Meditsinskaya Fizika最新文献

{"title":"Calibration of Thermoluminescent Dosimeters for Use in Photon Radiation Beams of Various Quality","authors":"I. D. Uhanov, I. Lebedenko","doi":"10.52775/1810-200x-2023-98-2-114-124","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-98-2-114-124","url":null,"abstract":"Purpose: To describe the technology of dosimetric preparation of the same batch of TLD based on LiF \u0000activated by magnesium Mg and titanium Ti (LiF:Mg-Ti) for three qualities of photon radiation beams \u0000with energies of 1.25 MeV, 2 MeV and 192Ir beam with energy of 0.38 MeV for measurements during radiotherapy. The TLD calibration technology for 192Ir should be developed from scratch. To compare the \u0000energy dependences of the sensitivity coefficients for different qualities of the beams. \u0000Material and methods: 175 dosimeters were irradiated in photon radiation beams with al energy of \u00002 MeV, 1.25 MeV and 0.38 MeV in a reproducible geometry several times determined by the same dose. \u0000Individual coefficients are obtained. A working batch of 12 TLD was selected with a production capacity \u0000of 2 %. Coefficients are estimated for the batch and graphs of the energy dependence of individual sensitivity coefficients are constructed. \u0000Results: The results obtained indicate the presence of an energy dependence of the individual sensitivity coefficients of TLD in the energy range from 0.38 to 1.0 MeV.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121705065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation Therapy of Patients with Regional Risk Group of Prostate Cancer","authors":"P. Bulychkin, S. Tkachev, M. Chernykh, V. Matveev, A. V. Khachaturyan, A. Klimov, A. A. Kufelkina","doi":"10.52775/1810-200x-2023-98-2-107-113","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-98-2-107-113","url":null,"abstract":"Relevance: Radiation therapy is one of the main local method of treatment for patients with prostate \u0000cancer and regional metastases of pelvic lymph nodes. However, unfortunately, some patients can be \u0000subject to development progression of disease as emergence regional lymph node’s metastasis of \u0000retroperitoneal space. \u0000Purpose: To develop a new more effective radical method of radiation therapy for patients with metastases in the regional lymph nodes. \u0000Material and methods: The radiotherapy department has developed a new method of radiation therapy \u0000for patients with prostate cancer and metastases in the regional lymph nodes, which includes prophylactic irradiation of retroperitoneal lymph nodes. \u0000Results: 20 patients with prostate cancer and metastases to the regional lymph nodes were treated \u0000from June 2020 to December 2022. The median follow-up was 17 months. In all patients, radiation \u0000therapy was carried out in combination with neoadjuvant, concomitant and adjuvant hormone therapy \u0000with analogues of luteinizing hormone releasing hormone. All patients received a course of radiation \u0000therapy without interruption. At the time of analysis, all patients are alive and stay by under active surveillance with no signs of progression. At the end of radiation therapy, all patients noted manifestations \u0000of toxicity of the I-II degree genitourinary and gastrointestinal systems. There is a gradual recovery of \u0000patients in the form of a decrease and relief of radiation reactions in 3-6 months after the end of radiation therapy. \u0000Conclusion: The first data evaluating the safety of the new developed method of radiation therapy by \u0000hypofraction mode with additional prophylactic irradiation of the retroperitoneal lymph nodes demonstrate good tolerability. However, further study and conducting the 3rd phase of randomized trial are required to determine clinical efficacy.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117203637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simplified Method for Calculation of Internal Exposure Dose to Bone Metastases During Radionuclide Therapy","authors":"B. Narkevich, A. Krylov, A. Ryzhkov","doi":"10.52775/1810-200x-2023-97-1-43-56","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-43-56","url":null,"abstract":"Purpose: Development of a simplified method for calculating internal doses of bone metastases during radionuclide therapy with radiopharmaceuticals. \u0000Material and methods: A comparative analysis of the advantages and disadvantages of 3 existing methods of dosimetry of internal irradiation (MIRD formalism, the method of the dose kernel of a point isotropic source and the Monte Carlo modeling method) was carried out in relation to the task of dosimetry of bone metastases. It has been shown that all of them, having a high accuracy of dose estimation, remain unsuitable for wide clinical practice due to their mathematical complexity, laboriousness, low availability, and overestimated requirements for user qualifications. \u0000A simplified method is proposed for determining doses of internal irradiation of tumor foci based on quantitative data from SPECT/CT scanning of an X-ray phantom and a real patient who has been injected with a b-g-radiating therapeutic radiopharmaceutical. \u0000Results: On a clinical example of radionuclide therapy with 177Lu-PSMA of a patient with stage 4 prostate cancer, dose estimates were obtained for both internal exposure to b-particles and g-quanta from the radiopharmaceutical accumulated in bone foci, and external exposure to g-quanta of the same radiopharmaceutical contained at the time of measurements in the tissues surrounding the focus and environments of the whole body of the patient. Calculations were made for bone metastases of 7 localizations in dynamics for each of the 5 fractions of radionuclide therapy. It is shown that the total focal doses for 5 fractions of internal exposure vary from 70.6 to 116.8 Gy for different foci, which corresponds to the literature data obtained by more accurate methods of dosimetry of internal exposure. \u0000Conclusion: The developed simplified method for obtaining dose estimates for radionuclide therapy of bone metastases is characterized by an accuracy acceptable for clinical purposes while ensuring simplicity and low labor intensity of its practical application by a wide range of medical physicists and radiologists.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114885374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Homogeneous Dose Distribution Inside the Cancer Target on Local Control in Glioblastomas","authors":"A. S. Chuguev, A. Belikova, V. Gerasimov, A. Kaprin, P. Datsenko","doi":"10.52775/1810-200x-2023-97-1-14-20","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-14-20","url":null,"abstract":"Purpose: Assessment of the effect of homogeneous distribution inside the radiation target on local control in glioblastoma. \u0000Material and methods: In patients under the age of 50, fractionation with the prescribed dose of 2 and 3 Gy was alternately used: the first patient was prescribed a regimen with a dose of 3 Gy, the next – with a dose of 2 Gy (a study involving a pairwise selection strategy). The same approach is used for the older age group (50 years and more). A total of 141 patients had morphologically confirmed glioblastoma (grade 4). 10 patients who had not completed a full course of radiation therapy were excluded. Additionally, 27 patients with GBM were added, treated in the experimental study of National Medical Research Radiological Centre without methodological features. In total, 158 patients were included in the study. 74 patients were treated with the prescribed dose of 2 Gy, 84 had a dose of 3 Gy. \u0000Results: The median homogeneity index in our study was 7.5 (95% Cl: 6,7-8,3). The minimum HI indicator was at the level of 2.5, the maximum – 36.9. We managed to identify the most informative level of the homogeneity index according to the criterion of local control. The median disease-free survival in the group with HI>=8.5 was 7.9 months (n=62; 95 % Cl: 1.6-14.2), in the group with a lower level of homogeneity - 5.4 months (n=96; p=0.024). The significance of the highlighted HI range depended on the fractionation mode used. The median relapse–free survival with fractionation of 3 Gy in the group with HI>=8.5 was 12.7 months (n=38), in the group with a lower level of homogeneity - 8.3 months (n=46; p=0.020). In the group with fractionation regime of 2 Gy: 6.4 and 3.8 months, respectively (n=24/50; p=0.336). The median overall survival in the group with HI>=8.5 was 27.2 months, in the group with a lower level of homogeneity – 21.2 months (p=0.904). \u0000Conclusion: The level of homogeneity has no significance according to the criterion of overall survival. Despite the fact that this predictor is of value only in scientific terms, the fact of its influence on local control allows to continue research in this direction. This primarily concerns the fractionation regimen with a prescribed dose of 3 Gy.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121288033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glossary of Terms and Concepts in Medical Radiation Physics. Terminology Used in Dosimetry of Radiation Therapy","authors":"S. Vatnitsky","doi":"10.52775/1810-200x-2023-97-1-67-83","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-67-83","url":null,"abstract":"Medical radiation physics supports medical diagnostic and treatment process based on the use of ionizing radiation in radiation therapy, nuclear medicine, radiation diagnostics and radiation safety of patients and personnel. However, the successful implementation of this process requires close interaction of specialists in all the above areas. The basis of such interaction is the unification of the terminology and concepts used at various stages of the diagnostic and treatment process. The article presents a glossary on dosimetry of radiation therapy which contains the most commonly used terms in this field and explanations for each of them. The glossary is intended for use both in professional education, including postgraduate education, and for medical physicists and radiation oncologists working in radiological medical organizations.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123240053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glossary of Terms and Concepts in Medical Radiation Physics. Terminology Used in Treatment Planning of External Radiation Therapy","authors":"S. Vatnitsky","doi":"10.52775/1810-200x-2023-97-1-84-97","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-84-97","url":null,"abstract":"Medical radiation physics supports medical diagnostic and treatment process based on the use of ionizing radiation in radiation therapy, nuclear medicine, radiation diagnostics and radiation safety of patients and personnel. However, the successful implementation of this process requires close interaction of specialists in all the above areas. The basis of such interaction is the unification of the terminology and concepts used at various stages of the diagnostic and treatment process. The article presents a glossary on treatment planning of external radiation therapy which contains the most commonly used terms in this field and explanations for each of them. The glossary is intended for use both in professional education, including postgraduate education, and for medical physicists and radiation oncologists working in radiological medical organization","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"264 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116167814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ionizing Radiation in PET Center and Level of Their Exposure on Personnel and Patients","authors":"A. Khmelev","doi":"10.52775/1810-200x-2023-97-1-98-109","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-98-109","url":null,"abstract":"CONTENTS \u0000Introduction \u00001. Dose rate of gamma and neutron radiation in the cyclotron facility \u00002. Ionizing radiation in radiochemical laboratory and personnel doses \u00003. Radiation sources in PET department and their contribution in personnel radiation exposure \u00004. Doses of patients under performance of PET/CT study \u0000Summary","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114443853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal Levels of Isoeffective Doses for Two Fractionation Modes in Glioblastoma","authors":"P. Datsenko, A. S. Chuguev, V. Gerasimov, A. Belikova, A. Kaprin","doi":"10.52775/1810-200x-2023-97-1-5-13","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-5-13","url":null,"abstract":"Purpose: Determination of the optimal level of a/b for the calculation of isoeffective doses in glioblastoma. \u0000Material and methods: Two fractionation modes were studied in 141 patients with primary glioblastoma (GBM). Fractionation with the prescribed dose of 2 and 3 Gy was used alternately (a study involving a pairwise selection strategy). In addition, 34 GBM patients treated in the pilot study of the National Medical Research Radiological Centre earlier were added to the database, the total number of patients was 175 people. \u0000Results: As of December 2022, 134 (76.6 %) of 175 treated patients had a fatal outcome. In the range of values of the coefficient a/b from 5.0 to 10.0, the indicator a/b=7.5 turned out to be the most informative. According to the criterion of overall survival, a favorable level of isoeffective dose exceeds 59.5 Gy. \u0000The median overall survival in the group with an isoeffective dose of >=59.5 Gy was 22.3 months (95 % Cl: 17.7–26.9), in the group with a lower dose level – 10.3 months (p<0.0001). \u0000According to monovariate analysis at an isoeffective dose of >=59.5 Gy for fractionation regimens with a prescribed dose of 2 and 3 Gy, survival rates were almost identical (p=0.745). There were no differences in overall survival in the groups with prescribed doses of 2 and 3 Gy, taking into account the use of temozolomide on the background of radiation therapy (OR=1,087; p=0.677). \u0000In the older age group, a/b= 7.5 should be used to determine the level of isoeffective dose. The median overall survival with an isoeffective dose of >=59.5 Gy was 20.57 months (n=98; 95 % Cl: 17.7–23.4), with a lower dose level – 6.35 months (n=24; p<0.0001). In persons younger than 50 years of age, a decrease in the a/b coefficient should be expected. \u0000Conclusion: From our point of view, the obtained data on the equivalence of regimens with a prescribed dose of 2 and 3 Gy indicate the correct choice of the level of a/b in glioblastoma and the selection of the minimum level of isoeffective dose (59.5 Gy) according to the criterion of overall survival.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125473875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topometric Preparation and Contouring in Radiotherapy Planning Patients after Breast Reconstruction with Syntetic Materials","authors":"E. V. Timoshkina, O. Trofimova, V. Glebovskaya, M. V. Chernich, T. Krylova","doi":"10.52775/1810-200x-2023-97-1-21-32","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-21-32","url":null,"abstract":"Purpose: Set out and substantiate basing on contemporery data and personal experience the key features and nuances of topometric preparation and contouring of the irradiated volumes when planning external beam radiation therapy in breast cancer patients after immediate reconstruction with usage of synthetic materials. \u0000Materials and methods: In terms of this article are outlined the main provisions regarding topometric preparation, the need of expander deflation, the determination of irradiated volumes, and the effects of the metal port of the expander on the dose distribution. \u0000Results: Evidence-based recommendations on the implementation of such stages of the technological chain of external beam radiation therapy, as topometric preparation and contouring of irradiated volumes in patients with breast cancer after immediate reconstruction with synthetic materials, are briefly presented.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115161894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diagnosis of Osteoporosis on Serial X-ray Machines","authors":"N. Rudnev, A. Turinge, V. Nedorezov, A. Fedin, Y. Grishkin","doi":"10.52775/1810-200x-2023-97-1-57-66","DOIUrl":"https://doi.org/10.52775/1810-200x-2023-97-1-57-66","url":null,"abstract":"A method for determining bone density based on a single exposure on a serial X-ray machine and subsequent calibration by a stepped aluminum wedge has been developed. The experimental setup is described, the results of measurement on the phantom are presented. During calibration, an effective subtraction of soft tissues was carried out. The results of comparison of experimental data with GEANT-4 simulation are presented. Estimates of the effect of uneven illumination, coordinate resolution and scattered background on the quality of the image are made. The conclusion is made about the competitiveness of the developed technique in comparison with traditional two-beam diagnostics.","PeriodicalId":222791,"journal":{"name":"Meditsinskaya Fizika","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126276402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}