• Title/Summary/Keyword: low doses

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Studies on the Simplified Hemagglutination Reaction to Pasteurella multocida and the Stabilization of Erythrocytes (Pasteurella multocida에 대(對)한 간이적혈구(簡易赤血球) 응집반응(凝集反應)과 적혈구(赤血球)의 안정화(安定化)에 관(關)한 연구(硏究))

  • Lee, Hak Cheul;Chung, Yung Gun;Kim, Kyo-Joon
    • Korean Journal of Veterinary Research
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    • v.10 no.1
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    • pp.11-23
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    • 1970
  • Recently Carter(1952) reported the capsule antigens of Pasteurella multocida could be divided into four serological types A,B,C and D by means of precipitation tests. Subsequently he showed that the most sensitive for identification of these types involved the use of capsule substance adsorbed by erythrocytes in hemagglutination test. It may be somewhat difficult to conduct the hemagglutination test in small laboratory, because relatively large amounts of antisera and erythrocytes of the human O type are required for the test. A simple method for serological typing of P. multocida was the slide agglutination test employed by Little et al. (1943) and Namioka et al. (1962), but this method is still in controversy. The author tried adapting Carter's hemagglutination method to the slide method so called "micromethod technique", and studied on the stabilization of erythrocytes for use of slide hemagglutination to P. multocida although many invesigators reported the stabilization of erythrocytes. The results obtained are summarized as follows: 1. A simplified method (slide method) for capsule typing of the organism was developed by adapting Carter's hemagglutination reaction(tube method). Antibody-containing serum can be diluted serially on Boerner's microtest slide with capillary or serological pipetts with a considerable accuracy. The slide reaction can be carried out with case on the slide by adding $0.05m{\ell}$ of antigen-sensitized erythrocytes suspension diluted to one percent on $0.05m{\ell}$ of serially diluted antibody-containing sera, and the final result can be read after 60 minutes at the room temperature ($15^{\circ}C$). 2. It is difficult to determine superiority of inferiority between the slide method and the tube method on the pattern of the reaction of hemagglutination. 3. The pH range of 6.6 to 8.3 is optimal for the slide hemagglutination reaction. 4. The antigen-sensitization against erythrocytes at $37^{\circ}C$ is optimal for the slide hemagglutination. 5. Both the doses and concentration of antigen do not influence the antigen-adsorbing capacity of erythrocytes. 6. The reduction of antigen-sensitizing hours does not influence the antigen-adsorbing capacity of erythrocytes even 30 minutes. 7. The tannic acid treatment against formalinized and non-formalinized erythrocytes showed no effect on the reaction of hemagglutination. 8. The erythrocytes preserved at $4^{\circ}C$ in the ACD solution do not decrease the reactivity on the reaction of hemagglutination for 60 days, while they begin slight hemolysis 30 days after preserving. 9. The stable preparation of erythrocytes can be obtained by treating the cells at $37^{\circ}C$ for 20 hours with from 4 to 8 percent of formalin in saline or buffer. These cells can be preserved at $4^{\circ}C$ for more than 8 months experimented without hemolysis. With low concentration of formalin, the cells were not sufficiently stabilized resulting in the hemolysis after short period of preservation at $4^{\circ}C$. 10. The erythrocytes treated with 16 percent of formalin remain constantly or increase the reactivity for the reaction of hemagglutination. On the contrary, the cells treated with I to 8 percent of formalin decrease the reactivity. 11. There is no difference between nontreated fresh erythrocytes and the erythrocytes preserved in the ACD solution on the reactivity against the hemagglutination, and the erythrocytes treated with 16 percent of formalin showed the reactivity of higher level than that of the above two kinds of erythrocytes. 12. There is no difference between the saline and the isotonic buffer solution on the reaction of hemagglutination.

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CYP450 1A1 and p53 expression and DNA adduct formation in the liver of rats treated with a single dose of aflatoxins (아플라톡신을 간회 투여한 랫드의 간에서 CYP450 1A1, p53의 발현과 DNA adduct의 형성)

  • Lee, Beom Jun;Lee, Sook Jin;Kim, Tae Myoung;Kim, Dae Joong;Nam, Sang Yoon;Hyun, Sang Hwan;Kang, Jong Koo;Hong, Jin Tae;Kim, Cheul Kyu;Yun, Young Won
    • Korean Journal of Veterinary Research
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    • v.44 no.4
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    • pp.507-513
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    • 2004
  • Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus that grow in improperly stored cereals. Aflatoxin B1 ($AFB_1$) is a potent hepatocarcinogen in a variety of experimental animals including human beings. In spite of a high attention to the hepatocarcinogenecity of $AFB_1$, the relative toxicity of aflatoxins ($AFB_2$ and $AFG_1$) is not fully clarified. Sprague-Dawley male rats were orally administered with $AFB_1$, $AFB_2$, and $AFG_1$ at the dose of 250 ${\mu}g/kg$ (additionally including a dose of $1250{\mu}g/kg $ for $AFB_1$) body weight. Animals were then killed at 12, 24 or 48 hrs following aflatoxin exposure. Subsequently the immunohistochemical examination of p53, cytochrome p450 1A1 (CYP450 1A1), and glutathione-S-transferase placental form (GST-P) were performed. The level of the 8-OxodG in the liver was determined. Expressions of CYP450 1A1 and p53 were high in the liver of rats through 48 hrs after treatment of $AFB_1$ at the single dose of $250{\mu}g/kg $. This pattern was more clear as increasing doses. The treatment of $AFB_2$ and $AFG_1$ did not affect the expression of CYP450 1A1 but it caused weak expression of p53. The activity of GST were not found in the liver of rats treated with aflatoxins. The formation of 8-OxodG by $AFB_1$ increased in a dose-dependent manner up to 24 hrs after a single treatment of $AFB_1$ thereafter decreased to the level of control. The treatment of $AFB_2$ and $AFG_1$ did not affect the levels of 8-OxodG in the liver of rats with increasing time. These results in the present study indicate that $AFB_1$ among aflatoxins with low comparable levels is the most toxic as determined by early biomarkers such as CYP450 1A1, p53, GST-P, and 8-OxodG.

Post-Exposure Prophylaxis of Varicella in Family Contact by Oral Acyclovir (가족 내 수두 환자와 접촉 후 경구 Acyclovir의 예방효과)

  • Kim, Sang Hee;Kim, Jong Hyun;Oh, Jin Hee;Hur, Jae Kyun;Kang, Jin Han;Koh, Dae Kyun
    • Pediatric Infection and Vaccine
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    • v.9 no.1
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    • pp.61-66
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    • 2002
  • Purpose : To determine wether varicella can be prevented by administration of oral acyclovir(ACV) during the incubation period of the disease. Methods : Starting 9 days after exposure to the index case in their families, ACV(40 mg/kg/day in four divided doses) was given orally to 20 exposed children for 5 days. Their clinical features was compared with those of 20 control subjects. Antibody titers to VZV were measured in both group 1 week and 4 weeks after finishing the oral ACV administration. Results : The mean age of family members with varicella(51.4 months) were significantly high compared to that of ACV prophylaxis group(28.5 months) and control group(31 months) (P<0.05). Among the 12 children with ACV prophylaxis who completed follow up blood sampling, nine children were diagnosed as VZV infection on the serologic test(75%). Among them six children showed positive VZV IgM on the first blood sample and two children showed serocoversion to positive IgM on the second test after ACV prophylaxis. One child who was negative on both IgM and IgG, showed positive IgG on the second test. The incidence of fever and severity of skin rashes were significantly low in children received oral ACV than in the control group. No or reduced number of maculopapular eruption were observed in the oral ACV group compared to multiple vesicles of the control group. Conclusion : In the present study, we observed that oral ACV prophylaxis to the family contacts is effective in reducing severity of skin lesion. It is likely that oral ACV 9 days after contact prevents or reduces blood dissemination of VZV. Little is known about clinical effect and immunity to the virus in exposed children with no varicella symptom after treatment. We propose the checking up antibody to VZV some period after oral ACV, and considering vaccination to whom with no antibody. But further more studies are needed to practical application of oral ACV for the postexposure prophylaxis of varicella.

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Detection Characteristics of PSL and TL Methods in Spices Irradiated with Different Radiation Sources (조사선원에 따른 향신료의 PSL과 TL 검지 특성)

  • Kim, Kyu-Heon;Kwak, Ji-Young;Kim, Jung-Ki;Hwang, Cho-Rong;Lee, Jae-Hwang;Park, Yong-Chjun;Kim, Jae-I;Jo, Tae-Yong;Lee, Hwa-Jung;Lee, Sang-Jae;Han, Sang-Bae
    • Journal of Radiation Industry
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    • v.7 no.1
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    • pp.15-21
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    • 2013
  • The detection characteristics of irradiated spices were investigated depending on radiation sources and doses by photostimulated luminescence (PSL) and Thermoluminescence (TL). 6 kinds of spices (turmeric, onion powder, red pepper, basil, parsley, black pepper) were irradiated at 0 to 10 kGy under ambient conditions by both a $^{60}Co$ gamma irradiator and an electron beam (EB) accelerator, respectively. The PSL analysis showed negative results for non-irradiated spices, while irradiated spices gave intermediate and positive value, which presented the limited potential of PSL technique. In TL measurement, TL glow curves on non-irradiated samples appeared at about $300^{\circ}C$ with low intensity. All irradiated samples were easily distinguishable through radiation-specific strong TL glow curves with maximum peak in range of $150{\sim}200^{\circ}C$. TL ratio ($TL_1/TL_2$) obtained by a re-irradiation step could verify the detection result of $TL_1$ glow curves, showing ratios lower than 0.1 in the non-irradiated sample and higher than 0.1 in irradiated ones. Therefore, in PSL measurement, the identification of irradiated spices showed more clear results in electron beam irradiated samples. TL analysis showed obvious difference between non-irradiated and irradiated samples in gamma ray and electron beam irradiated samples.

Influence of lime and phosphorus application on nutrient uptake by corn in newly reclaimed acidic soils -I. With special reference to P sources and distribution of Zn among leaves (산성신개간토양(酸性新開墾土壤)에서 석회(石灰) 및 인산(燐酸)이 옥수수의 양분(養分) 흡수(吸收)에 미치는 영향(影響) -I. 인산비종(燐酸肥種)과 아연(亞鉛)의 흡수(吸收) 및 엽위별분포(葉位別分布))

  • Kim, Young Koo;Hong, Chong Woon;Oh, Yong Taeg
    • Korean Journal of Soil Science and Fertilizer
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    • v.8 no.4
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    • pp.189-194
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    • 1975
  • On a newly reclaimed acidic soil, investigation was made to find out the influence of lime and P application at a largeg uantity on the uptake of Zn by corn and its distribution among the leaves, under afactorial combination with two levels of Zn, lime, and P. The results are summarized as following. 1. The application of lime for neutralization of soil significantly reduced the uptake of Zn by corn. 2. Liberal doses of P (5% of P absorption coefficient of soil; 500ppm) applied before sowing did not influence the uptake of Zn. 3. The concentration of Zn in bottom leaves better reflected the Zn uptake status of corn than the upper leaves. The concentration of Zn in bottom leaves responded clearly to the treatments of lime and Zn, while those of upper leaves tended to be constant unresponding to application of lime and Zn. 4. On the present experimental condition, the yield of corn was increased with the increase of P application. But the concentration of P in plant tissue remained constant under different P levels. 5. Application of lime (calcium hydroxide) on low P plots, depressed the yield of corn significantly. It was speculated that the lime applied at large dose made the applied P less available to corn.

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A Study on the Fabrication and Comparison of the Phantom for CT Dose Measurements Using 3D Printer (3D프린터를 이용한 CT 선량측정 팬텀 제작 및 비교에 관한 연구)

  • Yoon, Myeong-Seong;Kang, Seong-Hyeon;Hong, Soon-Min;Lee, Youngjin;Han, Dong-Koon
    • Journal of the Korean Society of Radiology
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    • v.12 no.6
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    • pp.737-743
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    • 2018
  • Patient exposure dose exposure test, which is one of the items of accuracy control of Computed Tomography, conducts measurements every year based on the installation and operation of special medical equipment under Article 38 of the Medical Law, And keep records. The CT-Dose phantom used for dosimetry can accurately measure doses, but has the disadvantage of high price. Therefore, through this research, the existing CT - Dose phantom was similarly manufactured with a 3D printer and compared with the existing phantom to examine the usefulness. In order to produce the same phantom as the conventional CT-Dose phantom, a 3D printer of the FFF method is used by using a PLA filament, and in order to calculate the CTDIw value, Ion chambers were inserted into the central part and the central part, and measurements were made ten times each. Measurement results The CT-Dose phantom was measured at $30.44{\pm}0.31mGy$ in the periphery, $29.55{\pm}0.34mGy$ CTDIw value was measured at $30.14{\pm}0.30mGy$ in the center, and the phantom fabricated using the 3D printer was measured at the periphery $30.59{\pm}0.18mGy$, the central part was $29.01{\pm}0.04mGy$, and the CTDIw value was measured at $30.06{\pm}0.13mGy$. Analysis using the Mann - Whiteney U-test of the SPSS statistical program showed that there was a statistically significant difference in the result values in the central part, but statistically significant differences were observed between the peripheral part and CTDIw results I did not show. In conclusion, even in the CT-Dose phantom made with a 3D printer, we showed dose measurement performance like existing CT-Dose phantom and confirmed the possibility of low-cost phantom production using 3D printer through this research did it.

Comparison of Doses of Single Scan PBS and Layered Rescanning PBS Using Moving Phantom in Proton Therapy (양성자 치료에서 Moving Phantom을 이용한 Single Scan PBS와 Layered Rescanning PBS의 선량비교)

  • Kim, Kyeong Tae;Kim, Seon Yeong;Kim, Dae Woong;Kim, Jae Won;Park, Ji Yeon;Jeon, Sang Min
    • The Journal of Korean Society for Radiation Therapy
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    • v.31 no.1
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    • pp.43-49
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    • 2019
  • Purpose : We apply the Layered Rescanning PBS designed to complement the Pencil Beam Scanning(PBS), which is vulnerable to moving organs with the Moving Phantom, and compare the homogeneity with the single scan PBS. Methods and materials: Matrix X (IBA, Belgium) and Moving Phantom (standard imaging, USA) were used. A dose of 200 cGy was measured in the AP direction on a hypothetical tumor $10{\times}10{\times}5cm$. The plan type was planned as 4 kinds of sinlge scan PBS, rescan number 4, 8, 12 times. Were measured three times for each types. During the measurement, the respiratory cycle of the Moving Phantom was generally set to 4 seconds per cycle, and the movement radius in the S-I direction was set to 2 cm. In addition, beam on time was measured. Results : The mean values of $D_{max}$ in the PTV were $246.47{\pm}18.8cGy$, $223.43{\pm}8.92cGy$, and $222.47{\pm}7.7cGy$, $213.9{\pm}6.11cGy$ and the mean values of $D_{min}$ were $165.53{\pm}4.32cGy$, $173.13{\pm}11.94cGy$, $184.13{\pm}8.04cGy$, $182.67{\pm}4.38cGy$ and the mean values of $D_{mean}$ $192.77{\pm}6.98cGy$, $196.7{\pm}4.01cGy$, $198.17{\pm}4.96cGy$, $195.77{\pm}3.15cGy$ respectively. As the number of rescanning increased, the Homogeneity Index converged to 1. The beam on time was measured as 2:15, 3:15, 4:30, 5:37 on average. In the measurement process, in the low dose layer of the MU, the problem was found that it was not rescanned as many times as the set number of rescan. Conclusions : In the treatment of tumors with long-term movements, the application of layered rescanning PBS showed a more uniform dose distribution than single scan PBS. And as the number of rescan increase, the distribution of homogeneity is uniform. Compared with single scan plan and 12 rescan plan, HI value was improved by 0.32. Further studies are expected to be applicable to patients who can not be treated with respiratory synchronous radiation therapy.

Generative Adversarial Network-Based Image Conversion Among Different Computed Tomography Protocols and Vendors: Effects on Accuracy and Variability in Quantifying Regional Disease Patterns of Interstitial Lung Disease

  • Hye Jeon Hwang;Hyunjong Kim;Joon Beom Seo;Jong Chul Ye;Gyutaek Oh;Sang Min Lee;Ryoungwoo Jang;Jihye Yun;Namkug Kim;Hee Jun Park;Ho Yun Lee;Soon Ho Yoon;Kyung Eun Shin;Jae Wook Lee;Woocheol Kwon;Joo Sung Sun;Seulgi You;Myung Hee Chung;Bo Mi Gil;Jae-Kwang Lim;Youkyung Lee;Su Jin Hong;Yo Won Choi
    • Korean Journal of Radiology
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    • v.24 no.8
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    • pp.807-820
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    • 2023
  • Objective: To assess whether computed tomography (CT) conversion across different scan parameters and manufacturers using a routable generative adversarial network (RouteGAN) can improve the accuracy and variability in quantifying interstitial lung disease (ILD) using a deep learning-based automated software. Materials and Methods: This study included patients with ILD who underwent thin-section CT. Unmatched CT images obtained using scanners from four manufacturers (vendors A-D), standard- or low-radiation doses, and sharp or medium kernels were classified into groups 1-7 according to acquisition conditions. CT images in groups 2-7 were converted into the target CT style (Group 1: vendor A, standard dose, and sharp kernel) using a RouteGAN. ILD was quantified on original and converted CT images using a deep learning-based software (Aview, Coreline Soft). The accuracy of quantification was analyzed using the dice similarity coefficient (DSC) and pixel-wise overlap accuracy metrics against manual quantification by a radiologist. Five radiologists evaluated quantification accuracy using a 10-point visual scoring system. Results: Three hundred and fifty CT slices from 150 patients (mean age: 67.6 ± 10.7 years; 56 females) were included. The overlap accuracies for quantifying total abnormalities in groups 2-7 improved after CT conversion (original vs. converted: 0.63 vs. 0.68 for DSC, 0.66 vs. 0.70 for pixel-wise recall, and 0.68 vs. 0.73 for pixel-wise precision; P < 0.002 for all). The DSCs of fibrosis score, honeycombing, and reticulation significantly increased after CT conversion (0.32 vs. 0.64, 0.19 vs. 0.47, and 0.23 vs. 0.54, P < 0.002 for all), whereas those of ground-glass opacity, consolidation, and emphysema did not change significantly or decreased slightly. The radiologists' scores were significantly higher (P < 0.001) and less variable on converted CT. Conclusion: CT conversion using a RouteGAN can improve the accuracy and variability of CT images obtained using different scan parameters and manufacturers in deep learning-based quantification of ILD.

The Study of Dose Change by Field Effect on Atomic Number of Shielding Materals in 6 MeV Electron Beam (6 MeV 전자선의 차폐물질 원자번호와 조사야 크기에 따른 선량변화 연구)

  • Lee, Seung Hoon;Kwak, Keun Tak;Park, Ju Kyeong;Gim, Yang Soo;Cha, Seok Yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.25 no.2
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    • pp.145-151
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    • 2013
  • Purpose: In this study, we analyzed how the dose change by field size effects on atomic number of shielding materials while using 6 MeV election beam. Materials and Methods: The parallel plate chamber is mounted in $25{\times}25cm^2$ the phantom such that the entrance window of the detector is flush with the phantom surface. phantom was covered laterally with aluminum, copper and lead which thickness have 5% of allowable transmission and then the doses were measured in field size $6{\times}6$, $10{\times}10$ and $20{\times}20cm^2$ respectively. 100 cGy was irradiated using 6 MeV electron beam and SSD (Source Surface Distance) was 100 cm with $10{\times}10cm^2$ field size. To calculate the photon flux, electron flux and Energy deposition produced after pass materals respectively, MCNPX code was used. Results: The results according to the various shielding materials which have 5% of allowable transmission are as in the following. Thickness change rate with field size of $6{\times}6cm^2$ and $20{\times}20cm^2$ that compared to the field size of $10{\times}10cm^2$ found to be +0.06% and -0.06% with aluminum, +0.13% and -0.1% with copper, -1.53% and +1.92% with lead respectively. Compare to the field size $10{\times}10cm^2$, energy deposition for $6{\times}6cm^2$ and $20{\times}20cm^2$ had -4.3% and +4.85% respectively without shielding material. With aluminum it had -0.87% and +6.93% respectively and with lead it had -4.16% and +5.57% respectively. When it comes to photon flux with $6{\times}6cm^2$ and $20{\times}20cm^2$ of field sizes the chance -8.95% and +15.92% without shielding material respectively, with aluminum the number -15.56% and +16.06% respectively and with copper the chance -12.27% and +15.53% respectively, with lead the number +12.36% and -19.81% respectively. In case of electron flux in the same condition, the number -3.92% and +4.55% respectively without shielding material respectively, with aluminum the number +0.59% and +6.87% respectively, with copper the number -1.59% and +3.86% respectively, with lead the chance -5.15% and +4.00% respectively. Conclusion: In this study, we found that the required thickness of the shielding materials got thinner with low atomic number substance as the irradiation field is increasing. On the other hand, with high atomic number substance the required thickness had increased. In addition, bremsstrahlung radiation have an influence on low atomic number materials and high atomic number materials are effected by scattered electrons.

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Survival and Complication Rate of Radiation Therapy in Stage I and II Carcinoma of Uterine Cervix (병기 I, II 자궁 경부암에서 방사선치료 후 생존율 및 합병증 분석)

  • Ma, Sun-Young;Cho, Heung-Lea;Sohn, Seung-Chang
    • Radiation Oncology Journal
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    • v.13 no.4
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    • pp.349-357
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    • 1995
  • Purpose : To analyze survival rate and late rectal and bladder complication for patients with stage I and II carcinoma of uterine cervix treated by radiation alone or combined with chemotherapy Materials and Methods : Between November 1984 and December 1993, 127 patients with stage I and II carcinoma of uterine cervix treated by radiation alone or combined therapy of radiation and chemotherapy. Retrospective analysis for survival rate was carried out on eligible 107 patients and review for complication was possible in 91 patients. The median follow-up was 47 months (range 3-118) and the median age of patiens was 56 years (range 31-76). 26 patients were stage IB by FIGO classification, 40 were stage IIA and 41 were stage IIB. 86 cases were treated by radiation alone and 21 were treated by radiation and chemotherapy. 101 patients were treated with intracavitary radiation therapy (ICRT), of these, 80 were received low dose rate (LDR) ICRT and 21 were received high dose rate (HDR) ICRT. Of the patients who received LDR ICRT, 63 were treated by 1 intracavitary insertion and 17 were underwent 2 insertions And we evaluated the external radiation dose and midline shield. Results : Actuarial survival rate at 5 years was $92{\%}$ for stage IB, $75{\%}$ for stage IIA, $53{\%}$ for stage IIB and $69{\%}$ in all patients Grade 1 rectal complications were developed in 20 cases ($22{\%}$), grade 2 were in 22 cases ($24{\%}$). 22 cases ($24{\%}$) of grade 1 urinary complications and 17 cases ($19{\%}$) of grade 2 urinary complications were observed But no patient had severe complications that needed surgical management or admission care. Maximum bladder dose for the group of patients with urinary complications was higher than that for the patients without urinary complications (7608 cGy v 6960cGy. p<0.01) Maximum rectal dose for the group of patients with rectal complications was higher than that for the patients without rectal complications (7041cGy v 6269cGy, p<0.01). While there was no significant difference for survival rate or bladder complication incidence as a function of dose to whole pelvis, Grade 2 rectal complication incidence was significantly lower for the patients receiving less than 4500cGy ($6.3{\%}$ v $25.5{\%}$, p<0.05). There was no significant differance between HDR ICRT group and LDR ICRT group for survival rate according to stage, on the other hand complication incidence was higher in the HDR group than LDR group, This was maybe due to different prescription doses between HDR group and LDR group. Midline shield neither improved survival rate nor decreased complication rate. The number of insertion in LDR ICRT group did not affect on survival and compication rate. Conclusion : In stage I and II carcinoma of uterine cervix there was no significant differance for 5 year survival rate by radiation therapy technique. Rectal complication incidence was as a function of dose to whole pelvis and there were positive correlations of maximum dose of rectum and bladder and each complication incidence. So we recommand whole pelvis dose less than 4500cGy and maximum dose of rectum and bladder as low as possible.

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