• Title/Summary/Keyword: 선량체적 히스토그램

Search Result 41, Processing Time 0.028 seconds

Dosimetric Influence of Implanted Gold Markers in Proton Therapy for Prostate Cancer (전립선암에 대한 양성자치료에서 금마커에 의한 방사선 선량분포의 영향)

  • Kwak, Jung-Won;Shin, Jung-Wook;Kim, Jin-Sung;Park, Sung-Yong;Shin, Dong-Ho;Yoon, Myong-Geun;Park, So-Ah;Kim, Dong-Wook;Lim, Young-Gyeung;Lee, Se-Byeong
    • Progress in Medical Physics
    • /
    • v.21 no.3
    • /
    • pp.291-297
    • /
    • 2010
  • This study examined the dosimetric influence of implanted gold markers in proton therapy and the effects of their positions in the spread-out Bragg peak (SOBP) proton beam. The implanted cylindrical gold markers were 3 mm long and 1.2 mm in diameter. The dosimetric influence of the gold markers was determined with markers at various locations in a proton-beam field. Spatial dose distributions were measured using a three-dimensional moving water phantom and a stereotactic diode detector with an effective diameter of 0.5 mm. Also, a film dosimetry was performed using Gafchromic External Beam Treatment (EBT) film. The GEANT4 simulation toolkit was used for Monte-Carlo simulations to confirm the measurements and to construct the dose-volume histogram with implanting markers. Motion data were obtained from the portal images of 10 patients to investigate the effect of organ motions on the dosimetric influence of markers in the presence of a rectal balloon. The underdosed volume due to a single gold marker, in which the dose was less than 95% of a prescribed amount, was 0.15 cc. The underdosed volume due to the presence of a gold marker is much smaller than the target volume. However, the underdosed volume is inside the gross tumor volume and is not smeared out due to translational prostate motions. The positions of gold markers and the conditions of the proton-beam field give different impacts on the dose distribution of a target with implanted gold markers, and should be considered in all clinical proton-based therapies.

Clinical Application Analysis of 3D-CRT Methods Using Tomotherapy (토모테라피를 이용한 3차원 입체 조형 치료의 임상적 적용 분석)

  • Cho, Kang-Chul;Kim, Joo-Ho;Kim, Hun-Kyum;Ahn, Seung-Kwon;Lee, Sang-Kyoo;Yoon, Jong-Won;Cho, Jeong-Hee;Lee, Jong-Seok;Yoo, Beong-Gyu
    • Journal of radiological science and technology
    • /
    • v.36 no.4
    • /
    • pp.327-335
    • /
    • 2013
  • This study investigates the case of clinical application for TomoDirect 3D-CRT(TD-3D) and TomoHelical 3D-CRT(TH-3D) with evaluating dose distribution for clinical application in each case. Treatment plans were created for 8 patients who had 3 dimensional conformal radiation therapy using TD-3D and TH-3D mode. Each patients were treated for sarcoma, CSI(craniospinal irradiaion), breast, brain, pancreas, spine metastasis, SVC syndrome and esophagus. DVH(dose volume histogram) and isodose curve were used for comparison of each treatment modality. TD-3D shows better dose distribution over the irradiation field without junction effect because TD-3D was not influenced by target length for sarcoma and CSI case. In breast case, dosimetric results of CTV, the average value of D 99%, D 95% were $49.2{\pm}0.4$ Gy, $49.9{\pm}0.4$ Gy and V 105%, V 110% were 0%, respectively. TH-3D with the dosimetric block decreased dose of normal organ in brain, pancreas, spine metastasis case. SCV syndrome also effectively decreased dose of normal organ by using dose block to the critical organs(spinal cord <38 Gy). TH-3D combined with other treatment modalities was possible to boost irradiation and was total dose was reduced to spinal cord in esophagus case(spinal cord <45 Gy, lung V 20 <20%). 3D-CRT using Tomotherapy could overcomes some dosimetric limitations, when we faced Conventional Linac based CRT and shows clinically proper dose distribution. In conclusion, 3D-CRT using Tomotherapy will be one of the effective 3D-CRT techniques.

Evaluation of Tangential Fields Technique Using TOMO Direct Radiation Therapy after Breast Partial Mastectomy (유방 부분 절제술 후 방사선 치료 시 TOMO Direct를 이용한 접선 조사의 선량적 유용성에 관한 고찰)

  • Kim, Mi-Jung;Kim, Joo-Ho;Kim, Hun-Kyum;Cho, Kang-Chul;Chun, Byeong-Chul;Cho, Jeong-Hee
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.23 no.1
    • /
    • pp.59-66
    • /
    • 2011
  • Purpose: Investigation of the clinical use of tangential fields technique using TOMO direct in comparison to conventional LINAC based radiation therapy after breast partial mastectomy. Materials and Methods: Treatment plans were created for 3 left-sided breast cancer patients who had radiation therapy after breast partial mastectomy by using wedged tangential fields technique, field in field technique (FIF), TOMO Direct, TOMO Direct intensity modulated radiation therapy (IMRT) under the normalized prescription condition ($D_{90%}$: 50.4 Gy/28 fx within CTV). Dose volume histogram (DVH) and isodose curve were used to evaluate the dose to the clinical target volume (CTV), organ at risk (OAR). We compared and analyzed dosimetric parameters of CTV and OAR. Dosimetric parameters of CTV are $D_{99}$, $D_{95}$, Dose homogeneity index (DHI: $D_{10}/D_{90}$) and $V_{105}$, $V_{110}$. And dosimetric parameters of OAR are $V_{10}$, $V_{20}$, $V_{30}$, $V_{40}$ of the heart and $V_{10}$, $V_{20}$, $V_{30}$ of left lung. Results: Dosimetric results of CTV, the average value of $D_{99}$, $D_{95}$ were $47.7{\pm}1.1Gy$, $49.4{\pm}0.1Gy$ from wedged tangential fields technique (W) and FIF (F) were $47.1{\pm}0.6Gy$, $49.2{\pm}0.4Gy$. And it was $49.2{\pm}0.4$ vs. $48.6{\pm}0.8Gy$, $49.9{\pm}0.4$ vs. $49.5{\pm}0.3Gy$ Gy for the TOMO Direct (D) and TOMO Direct IMRT (I). The average value of dose homogeneity index was W: $1.1{\pm}0.02$, F: $1.07{\pm}0.02$, D: $1.03{\pm}0.001$, I: $1.05{\pm}0.02$. When we compared the average value of $V_{105}$, $V_{110}$ using each technique, it was the highest as $34.6{\pm}9.3%$, $7.5{\pm}7.9%$ for wedged tangential fields technique and the value dropped for FIF as $16.5{\pm}14.8%$, $2.1{\pm}3.5%$, TOMO direct IMRT as $7.5{\pm}8.3%$, $0.1{\pm}0.1%$ and the TOMO direct showed the lowest values for both as 0%. Dosimetric results of OAR was no significant difference among each technique. Conclusion: TOMO direct provides improved target dose homogeneity over wedged tangential field technique. It is no increase the amount of normal tissue volumes receiving low doses, as oppose to IMRT or Helical TOMO IMRT. Also, it simply performs treatment plan procedure than FIF. TOMO Direct is a clinical useful technique for breast cancer patients after partial mastectomy.

  • PDF

Comparison of Beam Transfer Methods between Tomo Therapy and Proton Therapy for Prostate Cancer Radiation Therapy (전립선암 방사선 치료 시 토모치료와 양성자치료 빔 전달방식 비교)

  • Park, Jung Min;Ko, Eun Seo;Lee, Jin Hee;Kim, Jin Won;Yang, Jin Ho;Kwon, Kyung Tae
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.31 no.2
    • /
    • pp.75-81
    • /
    • 2019
  • Purpose: Tomo therapy and Proton therapy treatment plans for the treatment of prostate cancer patients were established, and the characteristics of dose distribution according to beam delivery method using Tomo therapy IMRT method and Proton therapy PBS method to compare and analyze the treatment effect were sought. Materials and Methods: Tomo IMRT treatment plan and Proton PBS treatment plan were established using the Hi.art planning station 5.1.1.6 of Tomo therapy and Eclipse 13.7 of VARIAN for three prostate cancer patients who were treated with radiotherapy only for radical purposes without surgery. For the evaluation of two treatment plans, the average dose (Dmean) and maximum dose (Dmax) of PGTV were calculated from dose volume histogram (DVH) to confirm the coverage and calculate CI and HI. In OAR evaluation, the dose received from the rectal volume 25% and the dose received from the bladder were evaluated to compare the normal long-term protection effect. Results: The mean maximum doses of the three patients were 71.4Gy, 75.3Gy and the mean doses were 70.4Gy and 72.8Gy in the DVH of the Tomo IMRT and Proton PBS. The CI was 1.16 and 1.31, and the HI was 0.04 and 0.12 respectively, and the Tomo IMRT was superior to the Proton PBS in dose suitability. Conclusion: The mean dose of PGTV in prostate cancer patients was 3.4% higher in Proton PBS than in Tomo IMRT. This is because the Dose suitability of Tomo IMRT was better, but it is considered to be a small difference to be seen as a significant result. However, the results of the two methods were 51.2% in D 25% and 55.7% less in the average dose of bladder, which could reduce the side effects of patients in proton PBS.

A Comparison for Treatment Planning of Tomotherapy and Proton Therapy in Prostate Cancer (전립선암에 대한 토모치료와 양성자치료의 치료계획 비교)

  • Song, Gwan-Soo;Bae, Jong-Rim;Kim, Jeong-Koo
    • Journal of radiological science and technology
    • /
    • v.36 no.1
    • /
    • pp.31-38
    • /
    • 2013
  • The prostate cancer is the most common malignant tumor in males. Prostate cancer is the most common malignant tumor that occurs in the male in Korea in 2007 to an annual average of 5,292 cases and 3.3% of the total cancer incidence seventh occurred. Our study compared property for tomotherapy and proton therapy in radiotherapy of prostate cancer patients. We analyzed DVH(Dose Volume Histogram) and dose distribution for prostate, bladder and rectum for radiation treatment planning of prostate cancer with 11 patients in Ilsan K cancer hospital from June to November 2011. There was no differences between tomotherapy and proton therapy in the purpose of prostate cancer therapy for PTV. The adjacent organs of bladder and rectum of average dose-volume were 2port proton therapy that it was low dose treatment comparing with tomotherapy and 5port proton therapy. $H{\cdot}I$ of proton therapy was less than $H{\cdot}I$ of tomotherapy. Also, 5port was less than 2port in $H{\cdot}I$ of proton therapy. However, 2port proton therapy has more advantage over 5port proton therapy that the bladder and rectum of average dose-volume and control time of equipment in radiotherapy of prostate cancer.

Effects of Arc Number or Rotation Range upon Dose Distribution at RapidArc Planning for Liver Cancer (간암환자를 대상으로 한 래피드아크 치료계획에서 아크수 및 회전범위가 선량분포에 미치는 영향)

  • Park, Hae-Jin;Kim, Mi-Hwa;Chun, Mi-Son;Oh, Yeong-Teak;Suh, Tae-Suk
    • Progress in Medical Physics
    • /
    • v.21 no.2
    • /
    • pp.165-173
    • /
    • 2010
  • In this paper, we evaluated the performance of 3D CRT, IMRT and three kind of RA plannings to investigate the clinical effect of RA with liver cancer case. The patient undergoing liver cancer of small volume and somewhat constant motion were selected. We performed 3D CRT, IMRT and RA plannings such as 2RA, limited triple arcs (3RA) and 3MRA with Eclipse version 8.6.15. The same dose volume objectives were defined for only CTV, PTV and body except heart, liver and partial body in IMRT and RA plannings. The steepness of dose gradient around tumor was determined by the Normal Tissue Objective function with the same parameters in place of respective definitions of dose volume objectives for the normal organs. The approach between the defined dose constraints and the practical DVH of CTV, PTV and Body was the best in 3MRA and the worst in IMRT. The DVHs were almost the same among RAs. Plans were evaluated using Conformity Index (CI), Homogeneity Index (HI) and Quality of coverage (QoC) by RTOG after prescription with dose level surrounding 98% of PTV in the respective plans. As a result, 3MRA planning showed the better favorable indices than that of the others and achieved the lowest MUs. In this study, RA planning is a technique that is possible to obtain the faster and better dose distribution than 3D CRT or IMRT techniques. Our result suggest that 3MRA planning is able to reduce the MUs further, keeping a similar or better targer dose homogeneity, conformity and sparing normal tissue than 2RA or 3RA.

Packing effects on the intracavitary radiation Therapy 3-Dimension plan of the uterine cervix cancer (자궁경부암 강내조사 3차원 치료계획 시 Packing의 유용성 분석)

  • Si, Chang-Keun;Jo, Jung-Kun;Lee, Du-Hyun;Kim, Sun-Yeung;Kim, Tae-Yoon
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.17 no.1
    • /
    • pp.1-8
    • /
    • 2005
  • Purpose : An effect of a packing to uterine treatment of a cervical cancer using a dose-volume histogram for a point dose and a volume dose of the bladder and the rectum was analyzed by establishing a three-dimensional treatment plan using a CT image. Materials and methods : Reference points of the bladder and the rectum were marked, respectively at a treatment plan device (plato brachytherapy V14.2.4) by photographing CT(marconi, USA) when the packing was used and removed under the same condition and a treatment plan was performed to Apoint depending on ICRU38. However, in case of the rectum, a maximum point was looked up and compared with the above point because the point presented from the ICRU is not proper as a representative value of a rectum point dose. Further, the volume dose depending on volume of $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder was measured. The measured values were used to analyze the effect of the packing through a Wilcoxon Signed Rank Test (a SAS statistical analysis process program). Result : The reference points at the bladder and rectum doses when the packing was removed were $116.94\;35.42\%$ and $117.59\;21.08\%$, respectively. The points when the packing was used were $107.08\;38.12\%$ and $95.19\;21.32\%$, respectively. After the packing was used, the reference points at the bladder and the rectum were decreased by $9.86\%$ and $22.4\%$, respectively. When the packing was removed, the maximum points at the bladder and the rectum were $164.51\;50.89\%,\;128.81\;33.05\%$, respectively. When the packing was used, the maximum points at the bladder and the rectum were $142.31\;44.79,\;110.08\;37.03\%$, respectively. After the packing was used, the maximum points at the bladder and the rectum were decreased by $22.2\%$ and $18.73\%$, respectively. When the packing was removed, the bladder volume at $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder were $48.62{\pm}18.09\%,\;16.12{\pm}11.15\%,\;and\;7.51{\pm}6.63\%$, respectively and its rectum volume were $23.41{\pm}14.44\%,\;6.27{\pm}4.28\%,\;2.79{\pm}2.27\%$, respectively. When the packing was used, the bladder volume at $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder were $40.33{\pm}16.72,\;11.63{\pm}8.72,\;and\;4.87{\pm}4.75\%$, respectively and its rectum volume were $18.96{\pm}8.37\%,\;4.75{\pm}2.58\%,\;and\;1.58{\pm}1.06\%$, respectively. After the packing was used, the bladder volume at $50\%,\;80\%,\;and\;100\%$ point doses of the rectum and the bladder were decreased by $8.29\%,\;4.49\%,\;and\;2.64\%$, respectively and its bladder volume were decreased by $4.45\%,\;1.52\%,\;and\;1.21\%$, respectively. Conclusion : Values at Reference point doses of the bladder and the rectum recommended from the ICRU 38 were 0.0781 and 0.0781, respectively and values of their maximum point doses were 0.0156 and 0.0156, respectively, as a result of which an effect of the packing using at the uterine intracavitary treatment of an uterine cervical cancer through the three-dimensional treatment plan used CT were measured. That is, the values at reference point doses and the values at maximum point doses show similar difference. However, P value was 0.15 at over $50\%,\;80\%,\;and\;100\%$ volume doses and the value shows no similar difference. In other words, the effect of the packing looks like having a difference at the point dose, but actually shows no difference at the volume dose. The reason is that the volume of the bladder and the rectum are wide but the volume of the packing is only a portion. Therefore, the effect of decreasing the point dose was not great. Further, the farer the distance is, the more weak the intensity of radiation is because the intensity of radiation is proportional to inverse square of a distance. Therefore, the effort to minimize an obstacle of the bladder and the rectum by using the packing should be made.

  • PDF

Comparison of Dosimetric Parameters of Patient with Large and Pendulous Breast Receiving Breast Radiotherapy in the Prone versus Supine Position (유방 크기가 큰 유방암 환자의 방사선 치료 시 환자의 자세에 따른 선량 비교)

  • Moon, Sun Young;Yoon, Myonggeun;Chung, Weon Kuu;Chung, Mijoo;Shin, Dong Oh;Kim, Dong Wook
    • Progress in Medical Physics
    • /
    • v.26 no.4
    • /
    • pp.234-240
    • /
    • 2015
  • The purpose of this study is to analyze dosimetric parameters of patient with large and pendulous breast receiving breast radiotherapy in the prone versus supine position. The patient underwent computed tomography simulation in both prone and supine position. The homogeneity index (HI), conformity index (CI), coverage index (CVI) to the left breast as planning target volume (PTV) and the doses to the lung, heart, and right breast as organ at risk (OAR) were compared by using dose-volume histogram. The lifetime attributable risk (LAR) according to the prone and supine position was measured for the lung and right breast. The HI, CI of the PTV decreased 21.7%, 6.49%, respectively and the CVI increased 10.8% with the prone position. The mean and maximum dose to the left lung decreased 91.6%, 87.0%, respectively and the volume parameters also decreased over 99% with the prone position. The parameters to the right lung were same regardless of the position. The mean and maximum dose to the heart decreased 51.6%, 14.2% with the prone position. But the mean and maximum dose to the right breast increased unlike the other OARs. The LARs to the lung decreased 80.3% (left), 24.2% (right) but the LAR to the right breast doubled with the prone position. The prone position is a favorable alternative for irradiation of breast in patients with large and pendulous breasts.

Development of Independent Target Approximation by Auto-computation of 3-D Distribution Units for Stereotactic Radiosurgery (정위적 방사선 수술시 3차원적 공간상 단위분포들의 자동계산법에 의한 간접적 병소 근사화 방법의 개발)

  • Choi Kyoung Sik;Oh Seung Jong;Lee Jeong Woo;Kim Jeung Kee;Suh Tae Suk;Choe Bo Young;Kim Moon Chan;Chung Hyun-Tai
    • Progress in Medical Physics
    • /
    • v.16 no.1
    • /
    • pp.24-31
    • /
    • 2005
  • The stereotactic radiosurgery (SRS) describes a method of delivering a high dose of radiation to a small tar-get volume in the brain, generally in a single fraction, while the dose delivered to the surrounding normal tissue should be minimized. To perform automatic plan of the SRS, a new method of multi-isocenter/shot linear accelerator (linac) and gamma knife (GK) radiosurgery treatment plan was developed, based on a physical lattice structure in target. The optimal radiosurgical plan had been constructed by many beam parameters in a linear accelerator or gamma knife-based radiation therapy. In this work, an isocenter/shot was modeled as a sphere, which is equal to the circular collimator/helmet hole size because the dimension of the 50% isodose level in the dose profile is similar to its size. In a computer-aided system, it accomplished first an automatic arrangement of multi-isocenter/shot considering two parameters such as positions and collimator/helmet sizes for each isocenter/shot. Simultaneously, an irregularly shaped target was approximated by cubic structures through computation of voxel units. The treatment planning method by the technique was evaluated as a dose distribution by dose volume histograms, dose conformity, and dose homogeneity to targets. For irregularly shaped targets, the new method performed optimal multi-isocenter packing, and it only took a few seconds in a computer-aided system. The targets were included in a more than 50% isodose curve. The dose conformity was ordinarily acceptable levels and the dose homogeneity was always less than 2.0, satisfying for various targets referred to Radiation Therapy Oncology Group (RTOG) SRS criteria. In conclusion, this approach by physical lattice structure could be a useful radiosurgical plan without restrictions in the various tumor shapes and the different modality techniques such as linac and GK for SRS.

  • PDF

Comparison of Anisotropic Analytic Algorithm Plan and Acuros XB Plan for Lung Stereotactic Ablative Radiotherapy Using Flattening Filter-Free Beams (비편평화여과기 빔을 이용한 폐 정위절제방사선치료를 위한 AAA와 Acuros XB 계산 알고리즘의 치료계획 비교)

  • Chung, Jin-Beom;Eom, Keun-Yong;Kim, In-Ah;Kim, Jae-Sung;Lee, Jeong-Woo;Hong, Semie;Kim, Yon-Lae;Park, Byung-Moon;Kang, Sang-Won;Suh, Tae-Suk
    • Progress in Medical Physics
    • /
    • v.25 no.4
    • /
    • pp.210-217
    • /
    • 2014
  • This study investigated the dosimetric effects of different dose calculation algorithm for lung stereotactic ablative radiotherapy (SABR) using flattening filter-free (FFF) beams. A total of 10 patients with lung cancer who were treated with SABR were evaluated. All treatment plans were created using an Acuros XB (AXB) of an Eclipse treatment planning system. An additional plans for comparison of different alagorithm recalcuated with anisotropic analytic algorithm (AAA) algorithm. To address both algorithms, the cumulative dose-volume histogram (DVH) was analyzed for the planning target volume (PTV) and organs at risk (OARs). Technical parameters, such as the computation times and total monitor units (MUs), were also evaluated. A comparison analysis of DVHs from these plans revealed the PTV for AXB estimated a higher maximum dose (5.2%) and lower minimum dose (4.2%) than that of the AAA. The highest dose difference observed 7.06% for the PTV $V_{105%}$. The maximum dose to the lung was also slightly larger in the AXB plans. The percentate volumes of the ipsilateral lung ($V_5$, $V_{10}$, $V_{20}$) receiving 5, 10, and 20 Gy were also larger in AXB plans than for AAA plans. However, these parameters were comparable between both AAA and AXB plans for the contralateral lung. The differences of the maximum dose for the spinal cord and heart were also small. The computation time of AXB plans was 13.7% shorter than that of AAA plans. The average MUs were 3.47% larger for AXB plans than for AAA plans. The results of this study suggest that AXB algorithm can provide advantages such as accurate dose calculations and reduced computation time in lung SABR plan using FFF beams, especially for volumetric modulated arc therapy technique.