilator)로도 사용 가능하였다. 이상의 결과에서 Shin's Applicator는 부인과 종양환자들의 방사선치료 뿐만 아니라 치료 후 삶의 질의 개선에도 크게 기여할 것으로 생각되었다.

• 대한방사선기술학회지:방사선기술과학
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• 제43권6호
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• pp.443-451
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• 2020

This study is to evaluate absorbed dose from right lung for brachytherapy and to estimate the effects of tissue heterogeneities on dose distribution for Iridium-192 source using Monte Carlo simulation. The study employed Geant4 code as Monte Carlo simulation to calculate the dosimetry parameters. The dose distribution of Iridium-192 source in solid water equivalent phantom including aluminium plate or steel plate inserted was calculated and compared with the measured dose by the ion chamber at various distances. And the simulation was used to evaluate the dose of gamma radiation absorbed in the lung organ and other organs around it. The dose distribution embedded in right lung was calculated due to the presence of heart, thymus, spine, stomach as well as left lung. The geometry of the human body was made up of adult male MIRD type of the computational human phantom. The dosimetric characteristics obtained for aluminium plate inserted were in good agreement with experimental results within 4%. The simulation results of steel plate inserted agreed well with a maximum difference 2.75%. Target organ considered to receive a dose of 100%, the surrounding organs were left the left lung of 3.93%, heart of 10.04%, thymus of 11.19%, spine of 12.64% and stomach of 0.95%. When the statistical error is performed for the computational human phantom, the statistical error of value is under 1%.

• Journal of Hospice and Palliative Care
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• 제11권3호
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• pp.136-139
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• 2008

목적: 경막외 모르핀 주입을 시행 받은 호스피스 병동의 암환자에서 통증 조절의 효율성과 안전성, 합병증에 대해 알아보고자 하였다. 방법: 2001년 3월부터 2004년 3월까지 3년간 성빈센트병원 호스피스 병동에 입원한 환자 중 경막외 모르핀 주입을 시행한 24명에 대해 환자의 일반 특성과 모르핀 등가용량, 기저 질환, 도관의 거치기간 등에 대해 후향 적으로 자료 분석하였다. 결과: 환자들은 위암, 췌장암이 각각 5명으로 가장 많았으며 경막외 모르핀 주입 부위는 흉추가 15명으로 가장 많았다. 시행 당시의 기저 모르핀 등가 용량(morphine equivalent daily dose, MEDD)은 615 mg이었다. 경막외 모르핀 주입을 시행 받고 1주일 뒤의 MEDD는 274 mg으로 효과적인 통증 조절이 가능하였다(P-value=0.000). 경막외 도관을 제거한 환자는 6명으로 이중 3명은 재 삽입하였다. 도관의 감염으로 인하여 제거한 환자는 2명이었다. 결론: 호스피스 병동에서 시행한 경막외 지속적 모르핀 주입은 진행한 암 환자의 통증 조절에 효율적이었으며 도관의 위치 변동, 감염으로 인하여 제거한 경우가 있었으나 조절 가능한 합병증이었다. 다만 1일 주사용 모르핀 요구량이 100 mg일 때 경막하 모르핀 주입법을 통한 통증 조절을 권하더라도 동의를 얻는데 걸리는 기간 중 기저 질환의 악화 등으로 인한 투여 모르핀 용량의 증량으로 경막외 모르핀 주입 당시 평균 MEDD는 615 mg이었다. 향후 환자 및 보호자들에게 경막외 모르핀 주입의 효율성과 안전성에 대한 정보 제공이 필요할 것으로 생각한다.

• 대한방사선기술학회지:방사선기술과학
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• 제41권2호
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• pp.135-140
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• 2018

In this study, the dose of antimony shielding sheet was measured and the shielding rates according to the distance between the radioisotopes and the detector was analyzed according to the type of $^{99m}Tc$, $^{18}F$, $^{201}Tl$, $^{131}I$, $^{123}I$ using the antimony shielding sheet. The detector was used with an inspector. Six sheets of 0.25 mmPb were prepared with 20 cm width and length. Measurement results using $^{99m}Tc$, $^{201}Tl$, and $^{123}I$ showed that as the thickness of the sheet became thicker, the farther the distance from the source to the sheet was, the smaller the transmitted dose amount was measured. It was analyzed that a thickness of 1.50 mm or more was required to obtain a shielding rates of 90% or more. In the experiments of $^{18}F$ and $^{131}I$, the dose value was highest when 0.25 mm sheet was used, and the shielding rates was negative, unlike the results of other radioisotopes. Since $^{201}Tl$ are used when using antimony sheet and $^{18}F$ and $^{131}I$ have no shielding effect, it is thought that it is effective to reduce dose by repeating training and simulation training so that work can be done in a short time.

• 한국소음진동공학회논문집
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• 제13권7호
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• pp.548-554
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• 2003

This study alms to investigate the dynamic properties of express buses in the very low frequencies which cause motion sickness Incidence. Since passengers often use express buses for long distance traveling. it is a critical point whether the ride give rise to motion sickness or not. In the study accelerations at the three Points on the floor of the six test vehicles were measured during the driving at constant speeds. By applying the frequency weighting corves suggested in ISO 26.31-1, the Physical quantity of accelerations were changed into the perceptual amount used to judge quantitatively the incidence of motion sickness. Motion sickness dose values were calculated from the frequency weighted time history of acceleration signals, and compared between the vehicles, driving conditions. and the seat positions in the bus. During the 50 minutes' driving on the public road and high ways. the vomiting incidence ratios were seen to range from 0.4 to 0.8 ％. which is equivalent to 2.4 to 4.8 ％ for 5 hours' driving. Unlike the very smooth road conditions considered in this work, motion sickness dose values encountered in real situations are expected to increase.

• 대한디지털의료영상학회논문지
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• 제13권2호
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• pp.71-76
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• 2011

Because interventional procedure operates looking at premier as real time when perate intervention enemy, by patient is revealed during suitableness time in radiation, side effect such as radiation injury of skin is apt to happen. It established by purpose of study that measure exposure dose that patient receives about these problem, and find solution for radiation injury and repletion method. In this study, we used Rando phantom of identical structure with the human body which becomes accomplished with 4 branch ingredient of the attempt and system equivalent material them and absorbed dose were measured by TLD. According to the laboratory, it shows that operations such as TFCA procedure or uterine myoma embolization are more dangerous than TACE procedure. If both operations are inspected during a short time, it is not affected in being bombed. However, it can lead to palliative agenesis or depilate, definitive agenesis only if operations are repeated more than three times. Dose distibution based on experiment, to reduce radiation exposure to patients result from reduction of scatter ray as we control field size of radiation and protection of side organs except for tumor. also we knew that we can protect patients form radiation exposure, if we increas SOD and decrease SID.

• 생물정신의학
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• 제5권2호
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• pp.263-277
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• 1998

Conventional high-dose antipsychotics tend to result in more side effects, negative symptoms and dysphoria, and at the same time lower the cognitive function which is already impaired in most schizophrenics. Florid psychotic symptoms, negative symptoms and cognitive impairment greatly impede psychosocial performance and eventual reintegration into society. The reduction of symptom and the improvement of cognitive funtions and social skills are therefore central to the psychiatric rehabilitation process. The purpose of this study was to evaluate the dose-reduction effects of antipsychotics on chronic schizophrenics prescribed conventional high-dose antipsychotics more than 1,500mg equivalent of chlorpromazine. Fifty-one chronic schizophrenics who maintained high-dose antipsychotics for more than three months were randomly assigned to two groups : 20 patients comprised the dose-maintaining group and 31 patients made the dose-reduction group. Over a sixteen weekperiod Positive and Negative Syndrome Scale(PANSS), Extrapyramidal Symptom(EPS), Nurses' Observation Scale for Inpatient Evaluation(NOSIE-30), Continuous Performance Test(CPT), Quality of Life(QOL), and haloperidol/reduced haloperidol blood levels were determined at the base line and after 2, 4, 6, 8, 12, 16 weeks to evaluate the dose reduction effects of high-dose antipsychotics. The results were as follows : 1) Dose-reduction is highly effective in reducing positive and negative symptoms, and general psychopathology. Effects were most prominent at 8, 12, 16 weeks. Among the dose reduction group, positive symptoms in positive symptom group and negative symptoms in negative symptom group were more reduced. 2 Extrapyramidal symptoms showed no significant difference between two groups. But the EPS was reduced time after time within two groups. 3) Hit rates of Continuous Performance Test, which indicate attentional capacity, increased significantly after dose reduction. 4) Haloperidol and reduced haloperidol blood levels decreased until the 4th week, after which they were constant. 5) Total scores of Nurses' Observation Scale for Inpatient Evaluation were unchanged between the two groups. But among the indices, social interest and personal neatness were improved in the dose-reduction group and retardation was aggrevated in the dose-maintaining group. 6) Total quality of life scores were unchanged between two groups. But in the dose maintaining group, satisfaction scores of attention, autonomy, and interpersonal relationship decreased progressively. These findings suggest that the dose reduction of antipsychotics for chronic schizophrenics on programs of high-dose antipsychotics were effective. Dose reduction should therefore be implemanted to spread the rehabilitation and improve quality of life for chronic schizophrenics.

• 방사선산업학회지
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• 제10권4호
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• pp.219-225
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• 2016

The apron is one of the essential protectors to reduce the exposure dose of radiological technologists. This study is to provide a guideline for purchasing the aprons with excellent performance and to help reducing the exposure dose by measuring the shielding ration and uniformity of aprons according to lead equivalent and form types. The shielding ratio of aprons were measured by using radiation generator and dosimeter. Exposure conditions were 81 kVp, 25 mAs, source to image receptor distance (SID) 100 cm and field of view (FOV) $17^{{\prime}{\prime}}{\times}17^{{\prime}{\prime}}$. Exposure areas for front type and around type aprons were divided into 9 areas and for 2 pieces type aprons were divided into 3 areas of top and 4 areas of skirt. The uniformity of aprons were measured by using fluoroscopy and Image J. The 4 regions of interest (ROI) were set into acquired images and measured uniformity by measuring the standard deviation of pixel intensity in ROIs. In continuous shielding ration measurement of aprons according to exposure area, there was not statistical significance (P>0.05). In ANOVA test of aprons, there was statistical significance (P<0.01). In the results of sheilding ratio, although the aprons had equal lead equivalent, there were difference in shielding ratio from 83.59% to 98.15%. In the results of uniformity, the front type aprons with equal lead equivalent indicated the similar uniformity. However, the around type and 2 pieces type apron with equal lead equivalent indicated the different uniformity each other, from 1.8 to 22.2. If the performance evaluation in this study were conducted regularly before and after purchase the aprons, the exposure does to patients and radiological technologists could be reduced.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.150-153
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• 2002

High dose rate (HDR) brachytherapy in the treatment of cervix carcinoma has become popular, because it eliminated many of the problems with conventional brachytherapy. In order to improve clinical effectiveness with HDR brachytherapy, dose calculation algorithm, optimization procedures, and image registrations should be verified by comparing the dose distributions from a planning computer and those from a humanoid phantom irradiated. Therefore, the humanoid phantom should be designed such that the dose distributions could be quantitatively evaluated by utilizing the dosimeters with high spatial resolution. Therefore, the small size of thermoluminescent dosimeter (TLD) chips with the dimension of 1/8" and film dosimetry with spatial resolution of <1mm used to measure the radiation dosages in the phantom. The humanoid phantom called a pelvic phantom is made of water and tissue-equivalent acrylic plates. In order to firmly hold the HDR applicators in the water phantom, the applicators are inserted into the grooves of the applicator supporters. The dose distributions around the applicators, such as Point A and B, can be measured by placing a series of TLD chips (TLD-to- TLD distance: 5mm) in three TLD holders, and placing three verification films in orthogonal planes.

• Radiation Oncology Journal
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• 제7권1호
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• pp.101-112
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• 1989

The treatment planning and dosimetry of small fields for stereotactic radiosurgery with 10 MV x-ray isocentrically mounted linear accelerator is presented. Special consideration in this study was given to the variation of absorbed dose with field size, the central axis percent depth doses and the combined moving beam dose distribution. The collimator scatter correction factors of small fields $(1\times1\~3\times3cm^2)$ were measured with ion chamber at a target chamber distance of 300cm where the projected fields were larger than the polystyrene buildup caps and it was calibrated with the tissue equivalent solid state detectors of small size (TLD, PLD, ESR and semiconductors). The central axis percent depth doses for $1\timesl\;and\;3\times3cm^2$ fields could be derived with the same acuracy by interpolating between measured values for larger fields and calculated zero area data, and it was also calibrated with semiconductor detectors. The agreement between experimental and calculated data was found to be under $2\%$ within the fields. The three dimensional dose planning of stereotactic focusing irradiation on small size tumor regions was performed with dose planning computer system (Therac 2300) and was verified with film dosimetry. The more the number of strips and the wider the angle of arc rotation, the larger were the dose delivered on tumor and the less the dose to surrounding the normal tissues. The circular cone, we designed, improves the alignment, minimizes the penumbra of the beam and formats ball shape of treatment area without stellate patterns. These dosimetric techniques can provide adequate physics background for stereotactic radiosurgery with small radiation fields and 10MV x-ray beam.