• Journal of radiological science and technology
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• v.34 no.1
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• pp.59-64
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• 2011

We investigated the radiation exposure caused by DIPS, which is used to identify accurate repositioning and tumor location in pediatric cancer patients proton therapy. To compare and analyze DIPS condition, 50 pediatric cancer patients who underwent proton therapy were selected in Ilsan K cancer-specialized hospital from March 2007 to October 2009. For DIP exposure, 0.09~1.57 mGy is measured in AP and lateral directions and 23.55 mGy is measured in CSI patients. In whole brain patient, the amount of a day DIP exposure dose was 1.13 mGy. During treatment period, who exposed the biggest DIP dose are whole brain patients, 632.71 mGy is exposed. It is 1.13% of prescribed dose, represented dose is adequate because it is not exceeded 2% of recommended dose. Even though the exposed dose is not exceeded more than 2% of prescribed in DIP exposure, we should recognize the radiation damage and genetic influences to pediatric cancer patients, who is much sensitive to radiation and has longer mean residual life time. Therefore, DIPS guideline for pediatric cancer patients should be indicated to minimize the radiation exposure.

• Progress in Medical Physics
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• v.24 no.4
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• pp.278-283
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• 2013

Breast cancer is the leading cause of cancer death in women worldwide and the number of women breast cancer patient was increased continuously. Most of breast cancer patient has suffered from unnecessary radiation exposure to heart, lung. Low radiation dose to the heart could lead to the worsening of preexisting cardiovascular lesions caused by radiation induced pneumonitis. Also, several statistical reports demonstrated that left-sided breast cancer patient showed higher mortality than right-sided breast cancer patient because of heart disease. In radiation therapy, Deep Inspiration Breath Hold (DIBH) technique which the patient takes a deep inspiration and holds during treatment and could move the heart away from the chest wall and lung, has showed to lead to reduction in cardiac volume and to minimize the unnecessary radiation exposure to heart during treatment. In this study, we investigated the displacement of heart using DIBH CT data compared to free-breathing (FB) CT data and radiation exposure to heart. Treatment planning was performed on the computed tomography (CT) datasets of 10 patients who had received lumpectomy treatments. Heart, lung and both breasts were outlined. The prescribed dose was 50 Gy divided into 28 fractions. The dose distributions in all the plans were required to fulfill the International Commission on Radiation Units and Measurement specifications that include 100% coverage of the CTV with ${\geq}95%$ of the prescribed dose and that the volume inside the CTV receiving >107% of the prescribed dose should be minimized. Scar boost irradiation was not performed in this study. Displacement of heart was measured by calculating the distance between center of heart and left breast. For the evaluation of radiation dose to heart, minimum, maximum and mean dose to heart were calculated. The present study demonstrates that cardiac dose during left-sided breast radiotherapy can be reduced by applying DIBH breathing control technique.

• The Journal of Internal Korean Medicine
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• v.32 no.3
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• pp.334-344
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• 2011

Objectives : Sipjeondaebo-tang is a medicine traditionally prescribed as a restorative. The aim of this study was to investigate the single oral dose toxicity and safety of extract of fermented Sipjeondaebo-tang in ICR mice. Methods : In single oral dose toxicity study, non-fermented or fermented Sipjeondaebo-tang were administered by oral gavage to ICR mice (5 males, 5 females) at single doses of varying concentrations: 1250, 2500 and 5000 mg/kg. Changes of body weight, general behavior, adverse effects and mortality were determined throughout the experimental period. Hematological parameters, organ weights and necropsy findings were evaluated at the end of the experiment. Results : There were no mortality or signs of toxicity in single oral dose toxicity studies. There were also no significant differences in body weight, organ weight, or hematological parameters between the treatment and control groups. Conclusions : Fermented Sipjeondaebo-tang did not cause remarkable adverse effects in ICR mice. The oral lethal dose of fermented Sipjeondaebo-tang is more than 5000 mg/kg and no-observed-adverse-effect level (NOAEL) of the extract for both male and female mice is 5000 mg/kg.

• Progress in Medical Physics
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• v.33 no.4
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• pp.158-163
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• 2022

Purpose: We subjected scanning electron microscopic (SEM) images of the active layer of EBT3 film to texture analysis to determine the dose-response curve. Methods: Uncoated Gafchromic EBT3 films were prepared for direct surface SEM scanning. Absorbed doses of 0-20 Gy were delivered to the film's surface using a 6 MV TrueBeam STx photon beam. The film's surface was scanned using a SEM under 100× and 3,000× magnification. Four textural features (Homogeneity, Correlation, Contrast, and Energy) were calculated based on the gray level co-occurrence matrix (GLCM) using the SEM images corresponding to each dose. We used R-square to evaluate the linear relationship between delivered doses and textural features of the film's surface. Results: Correlation resulted in higher linearity and dose-response curve sensitivity than Homogeneity, Contrast, or Energy. The R-square value was 0.964 for correlation using 3,000× magnified SEM images with 9-pixel offsets. Dose verification was used to determine the difference between the prescribed and measured doses for 0, 5, 10, 15, and 20 Gy as 0.09, 1.96, -2.29, 0.17, and 0.08 Gy, respectively. Conclusions: Texture analysis can be used to accurately convert microscopic structural changes to the EBT3 film's surface into absorbed doses. Our proposed method is feasible and may improve the accuracy of film dosimetry used to protect patients from excess radiation exposure.

• Radiation Oncology Journal
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• v.34 no.4
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• pp.313-321
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• 2016

Purpose: Total scalp irradiation (TSI) is a rare but challenging indication. We previously reported that non-coplanar intensity-modulated radiotherapy (IMRT) was superior to coplanar IMRT in organ-at-risk (OAR) protection and target dose distribution. This consecutive treatment planning study compared IMRT with volumetric-modulated arc therapy (VMAT). Materials and Methods: A retrospective treatment plan databank search was performed and 5 patient cases were randomly selected. Cranial imaging was restored from the initial planning computed tomography (CT) and target volumes and OAR were redelineated. For each patients, three treatment plans were calculated (coplanar/non-coplanar IMRT, VMAT; prescribed dose 50 Gy, single dose 2 Gy). Conformity, homogeneity and dose volume histograms were used for plan. Results: VMAT featured the lowest monitor units and the sharpest dose gradient (1.6 Gy/mm). Planning target volume (PTV) coverage and homogeneity was better in VMAT (coverage, 0.95; homogeneity index [HI], 0.118) compared to IMRT (coverage, 0.94; HI, 0.119) but coplanar IMRT produced the most conformal plans (conformity index [CI], 0.43). Minimum PTV dose range was 66.8%-88.4% in coplanar, 77.5%-88.2% in non-coplanar IMRT and 82.8%-90.3% in VMAT. Mean dose to the brain, brain stem, optic system (maximum dose) and lenses were 18.6, 13.2, 9.1, and 5.2 Gy for VMAT, 21.9, 13.4, 14.5, and 6.3 Gy for non-coplanar and 22.8, 16.5, 11.5, and 5.9 Gy for coplanar IMRT. Maximum optic chiasm dose was 7.7, 8.4, and 11.1 Gy (non-coplanar IMRT, VMAT, and coplanar IMRT). Conclusion: Target coverage, homogeneity and OAR protection, was slightly superior in VMAT plans which also produced the sharpest dose gradient towards healthy tissue.

• Progress in Medical Physics
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• v.11 no.1
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• pp.85-90
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• 2000

In radiation therapy, the effects of radiation are decided total dose, total treatment times and number of radiation dose fractions. We considered that total dose, total treatment times and number of radiation dose fractions in intensity modulation radiation therapy(IMRT) infuence tumor cell killing. The goal of three dimensional conformal radiation therapy(3DCRT) in radiation therapy is to conform the partial distribution of the prescribed radiation dose to the precise 3D configuration of the tumor, and at the same time, to minimize the dose to the surrounding normal tissues. To optimize treatment volume of tumor, treatment volume will be same tumor volume. All IMRT compare to conventional treatment plus boost IMRT when total dose irradiated 75 - 90 Gy. Because of biological effect, total dose are decreased 12.5 - l5Gy in all IMRT.

• YAKHAK HOEJI
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• v.53 no.2
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• pp.83-88
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• 2009

Warfarin is the most widely used oral anticoagulant in the world but maintenance of proper therapeutic range and prevention of adverse drug events always need to be careful. Especially, in Korea, warfarin dosing for patients with cerebral infarction is currently based on the nomogram which is done by foreign clinical trials not for the Korean. Therefore we evaluate warfarin dose of patients in the neurology and eventually get the base data of warfarin nomogram for Korean with stroke. We performed this study retrospectively on reviewing the medical charts to evaluate the prescribed loading dose (LD) and maintenance dose (MD) of warfarin and each responding International Normalized Ratio (INR) with any bleeding adverse drug reaction including of patient's characteristics for total 75 patients with stroke in the department of neurology of Kangnam ST. Mary's Hospital from January 2005 to June 2008. All evaluated patients should not be treated with warfarin in the past at all and should be initiated warfarin therapy first.ly at this time. All evaluated patients were divided as two classes by wafarin LD which is; 1) HDG - a high loading dosing group prescribed over 5mg, and 2) LDG - a low loading dosing group prescribed 5mg or below. As a result, average LD was $9.34{\pm}0.22$ mg (p=0.000) in HDG and $4.25{\pm}0.39$ mg (p=0.000) in LDG. Average baseline INR was $0.91{\pm}0.05$ (p=0.161) in HDG and $1.26{\pm}0.14$ (p=0.002) in LDG. On the first and second week, daily MD was $4.21{\pm}0.14$ mg (p=0.000) and $2.96{\pm}0.19$ mg (p=0.696) in HDG and also in LDG, $2.95{\pm}0.29$ mg (p=0.000) and $3.14{\pm}0.36$ mg (p=0.696). Also average reacting daily INR was respectively $2.53{\pm}0.12$ (p=0.141) and $2.51{\pm}0.16$ (p=0.678) in HDG, and in LDG, $2.11{\pm}0.17$ (p=0.141) and $2.42{\pm}0.14$ (p=0.678). After the second week, INR was not measured in regularly. Also most of underlying diseases were hypertension (n=38), diabetes mellitus (n=14), dyslipidemia (n=8) in order. Four ADRs with simple hemorrhage were occurred and those were due to drug interaction by comedication. In the conclusion, proper starting LD for Korean with stroke is 10 mg if baseline INR is around 1.0 or 5 mg if over 1.3. Proper MD need to be more evaluated in the future for setting up warfarin nomogram to make prospective study.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2573-2577
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• 2016

Objective: The aim of this study was to determine a method of dose prescription that minimizes normal tissue irradiation outside the planning target volume (PTV) during stereotactic body radiotherapy (SBRT) for patients with non-small cell lung cancer. Methods: Previous research and patients with typical T1 lung tumors with peripheral lesions in the lung were selected for analysis. A PTV and several organs at risk (OARs) were constructed for the dose calculated; six treatment plans employing intensity modulated radiotherapy (IMRT) were produced, in which the dose was prescribed to encompass the PTV, with the prescription isodose level (PIL) set at 50, 60, 70, 80, 90 or 95% of the isocenter dose. Additionally, four OARs around the PTV were constructed to evaluate the dose received in adjacent tissues. Results: The use of higher PILs for SBRT resulted in improved sparing of OARs, with the exception of the volume of lung treated with a lower dose. Conclusions: The use of lower PILs is likely to create significant inhomogeneity of the dose delivered to the target, which may be beneficial for the control of tumors with poor conformity indices.

• The Korea Journal of Herbology
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• v.28 no.1
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• pp.51-58
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• 2013

Objectives : As Daily Dose of Zizyphi Fructus was designated by the numbers in Treatise on Cold Damage Disease, estimation of Daily Dose was all different among researchers. The purpose of this study was to estimate exact Daily Dose of Zizyphi Fructus. Methods : We fixed the errors in various copy of Treatise on Cold Damage Disease and considered the meaning of the Bee Zizyphi Fructus(肥大棗) and general rules of Daily Dose in Treatise on Cold Damage Disease. So we reduced Daily Dose of Zizyphi Fructus, and compared this with the standard of Zizyphy Fructus in Pharmacopoeia of several Nation and Korean Forest Service. Results : Daily Dose of Zizyphi Fructus was generally 12 pieces; less was for prescriptions which scaled down the amount of ingredients prescribed in the originals; 15, 25, and 30 pieces were used when more was required. The medicinal part was the pulp of fructus, and the dosage of 12 pieces was respectively equivalent to 3 Ryang(兩), and 19.5 g. As defined in the Korean Pharmacopoeia Ninth Edition and standards of forest products by Korea Forest Service, Zizyphi Fructus was medium-sized, and weighs about 1.625 g if properly dehydrated. Conclusions : In short, the proper Daily Dose of Zizyphi Fructus in Treatise on Cold damage Disease was 12 pieces of Zizyphi Fructus and 19.5 g of its pulp, weighing three Ryang(兩). The pulp was estimated to be 1.625 g; it was medium-sized according to the present standard.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5259-5264
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• 2014

Background: CT based brachytherapy allows 3-dimensional (3D) assessment of organs at risk (OAR) doses with dose volume histograms (DVHs). The purpose of this study was to compare computed tomography (CT) based volumetric calculations and International Commission on Radiation Units and Measurements (ICRU) reference-point estimates of radiation doses to the bladder and rectum in patients with carcinoma of the cervix treated with high-dose-rate (HDR) intracavitary brachytherapy (ICBT). Materials and Methods: Between March 2011 and May 2012, 20 patients were treated with 55 fractions of brachytherapy using tandem and ovoids and underwent post-implant CT scans. The external beam radiotherapy (EBRT) dose was 48.6Gy in 27 fractions. HDR brachytherapy was delivered to a dose of 21 Gy in three fractions. The ICRU bladder and rectum point doses along with 4 additional rectal points were recorded. The maximum dose ($D_{Max}$) to rectum was the highest recorded dose at one of these five points. Using the HDRplus 2.6 brachyhtherapy treatment planning system, the bladder and rectum were retrospectively contoured on the 55 CT datasets. The DVHs for rectum and bladder were calculated and the minimum doses to the highest irradiated 2cc area of rectum and bladder were recorded ($D_{2cc}$) for all individual fractions. The mean $D_{2cc}$ of rectum was compared to the means of ICRU rectal point and rectal $D_{Max}$ using the Student's t-test. The mean $D_{2cc}$ of bladder was compared with the mean ICRU bladder point using the same statistical test. The total dose, combining EBRT and HDR brachytherapy, were biologically normalized to the conventional 2 Gy/fraction using the linear-quadratic model. (${\alpha}/{\beta}$ value of 10 Gy for target, 3 Gy for organs at risk). Results: The total prescribed dose was $77.5Gy{\alpha}/{\beta}10$. The mean dose to the rectum was $4.58{\pm}1.22Gy$ for $D_{2cc}$, $3.76{\pm}0.65Gy$ at $D_{ICRU}$ and $4.75{\pm}1.01Gy$ at $D_{Max}$. The mean rectal $D_{2cc}$ dose differed significantly from the mean dose calculated at the ICRU reference point (p<0.005); the mean difference was 0.82 Gy (0.48-1.19Gy). The mean EQD2 was $68.52{\pm}7.24Gy_{{\alpha}/{\beta}3}$ for $D_{2cc}$, $61.71{\pm}2.77Gy_{{\alpha}/{\beta}3}$ at $D_{ICRU}$ and $69.24{\pm}6.02Gy_{{\alpha}/{\beta}3}$ at $D_{Max}$. The mean ratio of $D_{2cc}$ rectum to $D_{ICRU}$ rectum was 1.25 and the mean ratio of $D_{2cc}$ rectum to $D_{Max}$ rectum was 0.98 for all individual fractions. The mean dose to the bladder was $6.00{\pm}1.90Gy$ for $D_{2cc}$ and $5.10{\pm}2.03Gy$ at $D_{ICRU}$. However, the mean $D_{2cc}$ dose did not differ significantly from the mean dose calculated at the ICRU reference point (p=0.307); the mean difference was 0.90 Gy (0.49-1.25Gy). The mean EQD2 was $81.85{\pm}13.03Gy_{{\alpha}/{\beta}3}$ for $D_{2cc}$ and $74.11{\pm}19.39Gy_{{\alpha}/{\beta}3}$ at $D_{ICRU}$. The mean ratio of $D_{2cc}$ bladder to $D_{ICRU}$ bladder was 1.24. In the majority of applications, the maximum dose point was not the ICRU point. On average, the rectum received 77% and bladder received 92% of the prescribed dose. Conclusions: OARs doses assessed by DVH criteria were higher than ICRU point doses. Our data suggest that the estimated dose to the ICRU bladder point may be a reasonable surrogate for the $D_{2cc}$ and rectal $D_{Max}$ for $D_{2cc}$. However, the dose to the ICRU rectal point does not appear to be a reasonable surrogate for the $D_{2cc}$.