• 제목/요약/키워드: Dose fractionations

검색결과 4건 처리시간 0.023초

자궁경부암의 고선량율 강내치료 선량계획 분석 (Analysis of High Dose Rate Intracavitary Radiotherapy(HDR-ICR) Treatment Planning for Uterine Cervical Cancer)

  • 채규영
    • Radiation Oncology Journal
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    • 제12권3호
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    • pp.387-392
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    • 1994
  • Purpose : This study was done to confirm the reference point variation according to variation in applicator configuration in each fractioation of HDR ICR. Materials and Methods : We analyzed the treatment planning of HDRICR for 33 uterine cervical cancer patients treated in department of therapeutic radiology from January 1992 to February 1992. Analysis was done with respect to three view points-Interfractionation A point variation, interfractionation bladder and rectum dose ratio variation, interfractionation treatment volume variation. Interfractionation A point variation was defined as difference between maximum and minimum distance from fixed rectal point to A point in each patient. Interfractionation bladder and rectum dose ratio variation was defined as difference between maximum and minimum dose ratio of bladder or rectum to A point dose in each patient, Interfractionation treatment volume variation was defined as difference between miximum and minimum treatment volume which absorbed over the described dose-that is, 350 cGy or 400 cGy-in each patient. Results The mean of distance from rectum to A point was 4.44cm, and the mean of interfractionation distance variation was 1.14 cm in right side,1.09 cm in left side. The mean of bladder and rectum dose ratio was $63.8\%$ and $63.1\%$ and the mean of interfractionation variation was $14.9\%$ and $15.8\%$ respectively. With fixed planning administration of same planning to all fractionations as in first fractionation planning-mean of bladder and rectum dose ratio was $64.9\%$ and $72.3\%$.and the mean of interfraction variation was $28.1\%$ and $48.1\%$ reapectively. The mean of treatment volume was $84.15cm^3$ and the interfractionation variation was $21.47cm^2$. Conclusion : From these data, it was confirmed that there should be adapted planning for every fractionation ,and that confirmation device installed in ICR room would reduce the interfractionation variation due to more stable applicator configuration.

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Is higher dose always the right answer in stereotactic body radiation therapy for small hepatocellular carcinoma?

  • Lee, Kyung Hwa;Yu, Jeong Il;Park, Hee Chul;Park, Su Yeon;Shin, Jung Suk;Shin, Eun Hyuk;Cho, Sungkoo;Jung, Sang Hoon;Han, Young Yih;Lim, Do Hoon
    • Radiation Oncology Journal
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    • 제36권2호
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    • pp.129-138
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    • 2018
  • Purpose: This study was conducted to compare clinical outcomes and treatment-related toxicities after stereotactic body radiation therapy (SBRT) with two different dose regimens for small hepatocellular carcinomas (HCC) ${\leq}3cm$ in size. Materials and Methods: We retrospectively reviewed 44 patients with liver-confined HCC treated between 2009 and 2014 with SBRT. Total doses of 45 Gy (n = 10) or 60 Gy (n = 34) in 3 fractions were prescribed to the 95% isodose line covering 95% of the planning target volume. Rates of local control (LC), intrahepatic failure-free survival (IHFFS), distant metastasis-free survival (DMFS), and overall survival (OS) were calculated using the Kaplan-Meier method. Results: Median follow-up was 29 months (range, 8 to 64 months). Rates at 1 and 3 years were 97.7% and 95.0% for LC, 97.7% and 80.7% for OS, 76% and 40.5% for IHFFS, and 87.3% and 79.5% for DMFS. Five patients (11.4%) experienced degradation of albumin-bilirubin grade, 2 (4.5%) degradation of Child-Pugh score, and 4 (9.1%) grade 3 or greater laboratory abnormalities within 3 months after SBRT. No significant difference was seen in any oncological outcomes or treatment-related toxicities between the two dose regimens. Conclusions: SBRT was highly effective for local control without severe toxicities in patients with HCC smaller than 3 cm. The regimen of a total dose of 45 Gy in 3 fractions was comparable to 60 Gy in efficacy and safety of SBRT for small HCC.

한국산 생약제들의 혈압강하작용에 대한 연구 II. 한국산 후박수피의 혈압강하 작용 (Pharmacological Action of Machilus Thunbergii Siebold Zuccarini)

  • 조병헌;김인호;이상복;조규철;이종화
    • 대한약리학회지
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    • 제15권1_2호
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    • pp.45-56
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    • 1979
  • With a view to searching after a new antihypertensive or hypotensive agents in the botanical crude plants, authors intended to reevaluate several natural products caltivated in Korea. This experiment was undertaken to compare pharmacogical actions of Machilus thunbergii Siebold et Zuccarini with those of Magnolia obovata Thunberg in anesthetized rats and in normal mice. Machilus thunbergii Sieb. et Zucc., a tree belonging to the Lauraceae family, is caltivated at Ull-ung Do, and their cortecies have been used as folk medicine mingled with those of Magnolia obovata Thunberg. These two cortecies have teen also applied in chinese medicine, it was advocated that these cortecies exerted good therapeutic effects on gastritis, convulsive abdominal pain, nausea, vomiting and urinary tract disorders. Therefore, we intended to determine the pharmacological action of two palnt of different family each other, especially their effects on blood pressure and heart rate, and also their mechanism of action were observed. We studied their action with extracts of hexane(MTHE), ether(MTEE), methanol(MTME) and water(MTWE) from Machilus thunhergii Sieb. et Zucc., and also fractionations of methanol(MOME), chloroform(MOCE) and water(MOWE) from Mapolia obovata Thunberg. The results of this experiment were as follows; 1) MTME, when intravenously administered to rats, elicited the significant hypotensive responses dependent on the administered dosage. 2) MOWE was also exhibited the hypotensive effect dependent on the treated dose. 3) Depressor effect of MTME was blocked by pretreatment with hexamethonium. 4) The hypotensive response of MOWE was blocked by pretreatment with hexamethonium or hrdralazine. 5) HTME and MOWE were also observed the anticonvulsive effect and sedative effect. These results suggested that MTME may induce the hypotensive response via central sympathetic effect, but the site of action in brain are not clarified, and the hypotensive effect of MOWE may be due to dual mechanism of central sympathetic action and direct vasodilation of blood vessel.

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전립선암의 소분할 방사선치료 시에 위치표지자 삽입의 유용성 (Clinical Usefulness of Implanted Fiducial Markers for Hypofractionated Radiotherapy of Prostate Cancer)

  • 최영민;안성환;이형식;허원주;윤진한;김태효;김수동;윤성국
    • Radiation Oncology Journal
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    • 제29권2호
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    • pp.91-98
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    • 2011
  • 목 적: 전립선암의 소분할 방사선치료에서 골반뼈를 기준으로 한 준비자세(setup)와 전립선에 삽입된 위치표지자(fiducial marker)를 이용한 준자세를 비교하였다. 대상 및 방법: 2009년 9월부터 2010년 8월까지 전립선암으로 근치적 소분할 방사선치료를 받은 4명의 환자를 대상으로 하였다. 방사선치료 1주일 전경에 경직장초음파 검사 하여 3개의 위치표지자를 직장을 통하여 전립선에 삽입하였다. 방사선치료계획용 컴퓨터단층촬영과 매 방사선치료 전에 직장 관장을 하였다. 소분할 방사선치료는 노발리스 장치를 이용하여, 매일 3.5 Gy씩 총 59.5 Gy를 계획하였다. 분할조사 전에 서로 수직인 두 방향의 kV X-선을 촬영하여 얻은 영상의 위치표지자와 방사선치료계획의 디지털재구성사진에서 관찰되는 위치표지자를 융합하여, 환자의 자세를 조정하고 준비자세를 하였다. 위치표지자 기준 준비자세에서 방사선치료계획의 디지털재구성사진과 kV X-선 영상의 골반뼈를 가상적으로 융합하여, 골반뼈 기준 준비자세를 구하였다. 결 과: 67회의 분할조사를 분석하였다. 위치표지자 기준 준비자세에서 방사선치료 중심점과의 3차원적 위치 차이의 평균은 $0.94{\pm}0.62$ mm (범위, 0.09~3.01 mm; 중앙값 0.81 mm)였고 좌우, 상하, 전후 방향으로 위치 차이의 평균은 각각 $0.39{\pm}0.34$ mm, $0.46{\pm}0.34$ mm, $0.57{\pm}0.59$ mm였다. 골반뼈 기준 준비자세에서 방사선치료 중심점과의 3차원적 위치 차이의 평균은 $3.15{\pm}2.03$ mm (범위, 0.25~8.23; 중앙값, 2.95 mm)였고, 상하 방향의 위치 차이(평균, $2.29{\pm}1.95$ mm)가 전후(평균, $1.73{\pm}1.31$ mm), 좌우(평균 $0.45{\pm}0.37$ mm) 방향보다 유의하게 컸다(p<0.05). 위치표지자 기준 준비자세와 골반뼈 기준 준비자세들에서 방사선치료 중심점과의 3차원적 위치 차이가 3 mm 이상이었던 경우는 전체 분할방사선조사 횟수의 1.5%와 49.3%였고, 5 mm 이상이었던 경우가 각각 0%, 17.9%였다. 결 론: 위치표지자를 이용하여 보다 정확하게 준비자세를 함으로써 계획용표적체적의 여유를 줄일 수 있고, 따라서 전립선 주변의 정상조직에 대한 방사선량을 감소시켜 보다 안전하게 소분할 방사선치료를 할 수 있을 것으로 예상된다.