Iranian Journal of Medical Physics最新文献

{"title":"Feasibility of Megavoltage CT for High-Dose Retrospective Planning of Helical Tomotherapy and Linac Treatment Plans: Hepatocellular Carcinoma Cancer Case","authors":"S. Pawiro, Ahmad Syafi'i, W. Wibowo, N. Nasution, Hendry Kodrat","doi":"10.22038/IJMP.2021.53854.1885","DOIUrl":"https://doi.org/10.22038/IJMP.2021.53854.1885","url":null,"abstract":"Purpose: To investigate the use of megavoltage CT (MVCT) images for retrospective planning in high-dose and low-fractionation radiation techniques for Helical Tomotherapy and Linac. Material and Methods: This work used pre-treatment MVCT images for retrospective planning in high-dose hypofractionation of eight hepatocellular carcinoma (HCC) patients using stereotactic body radiation therapy (SBRT) technique. The dose per fraction was 5.5–8 Gy in 4–5 fractions. As the patients were scanned with HT MVCT before each treatment, the selected MVCT images were registered to KVCT for re-contouring, then the images were exported to HT and Linac for planning. The KVCT scan images were also exported from HT to Linac for planning in Linac. The final plans were compared and analyzed using the following parameters: homogeneity index (HI), conformity index (CI), and organs at risk (OAR) constraints. The dose verification was performed by gamma passing rate (GPR) test using EBT3 films. Results: CI values were found in the range 0.7–1.00 ((CI) : 0.95 ± 0.063), and HI values were found from 0.02 to 0.53 ((HI) : 0.16 ± 0.12). OAR constraints were clinically acceptable. Dose to agreement of 3mm and dose difference of 3% were used as GPR criteria for each plan modality. Conclusions: These results suggest that MVCT could be used as an alternative modality for high-dose re-planning in HT and Linac as well as being used for position verification.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43084097","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":"Biological and dosimetric effect of the number of beams for radiotherapy plans of breast cancer patients. Z. Mansour1, Ehab M. Attalla 2, Ibrahim A. Awad 3 M.I. Abdel Hamid 4 and A. Sarhan 5","authors":"Zezy Mansour, A. Ehab, A. Sarhan, Ebrahim Awad, M. Ismail","doi":"10.22038/IJMP.2021.55487.1919","DOIUrl":"https://doi.org/10.22038/IJMP.2021.55487.1919","url":null,"abstract":"Aim: To evaluate the biologic differences in treatment plans, the dosimetric outcome with different number of beams on 3D conformal radiotherapy for breast cancer patients as well as evaluate the outcome of plans with more number of fields compared with less number of fields for irradiation of breast cancer patients then determine the optimum plan through dosimetric and biological parameters. The study included 13 of the female breast cancer patients who were irradiated, after surgery. The tumor and the organs at risk were delineated. Then for every patient two plans of increasing and decreasing the number of beams were done. The DVH of each plan was analyzed based on the calculating the TCP and NTCP by MATLAB and calculating the dosemetrical parameters such as CI and HI. Results: All the results representing the following parameters V105% , V95% ,V110%, D mean , D max CI, HI and D5% are the same in both more and less number of beams . All the results also showed that the average TCP% of PTV of the plans that contains more numbers of beams is 54.27 % while in other plans 54.65%. Mean± SEM of group (a) is 54.27 ± 1.121 while in group b is 54.65 ± 0.9297 N=13. This show that there is no significance in the group (a) (increasing numbers of beams) versus group (b) (less numbers of beam) means that the tumor control by increasing the number of beams is nearly the same as decreasing the number, b value = ( 0.7964). This occurred in the rest of the parametersRadio oncologist and medical physicist must make a decision about treatment though the accurate values of TCP and NTCP and this achieved via testing plans by MATLAP program not by the number of beams.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48546974","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":"Dosimetric evaluation of IMRT (SS / SW) and VMAT treatment plans for nasopharyngeal cancer","authors":"Rachid Errifai, Youssef Bouzekraoui, F. Bentayeb","doi":"10.22038/IJMP.2021.53524.1879","DOIUrl":"https://doi.org/10.22038/IJMP.2021.53524.1879","url":null,"abstract":"Introduction: Radiotherapy of the sphere ORL is still difficult by the presence of complex geometries and very sensitive organs around the target volume.This weapon has benefited from the advances of the VMAT (Volumetric Modulated Arc Therapy) technique, introduced in 2009, it combines the advantages of dynamic arc therapy techniques with the advantages of conformational radiotherapy techniques with intensity modulation (RCMI) by stationary beams.Materials and Methods: The treatment plans of the 4 patients were compared and treated with SS, SW, and VMAT (6MV X-ray beam). The target volumes were three: PTV 70, PTV 63, and PTV56. The organs at risk delineated were the spinal cord, the brainstem, the parotid gland .The dose was delivered once a day, five days a week and in 35 sessions in Integrated Boost (Simultaneaous Integrated Boost (SIB)), aiming to deliver the prescribed dose to the tumor volume while respecting the dose constraints in the organs at risk and minimizing their degree of toxicity.Results: Similar results were found for target volume coverage (Dmax). The SS technique allowed better parotid sparing, which explains its contribution to limiting late complications such as xerostomia. The VMAT technique allows better protection of the brainstem by reducing about 6 Gy, for the spinal cord the doses received were almost equal. Finally, there is no statistically significant difference between the different techniques.Conclusion: All these results conform the conformational capacities of these innovative techniques from a dosimetric and above all clinical point of view. Their ability to cover the target volumes while largely respecting the constraints on organs at risk.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43308968","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":"A Comparative Dosimetric Study for the Treatment of Left-Sided Breast Cancer using Three-Dimensional Conformal Deep Inspiration Breath-Hold and Free-Breathing Intensity-Modulated Radiotherapy Techniques","authors":"M. Morsy, E. Attalla, W. Attia","doi":"10.22038/IJMP.2020.44451.1681","DOIUrl":"https://doi.org/10.22038/IJMP.2020.44451.1681","url":null,"abstract":"Introduction: Most women with left-sided breast cancer are at an increased risk of heartmorbidity and mortality from the adjuvant radiotherapy due to an increase in heart absorbed dose during radiotherapy treatment. This study aimed to compare free-breathing intensity-modulated radiotherapy (FB-IMRT) and three-dimensional conformal deep inspiration breath-hold (3DCRT-DIBH) techniques in terms of the cardiac dose. Material and Methods: In total, 15 women with left-sided breast cancer underwent FB and DIBH computed tomography (CT) scans in the same supine position. For DIBH CT, 3D-CRT plans were created using two opposing wedged tangential fields and for FB-CT, 4-5 IMRT optimized tangential fields were created. All plans were evaluated using the dose-volume histogram. The data were analyzed in SPSS software version 20 (IBM, IL). Results: The FB-IMRT plans were more homogeneous and had more dose coverage and fewer hotspots, than the 3DCRT-DIBH plans; however, the planning target volume V95% was clinically acceptable for both techniques. Furthermore, the 3DCRT-DIBH plans were much faster and require fewer monitor units. A significantly lower mean dose of heart, left lung, left anterior descending coronary artery, right lung, and V10% left lung were observed in 3DCRT-DIBH plans, compared to FB-IMRT plans. Moreover, FB-IMRT plans showed a significant further dose reduction in heart V25% and V30%. Conclusion: The majority of the patients with left-sided breast cancer who treated with the DIBH technique were getting sufficient benefits of radiotherapy, and DIBH was a comprehensive strategy for reducing cardiac doses during radiotherapy treatment.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":"18 1","pages":"194-202"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48394339","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":"A Quantitative Assessment of Indoor Radon Level and Its Annual Effective Dose in Buildings of Gachin Rural District in Hormozgan Province, Iran","authors":"Ali Jamjour, G. Haddadi, M. Haghani, Mohammaad Haghparast, M. Afkhami","doi":"10.22038/IJMP.2020.45461.1706","DOIUrl":"https://doi.org/10.22038/IJMP.2020.45461.1706","url":null,"abstract":"Introduction: Measurement of indoor radon concentration and its determining factors is crucial for improving public health and developing proper methods that can reduce indoor radon concentrations. This study aimed to measure the indoor radon concentration and to examine its variations in relation to variables, such as the construction materials, ventilation, and age of buildings. Material and Methods: Indoor radon concentrations were measured using solid-state nuclear track detectors (SSNTDs) during winter. Each detector was mounted 50-90 cm above the surface flooring of bedrooms and living rooms. After three months of exposure, the detectors were collected and transferred to a laboratory. They were then etched in 6.25 N NaOH solution in a bath at a constant temperature of 90°C for 240 minutes. Next, the detectors were washed with distilled water and dried. The alpha particle tracks were counted using an automatic alpha track counting system. Results: The mean radon concentration was 53.20 Bq/m3,and 94% of the samples had a radon concentration 3, which is the action level proposed by the World Health Organization (WHO). The annual effective dose varied from 0.25 mSvy-1 to 3.05 mSvy-1, with a mean dose of 0.91 mSvy-1. The results showed that the type of constructed materials and ventilation influence the indoor radon concentration in winter. Conclusion: The annual effective dose in the study area was below the global average of 1.15 mSvy-1. Therefore, local residents must be informed about the health risks of high radon concentrations and understand the role of improved ventilation in reducing the indoor radon levels.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":"18 1","pages":"171-177"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49327593","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":"Dosimetric impact of contrast medium on different photon energies using conformal & IMRT techniques in the treatment of carcinoma cervix and its validation with indigenous phantom","authors":"M. Bhushan, D. Tripathi, G. Yadav, L. Kumar, S. Barik, S. Tandon, Pawan Kumar, S. Mitra, M. Gairola","doi":"10.22038/IJMP.2021.54553.1896","DOIUrl":"https://doi.org/10.22038/IJMP.2021.54553.1896","url":null,"abstract":"Introduction Considering the unwanted exposure to organs in path of the beam, 4-field (4F) and subsequently, Intensity-modulated-radiation-therapy (IMRT), is known as standard mode of treatment of carcinoma cervix. It is routine practice to inject intravenous contrast during simulation scan which elopes after that from patient body. Therefore, the impact of contrast media should be investigated for radiation dose calculations.Material & MethodsAn indigenously made phantom, named as ‘original contrast (OC)’, was used with dimensions 15 x 15 x 30 cm3. A sleeve was given to place the ionization chamber at the isocentre of the planning target volume (PTV) inside the cylindrical vial of iodinized contrast. Similarly, a virtual phantom was created with similar dimensions in presence and absence of contrast media, called as ‘virtual contrast (VC)’ and ‘virtual without contrast (VWC)’ phantom. Plans were generated with photon energies (6MV/10MV/15MV/6FFF/10FFF) using 4F and IMRT technique. Plans were evaluated for PTV (D99%, D10%, Dmean) and Bladder & Rectum (V30Gy, V10Gy). Normal-tissue-integral-dose (NTID) and total-monitor-units (TMU) were also evaluated.Results D99% of the PTV was comparable in VC and VWC phantoms but was decreased for OC phantom. Similarly, D10% was reportedly higher as 54.03 Gy (4F, 6 MV), 54.71 Gy (4F, 15 MV), 55.78 Gy (4F, 6 FFF) and 57.64 Gy (4F, 10 FFF) for OC phantom. D30% of the bladder and also the NTID was lesser for IMRT cases in all the selected phantoms. Additionally, 4F has shown lesser spillage with 6MV/15 MV photon beam energies in OC phantom. The ‘total monitor units (TMU)’ required for IMRT plans were significantly higher.ConclusionThe contrast material under-estimate the planned dose yet has insignificant influence on the dose calculation. Therefore, unnecessary exposure of dual scans should be avoided and use of 6MV and IMRT technique should be continued in the clinics.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45839482","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":"The role of Crocetin-loaded PLGA Nanoparticles as a Pre-treatment agent on Indocyanine-photodynamic therapy of breast cancer cells","authors":"A. Sazgarnia, Samaneh Soudmand Salarabadi, M. Hashemi","doi":"10.22038/IJMP.2021.56373.1942","DOIUrl":"https://doi.org/10.22038/IJMP.2021.56373.1942","url":null,"abstract":"Objectives: Photodynamic therapy (PDT) can be considered as a non-invasive method for cancer treatment. One of the most commonly used photosensitizer (PS) is Indocyanine Green (ICG), a water-soluble dye with high penetration depth. However, high ‎cytotoxicity in high concentration and instability in aqueous media were limited its application. ‎It was shown that using nanoparticles or plant extracts in combination with PS could improve PDT efficiency. In this study, anti-cancer properties of crocetin (Crt) loaded PLGA (Poly lactic-co-glycolic acid) nanoparticles (NPs) were utilized to increase the PDT efficacy with ICG on the MCF-7 cells. Materials and Methods: Crt was encapsulated into PLGA NPs and its particle size distribution and encapsulation efficiency were evaluated. IC10 of Crt, PLGA-Crt NPs and ICG was determined by MTT assay in MCF-7 cancer cells. At these concentrations, the cells were pre-treated with Crt or PLG-Crt, then treated with ICG and finally exposure to near infrared (NIR) laser with 2.5 W powers at different times. The cells viability was evaluated by the MTT assay.Results: The findings showed no dark cytotoxicity due to ICG (12.9 μM), Crt or PLGA-Crt alone. But NIR laser irradiation in the presence of ICG after cells pre-treatment by the Crt or PLGA-Crt NPs leads to induce cell death to (61.6 ±7) % and (75.5 ±5) %, respectively. Conclusion: The results demonstrated that PLGA-Crt NPs in combination with ICG could improve PDT outcomes more efficiently in comparison with Crt and ICG. Therefore, this method could be effective in breast cancer therapy with low cytotoxicity.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43536963","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":"Lifetime Cancer Risk Due to Alpha Emitters in Water Samples for Some Marshes in Dhi-Qar Governorate, Iraq","authors":"A. Abojassim, Awsam Abdulsattar Marzaali, Mohamed Al-Shreefi","doi":"10.22038/IJMP.2021.53498.1878","DOIUrl":"https://doi.org/10.22038/IJMP.2021.53498.1878","url":null,"abstract":"Abstract Background: Radon (222Rn), radium (226Ra), and uranium (238U) concentrations in the samples of marshes’ water have been measured. The samples were collected from various places at the marshes, in Dhi-Qar governorate. Also, the annual effective dose (AED), with lifetime cancer risk due to ingestion of 222Rn and 226Ra in drinking water were calculated. Materials and Methods: Solid State Nuclear Tracks Detectors (SSNTD ) type CR-39 in present study was used. Results: The average values of 222Rn, 226Ra and uranium 238U concentration in water samples were found to be 0.282±0.03 Bq/l, 0.46±0.05 Bq/l, and 0.59±0.08 mg/kg respectively. The average values of AED caused by ingestion of 222Rn and 226Ra in the samples of the study were found to be 0.018±0.002 mSv/y and, 0.091±0.012 mSv/y, respectively. The average values of total AED and lifetime cancer risk values were calculated to be 0.11±0.01 mSv/y and (4.26±0.60)×10-4, respectively. Conclusions: The average concentration values of 222Rn and 226Ra were found to be within the global average limitations (0.4 Bq/l), and (1 Bq/l) that are recommended by World Health Organization (WHO) 1993 and 2011, while the average of 238U concentrations were within the global average limitation (0.566 mg/kg) that was recommended by Environmental Protection Agency \"EPA\". When some results of AED due to 222Rn and 226Ra concentrations, in the samples under study, were compared with the worldwide median value, that is recommended by WHO 2011; it was found that the lifetime cancer risk in all samples of the present study were higher than the safety limit for the healthy drinking water. Therefore, the water of Marshes that consume in the Dhi-Qar governorate- Iraq, for drinking no healthy.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47376423","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":"Investigation of Radiological Hazards in the Soil of Mazandaran Province, Iran","authors":"S. Kashian, M. S. Kotahi, A. Fathivand, P. Lotfalinezhad","doi":"10.22038/IJMP.2020.43527.1659","DOIUrl":"https://doi.org/10.22038/IJMP.2020.43527.1659","url":null,"abstract":"Introduction: This paper aimed to outline the procedure for determining the activity concentrations of naturally occurring radionuclides (i.e., 226Ra, 232Th, and 40K) in surface soil samples collected from Mazandaran province, Iran. Material and Methods: In total, 61 samples were collected between longitude 50˚ 34′ and 54˚ 10′ east and latitude 35˚ 47′ and 36˚ 35′ north from uncultivated locations of Mazandaran province, Iran. The measurements were performed by the gamma spectrometry system using a High Purity Germanium detector. Results: The mean levels of 226Ra, 232Th, and 40K were found to be 20 Bqkg-1 (without considering high-level areas), 33 Bqkg-1, and 421 Bqkg-1, respectively. The results were compared with those of different countries across the world. The radiological hazard to the natural radioactivity was assessed by calculating the absorbed dose rate, the radium equivalent activity, the external and internal hazard indices, and the outdoor and indoor annual effective dose rate. The mean radium equivalent without considering three high-level areas was estimated at 100.8 Bqkg-1. Conclusion: Results indicated that no radiological risk may threat the residents of the areas under study, except for regions near the hot spring in Sadat Shahr and Lavich, Iran. Without considering high-level areas, the mean radium equivalent activity was 100.8 Bqkg-1 that was about 73% lower than the permissible maximum. Moreover, internal and external hazard indices were less than the unit. The mean absorbed dose rate, as well as the outdoor and indoor annual effective dose rates were 48.56 nGyh-1, 238.4 µSv y-1, and 292.6 µSv y-1, respectively.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":"18 1","pages":"133-138"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48846389","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":"Comparison and Correction of Thermo-Luminescent Responses in Different Neutron Fields","authors":"S. Baradaran, M. Taheri, A. Moslehi","doi":"10.22038/IJMP.2020.44660.1689","DOIUrl":"https://doi.org/10.22038/IJMP.2020.44660.1689","url":null,"abstract":"Introduction: Neutron dosimetry is a challenging subject in radiation protection. Responses of neutron dosimeters mostly depend on the neutron energy spectrum. Dosimeter response corresponding to a dose-equivalent in the calibration field is different from responses in other neutron fields. Consequently, the dose estimated by neutron dosimeters may be associated with great uncertainty. Therefore, the present study aimed to modify the response in different neutron fields in order to reduce this uncertainty. \u0000Material and Methods: Thermo-luminescent dosimeters (TLDs) are widely used to determine neutron dose-equivalent. In the present study, a set of TLD-600 and TLD-700 dosimeters included in a TLD card was utilized to determine the response to “fast” neutrons of 241Am-Be,252Cf, and 239Pu-Be standard fields in four dose-equivalents of 5, 10, 15, and 20 mSv. Meanwhile, 241Am-Be was regarded as the calibration field.  \u0000Results: As evidenced by the obtained results, for equal dose-equivalents, the original responses in 252Cf and 239Pu-Be fields are smaller, compared to those in the 241Am-Be filed. The maximum discrepancies were obtained at 26.8% and 42.5% occurring at 20 and 5 mSv, respectively. After the application of a correction factor equal to the average of relative responses (i.e., in 241Am-Be to two other fields) corresponding to all dose-equivalents considered, these differences reduced to 12.4% and 21.7%. \u0000Conclusion: It can be concluded that the correction method used in the present study could enhance the accuracy of dose estimated by TLDs in fast neutron fields.","PeriodicalId":14613,"journal":{"name":"Iranian Journal of Medical Physics","volume":"18 1","pages":"84-88"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44770131","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}