• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.2051-2054
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• 2015

Background: Radiation therapy is a key part of the combined modality treatment for Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL), which can achieve locoregional control of disease. The 3D-conformal radiation oncology can be extended-field (EFRT), involved-field (IFRT) and involved node (INRT). New techniques have resulted in a smaller radiation field and lower dose for critical organs such as lung heart and breast. Materials and Methods: In our research, we made a virtual simulation for one patient who was treated in four different radiotherapeutic techniques: mantle field (MFRT), EFRT, IFRT and INRT. After delineatiion we compared dose-volume histograms for each technique. The fusion of CT for planning radiotherapy with the initial PET/CT was made using Softver Xio 4.6 in the Focal program. The dose for all four techniques was 36Gy. Results: Our results support the use of PET/CT in radiation therapy planning. With IFRT and INRT, the burden on the organs at risk is less than with MFRT and EFRT. On the other hand, the dose distribution in the target volume is much better with the latter. Conclusions: The aim of modern radiotherapy of HL and NHL is to reduce the intensity of treatment and therefore PET/CT should be used to reduce and not increase the amount of tissue receiving radiation.

• Progress in Medical Physics
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• v.15 no.3
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• pp.167-172
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• 2004

A Siemens HD-270 MLC$^{TM}$, a virtual-micro MLC, allows to the application of a smooth field edge method due to the finite leaf-width of MLC. This technique was implemented into a Pinnacle planning system in order to evaluate the dose distributions during the planning stage. The necessary dosimetric aspects, such as undulation and effective penumbra, were investigated with variations in the resolutions of a virtual-micro MLC and field edge angle. The positional accuracy of the couch movement was also assessed for clinical implementation. The overhead time for planning and treatment was confirmed as negligible.e.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.547-550
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• 2011

We measured that is Gantry, Collimator Star Shot, Light vs. Radiation, HDR QA with Medical LINAC Then, PACS was implemented on the digital images on the monitor that can be confirmed through the QA. Also, for cooperation with OCS system that is using from present source and impose code that need in treatment in each treatment, did so that Order that connect to network, input to CR may appear, did so that can solve support data mistake of Pinacle and PACS that is Planning System and look at Planning premier in PACS.

• Progress in Medical Physics
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• v.35 no.1
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• pp.1-9
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• 2024

Margin inclusion or exclusion remains the most critical and controversial aspect of stereotactic radiosurgery (SRS) for metastatic brain tumors. This review aimed to examine the available literature on the impact of margins in SRS of brain metastasis and to assess the response of some medical physicists on the use of these margins. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses method was used to review articles published in PubMed, Embase, and Science Direct databases from January 2012 to December 2022 using the following keywords: planning target volume, brain metastasis, margin, and stereotactic radiosurgery. A simple survey consisting of five questions was completed by ten medical physicists with experience in SRS treatment planning. The results were analyzed using IBM SPSS Statistics version 26.0. Of the 1,445 articles identified, only 38 articles were chosen. Of these, eight papers were deemed relevant to the focus of this review. These papers showed an increase in the risk of radionecrosis, whereas differences in local control were variable as the margin increased. In the survey, the response rate to whether or not to use margins in SRS, a critical question, was 50%. Margin addition increases the risk of radio necrosis. The local control rate varies among treatment modalities and cannot be generalized. From the survey, no consensus was reached regarding the use of these margins. This calls for further deliberations among professionals directly involved in SRS.

• The Journal of Korean Society for Radiation Therapy
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• v.33
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• pp.145-153
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• 2021

Purpose: The purpose of this study is to evaluate the ovarian dose during radiation therapy for breast cancer in women of childbearing age through an experiment. The ovarian dose is evaluated by comparing and analyzing between the calculated dose in the treatment planning system according to the treatment technique and the measured dose using a thermoluminescence dosimeter (TLD). The clinical usefulness of lead (Pb) apron is investigated through dose analysis according to whether or not it is used. Materials and Methods: Rando humanoid phantom was used for measurement, and wedge filter radiation therapy, 3D conformal radiation therapy, and intensity modulated radiation therapy were used as treatment techniques. A treatment plan was established so that 95% of the prescribed dose could be delivered to the right breast of the Rando humanoid phantom 3D image obtained using the CT simulator. TLD was inserted into the surface and depth of the virtual ovary of the Rando hunmanoid phantom and irradiated with radiation. The measurement location was the center of treatment and the point moved 2 cm to the opposite breast from the center of the Rando hunmanoid phantom, 5cm, 10cm, 12.5cm, 15cm, 17.5cm, 20cm from the boundary of the right breast to the center of treatment and downward, and the surface and depth of the right ovary. Measurements were made at a total of 9 central points. In the dose comparison of treatment planning systems, two wedge filter treatment techniques, three-dimensional conformal radiotherapy, and intensity-modulated radiation therapy were established and compared. Treatments were compared, and dose measurements according to the use of lead apron were compared and analyzed in intensity-modulated radiation therapy. The measured value was calculated by averaging three TLD values for each point and converting using the TLD calibration value, which was calculated as the point dose mean value. In order to compare the treatment plan value with the actual measured value, the absolute dose value was measured and compared at each point (%Diff). Results: At Point A, the center of treatment, a maximum of 201.7cGy was obtained in the treatment planning system, and a maximum of 200.6cGy was obtained in the TLD. In all treatment planning systems, 0cGy was calculated from Point G, which is a point 17.5cm downward from the breast interface. As a result of TLD, a maximum of 2.6cGy was obtained at Point G, and a maximum of 0.9cGy was obtained at Point J, which is the ovarian dose, and the absolute dose was 0.3%~1.3%. The difference in dose according to the use of lead aprons was from a maximum of 2.1cGy to a minimum of 0.1cGy, and the %Diff value was 0.1%~1.1%. Conclusion: In the treatment planning system, the difference in dose according to the three treatment plans did not show a significant difference from 0.85% to 2.45%. In the ovary, the difference between the Rando humanoid phantom's treatment planning system and the actual measured dose was within 0.9%, and the actual measured dose was slightly higher. This did not accurately reflect the effect of scattered radiation in the treatment planning system, and it is thought that the dose of scattered radiation and the dose taken by CBCT with TLD inserted were reflected in the actual measurement. In dosimetry according to the with or without a lead apron, when a lead apron was used, the closer the distance from the treatment range, the more effective the shielding was. Although it is not clinically appropriate for pregnancy or artificial insemination during radiotherapy, the dose irradiated to the ovaries during treatment is not expected to significantly affect the reproductive function of women of childbearing age after radiotherapy. However, since women of childbearing age have constant anxiety, it is thought that psychological stability can be promoted by presenting the data from this study.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.131-134
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• 2005

This paper presents a computer-aided simulation and robotic-assisted execution technology of external fixation method to achieve fracture reduction and deformity correction in long bones. Combining the kinematic analysis with a graphic model of the tibia and the fixator allowed 3D simulation and visualization of the adjustments required to reduce fracture or correct bone deformity as a pre-operative planning tool. The developed robot model provided accurate deformity correction with small residual deformity based on the results of the planning. By incorporating the robot model with image-guided system and computer-aided planning, the integrated system could be useful for computer-aided pre-operative planning and robotic-assisted execution in fracture treatment and bone deformity surgery.

• Progress in Medical Physics
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• v.9 no.3
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• pp.175-184
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• 1998

The dose distribution evaluation program for the stereotactic radiosurgery treatment planning system using a gamma knife has been built in order to work on PC. And this custom-made dose distribution is compared with that of commercial treatment planning program. 201 source position of a radiation unit were determined manually using a gamma knife collimator draft and geometrical coordinates. Dose evaluation algorithm was modified for our purpose from the original KULA, a commercial treatment planning program. With the composed program, dose distribution at the center of a spherical phantom, 80 mm in diameter, was evaluated into axial, coronal and sagittal image per each collimator. Along with this evaluated data, the dose distribution at a arbitrary point of inside the phantom was compared with those from KULA. Radiochromic film was set up at the center of the phantom and was irradiated by gamma knife, for the verification of dose distribution. In result, the deviation of the dose distribution from that of KULA is less than ${\pm}$3%, which is equivalent to ${\pm}$0.3 mm in 50% isodose distribution for all examined coordinates and film verification. The custom-made program, GPl is proven to be a good tool for the stereotactic radiosurgery treatment planning program.

• Journal of Korean Society of Rural Planning
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• v.5 no.2 s.10
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• pp.24-29
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• 1999

The soil from constructed wetland system for sewage treatment was analyzed to examine physical and chemical characteristics. Clogging and lowered permeability were the physical matters of concern, and nutrient and salt accumulation were the chemical matters of concern. However, the soil properties of the constructed wetland system after 3 year operation demonstrated no degradation and still the soil works almost same as the initial stage. Encouragingly, no sludge accumulation was observed inside the system. Therefore, it implies that the wetland sewage treatment system can work continuously as long as it is operated and managed properly not to cause excessive pollutant loading.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.61-64
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• 2002

As intensity modulated radiation therapy compared with conventional radiation therapy, tumor target dose increased and normal tissues and critical organs dose reduced. In brain tumor, treatment planning of intensity modulated radiation therapy was practiced in 4MV, 6MV, 15MV X-ray energy. In these X-ray energy, was considered the dose distribution and dose volume histogram. As 4MV X-ray compared with 6MV and 15MV, maximum dose of right optic-nerve increased 10.1 %, 8.4%. Right eye increased 5.2%, 2.7%. And left optic-nerve, left eye, optic chiasm and brainstem incrased 1.7% - 5.2%. Even though maximum dose of PTV and these critical organs show different from 1.7% - 10.1% according to X-ray energies, these are a piont dose. Therefore in brain tumor, treatment planning of intensity modulated radiation therapy in 9 treatment field showed no relation with energy dependency.

• Radiation Oncology Journal
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• v.1 no.1
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• pp.47-53
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• 1983

CT scans obtained on 15 patients of head and neck malignant tumors were evaluated for their utility in ratiotherapy treatment planning. To evaluate the advantage of incorporating CT scans in radiotherapy treatment planning of head and neck malignant tumors, the dose distributions of treatment plan with and without CT scan were compared in 15 patients. And then the dose distributions of the first and second treatment plan were compared. 1. Tumor extend and localization were clearly delineated on CT scan in 12 of 15 cases (80%), suggestive in 2 (13.3%), and not seen in only one (6.7%) which had been in the postoperative state. 2. Tumor coverage after CT scan was adequate in 14 of 15 cases (93.3%) and not in only one. In one case of inadequate tumor coverage the target volume lay inside the field but reached within 0.5cm of the field margin (marginal miss). 3. The volume of normal tissue irradiated was reduced after CT scan in 12 of 15 cases (80%), increased in 1 (6.7%) and not changed in 2 (13.3%). 4. We could maximize the local control of disease and minimize unnecessary morbidity by delineating the location and extent of tumor and normal tissue with CT for treatment plannings.