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K E R, Krishnan M. Surface dose measurement and comparison between TLD and OSLD during modified re constructive mastectomy irradiation. Biomed Phys Eng Express 2024; 10:045025. [PMID: 38714180 DOI: 10.1088/2057-1976/ad47fd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 05/07/2024] [Indexed: 05/09/2024]
Abstract
Radiotherapy (RT) is one of the major treatment modalities among surgery and chemotherapy for carcinoma breast. The surface dose study of modified reconstructive constructive Mastectomy (MRM) breast is important due to the heterogeneity in the body contour and the conventional treatment angle to save the lungs and heart from the radiation. These angular entries of radiation beam cause an unpredictable dose deposition on the body surface, which has to be monitored. Thermoluminescent dosimeter (TLD) or optically stimulated luminescent dosimeter (nano OSLD) are commonly preferable dosimeters for this purpose. The surface dose response of TLD and nano OSLD during MRM irradiation has been compared with the predicted dose from the treatment planning system (TPS). The study monitored 100 MRM patients by employing a total 500 dosimeters consisting of TLD (n = 250) and nano OSLD (n = 250), during irradiation from an Elekta Versa HD 6 MV Linear accelerator. The study observed a variance of 3.9% in the dose measurements for TLD and 3.2% for nano OSLD from the planned surface dose, with a median percentage dose of 44.02 for nano OSLD and 40.30 for TLD (p value 0.01). There was no discernible evidence of variation in dose measurements attributable to differences in field size or from patient to patient. Additionally, no variation was observed in dose measurements when comparing the placement of the dosimeter from central to off-centre positions. In comparison, a minor difference in dose measurements were noted between TLD and nano OSLD, The study's outcomes support the applicability of both TLD and nano OSLD as effective dosimeters during MRM breast irradiation for surface dose evaluation.
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Affiliation(s)
- Ratheesh K E
- Department of Medical Physics, Centre for Interdisciplinary Research, D. Y. Patil Education Society (Deemed to be University), Kolhapur, Maharashtra, India
| | - Mayakannan Krishnan
- Department of Medical Physics, Centre for Interdisciplinary Research, D. Y. Patil Education Society (Deemed to be University), Kolhapur, Maharashtra, India
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McCluskey SM, Muyindike WR, Nanfuka V, Omoding D, Komukama N, Barigye IT, Kansiime L, Tumusiime J, Aung TN, Stuckwisch A, Hedt-Gauthier B, Marconi VC, Moosa MYS, Pillay D, Giandhari J, Lessells R, Gupta RK, Siedner MJ. Population Effectiveness of Dolutegravir Implementation in Uganda - A Prospective Observational Cohort Study (DISCO): 48-week Results. J Infect Dis 2024:jiae260. [PMID: 38748986 DOI: 10.1093/infdis/jiae260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 04/30/2024] [Accepted: 05/10/2024] [Indexed: 05/18/2024] Open
Abstract
BACKGROUND Tenofovir/lamivudine/dolutegravir (TLD) is the preferred first-line antiretroviral therapy (ART) regimen for people with HIV (PWH), including those who were previously virologically suppressed on non-nucleoside reverse transcriptase inhibitors (NNRTIs). We sought to estimate the real-world effectiveness of the TLD transition in Ugandan public-sector clinics. METHODS We conducted a prospective cohort study of PWH ≥18 years who were transitioned from NNRTI-based ART to TLD. Study visits were conducted on the day of TLD transition and 24- and 48- weeks later. The primary endpoint was viral suppression (<200 copies/mL) at 48-weeks. We collected blood for retrospective viral load (VL) assessment and conducted genotypic resistance tests for specimens with VL >500 copies/mL. RESULTS We enrolled 500 participants (median age of 47 years; 41% women). At 48-weeks after TLD transition, 94% of participants were in care with a VL <200 copies/mL (n = 469/500); 2% (n = 11/500) were lost from care or died; and only 2% (n = 9/500) had a VL >500 copies/mL. No incident resistance to DTG was identified. Few participants (2%, n = 9/500) discontinued TLD due to adverse events. CONCLUSIONS High rates of viral suppression, high tolerability, and lack of emergent drug resistance support use of TLD as the preferred first-line regimen in the region.
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Affiliation(s)
- Suzanne M McCluskey
- Medical Practice Evaluation Center, Massachusetts General Hospital, Boston, MA, USA
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | | | | | - Daniel Omoding
- Mbarara University of Science and Technology, Mbarara, Uganda
| | | | - Ian T Barigye
- Mbarara University of Science and Technology, Mbarara, Uganda
| | - Lydia Kansiime
- Mbarara University of Science and Technology, Mbarara, Uganda
| | | | - Taing N Aung
- Medical Practice Evaluation Center, Massachusetts General Hospital, Boston, MA, USA
| | - Ashley Stuckwisch
- Medical Practice Evaluation Center, Massachusetts General Hospital, Boston, MA, USA
| | - Bethany Hedt-Gauthier
- Harvard Medical School, Boston, MA, USA
- Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Vincent C Marconi
- Emory University School of Medicine and Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Mahomed-Yunus S Moosa
- Department of Infectious Diseases, University of KwaZulu-Natal, Durban, South Africa
| | | | - Jennifer Giandhari
- KwaZulu-Natal Research Innovation and Sequencing Platform, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Richard Lessells
- Department of Infectious Diseases, University of KwaZulu-Natal, Durban, South Africa
| | - Ravindra K Gupta
- University of Cambridge, Cambridge, United Kingdom
- Africa Health Research Institute, Durban, South Africa
| | - Mark J Siedner
- Medical Practice Evaluation Center, Massachusetts General Hospital, Boston, MA, USA
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- Africa Health Research Institute, Durban, South Africa
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Mehrara E. Thermoluminescence dosimetry ( TLD) in a 3 T magnetic resonance imaging (MRI) environment: implications for personnel exposure monitoring. Biomed Phys Eng Express 2024. [PMID: 38701767 DOI: 10.1088/2057-1976/ad470c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
Thermoluminescent dosimeters (TLDs) serve as compact and user-friendly tools for various applications, including personal radiation dosimetry and radiation therapy. This study explores the potential of utilizing TLD-100 personal dosimetry, conventionally applied in PET/CT (positron emission tomography/computed tomography) settings, in the PET/MRI (magnetic resonance imaging) environment. The integration of MRI into conventional radiotherapy and PET systems necessitates ionizing radiation dosimetry in the presence of static magnetic fields. In this study, TLD-100 dosimeters were exposed on the surface of a water-filled cylindrical phantom containing PET-radioisotope and positioned on the patient table of a 3 T PET/MRI, where the magnetic field strength is around 0.2 T, aiming to replicate real-world scenarios experienced by personnel in PET/MRI environments. . Results indicate that the modified MR-safe TLD-100 personal dosimeters exhibit no significant impact from the static magnetic field of the 3 T PET/MRI, supporting their suitability for personal dosimetry in PET/MRI settings. This study addresses a notable gap in existing literature on the effect of MRI static magnetic field on TLDs.
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Affiliation(s)
- Esmaeil Mehrara
- University of Gothenburg, Sahlgrenska (SU), klinfys-NM, Bla straket 5, malpunk G, plan 1A, Goteborg, Vastra Gotaland, 41345, SWEDEN
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Marulli G, Moutinho C. Experimental Testing on Tuned Liquid Dampers for Implementation in Industrial Chimneys. Sensors (Basel) 2024; 24:2800. [PMID: 38732906 PMCID: PMC11086212 DOI: 10.3390/s24092800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/22/2024] [Accepted: 04/25/2024] [Indexed: 05/13/2024]
Abstract
A TLD is a passive damping device that works by dissipating energy through the sloshing of the liquid and the effect of wave breaking, thereby controlling the vibrations of the structure. One of the applications where TLDs are of great interest is in the case of industrial chimneys since these structures often have a very low natural frequency, which can be easily achieved in a control device of this type. The main objective of this study is to evaluate the behaviour of an annular TLD composed of multiple cells through laboratory tests and investigate if it is adequate to design it as an agglomeration of smaller rectangular TLDs. The influence of the amplitude of displacement on the behaviour of the annular TLD will also be analysed. The tests were performed on a shaking table and recurring with pendulums of the same length but of different masses. Three reservoirs were studied as TLDs: a rectangular one, a cell of an annular TLD and a quarter-ring of an annular TLD. This study concluded that the analytical methods developed in previous studies were, in general, adequate for the design of a rectangular TLD and that it was reasonable to design the annular TLD studied as a combination of rectangular ones, as its cells were a close match to a rectangle of similar dimensions. It was also concluded that a compartmentalised annular TLD is an adequate solution for the vibration control of structures with high displacements.
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Affiliation(s)
- Giancarlo Marulli
- CONSTRUCT, ViBest, Faculty of Engineering (FEUP), University of Porto, R. Dr. Roberto Frias S/N, 4200-465 Porto, Portugal;
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Liu K, Velasquez B, Schüler E. Technical note: High-dose and ultra-high dose rate (UHDR) evaluation of Al 2 O 3 :C optically stimulated luminescent dosimeter nanoDots and powdered LiF:Mg,Ti thermoluminescent dosimeters for radiation therapy applications. Med Phys 2024; 51:2311-2319. [PMID: 37991111 PMCID: PMC10939935 DOI: 10.1002/mp.16832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 09/11/2023] [Accepted: 10/25/2023] [Indexed: 11/23/2023] Open
Abstract
BACKGROUND Dosimetry in ultra-high dose rate (UHDR) electron beamlines poses a significant challenge owing to the limited usability of standard dosimeters in high dose and high dose-per-pulse (DPP) applications. PURPOSE In this study, Al2 O3 :C nanoDot optically stimulated luminescent dosimeters (OSLDs), single-use powder-based LiF:Mg,Ti thermoluminescent dosimeters (TLDs), and Gafchromic EBT3 film were evaluated at extended dose ranges (up to 40 Gy) in conventional dose rate (CONV) and UHDR beamlines to determine their usability for calibration and dose verification in the setting of FLASH radiation therapy. METHODS OSLDs and TLDs were evaluated against established dose-rate-independent Gafchromic EBT3 film with regard to the potential influence of mean dose rate, instantaneous dose rate, and DPP on signal response. The dosimeters were irradiated at CONV or UHDR conditions on a 9-MeV electron beam. Under UHDR conditions, different settings of pulse repetition frequency (PRF), pulse width (PW), and pulse amplitude were used to characterize the individual dosimeters' response in order to isolate their potential dependencies on dose, dose rate, and DPP. RESULTS The OSLDs, TLDs, and Gafchromic EBT3 film were found to be suitable at a dose range of up to 40 Gy without any indication of saturation in signal. The response of OSLDs and TLDs in UHDR conditions were found to be independent of mean dose rate (up to 1440 Gy/s), instantaneous dose rate (up to 2 MGy/s), and DPP (up to 7 Gy), with uncertainties on par with nominal values established in CONV beamlines (± 4%). In cross-comparing the response of OSLDs, TLDs and Gafchromic film at dose rates of 0.18-245 Gy/s, the coefficient of variation or relative standard deviation in the measured dose between the three dosimeters (inter-dosimeter comparison) was found to be within 2%. CONCLUSIONS We demonstrated the dynamic range of OSLDs, TLDs, and Gafchromic film to be suitable up to 40 Gy, and we developed a protocol that can be used to accurately translate the measured signal in each respective dosimeter to dose. OSLDs and powdered TLDs were shown to be viable for dosimetric measurement in UHDR beamlines, providing dose measurements with accuracies on par with Gafchromic EBT3 film and their concurrent use demonstrating a means for redundant dosimetry in UHDR conditions.
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Affiliation(s)
- Kevin Liu
- Division of Radiation Oncology, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, Houston, Texas, USA
| | - Brett Velasquez
- Division of Radiation Oncology, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Emil Schüler
- Division of Radiation Oncology, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, Houston, Texas, USA
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Akyea-Larbi KO, Hasford F, Inkoom S, Tetteh MA, Gyekye PK. Evaluation of organ and effective doses using anthropomorphic phantom: A comparison between experimental measurement and a commercial dose calculator. Radiography (Lond) 2024; 30:1-5. [PMID: 37864985 DOI: 10.1016/j.radi.2023.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 10/23/2023]
Abstract
INTRODUCTION The aim of this study was to experimentally measure organ doses for computed tomography (CT) procedures using thermoluminescence dosimeters (TLDs) on a RANDO anthropomorphic phantom and verify the measured doses using CT-Expo software. METHODS The phantom was irradiated using clinical CT scan protocols routinely used for specific procedures in the radiology department. Fifty TLD chips were used in this study. The scanning parameters (kVp, mA, s) used to scan the phantom were used as input parameters for CT-Expo dose estimations. RESULTS The TLD measured organ doses varied between 3.97 mGy for the esophagus and 56.22 mGy for the brain. High doses were recorded in the brain (37.80-56.22 mGy) and the eye lens (29.94-36.16 mGy). Comparing the organ dose measurements between TLD and CT-Expo, the maximum organ dose difference was obtained for the eye lens. A comparison between the two methods for the other organs were all less than 32 %. The effective doses from the TLD measurements for the head, chest, and abdominopelvic CT examinations were 2.78, 6.67, and 17 mSv, respectively and CT-Expo were 2.20, 10.30, and 16.70 mSv, respectively. CONCLUSION The experimental and computational results are comparable, and the reliability of the TLD measurements and CT-Expo dose calculator has been proven. IMPLICATIONS FOR STUDY A reason for the difference in dose measurements between the two methods has been attributed to the dissimilarity in the organ position in the Rando anthropomorphic phantom and the standard mathematical phantom used by CT-Expo. The experimental and computational results have been found to be comparable.
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Affiliation(s)
- K O Akyea-Larbi
- Department of Medical Physics, School of Nuclear and Allied Sciences, University of Ghana, Accra, Ghana; Radiation Protection Institute, Ghana Atomic Energy Commission, Accra, Ghana.
| | - F Hasford
- Department of Medical Physics, School of Nuclear and Allied Sciences, University of Ghana, Accra, Ghana; Radiological and Medical Sciences Research Institute, Ghana Atomic Energy Commission Accra, Ghana
| | - S Inkoom
- Department of Medical Physics, School of Nuclear and Allied Sciences, University of Ghana, Accra, Ghana; Radiation Protection Institute, Ghana Atomic Energy Commission, Accra, Ghana
| | - M A Tetteh
- Department of Medical Physics, School of Nuclear and Allied Sciences, University of Ghana, Accra, Ghana; Radiology Department, Akershus University Hospital, Oslo, Norway
| | - P K Gyekye
- Department of Medical Physics, School of Nuclear and Allied Sciences, University of Ghana, Accra, Ghana; Radiological and Non-Ionizing Directorate, Nuclear Regulatory Authority, Accra, Ghana
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Takahashi LC, Squair PL, Santos TDO, Passos RG. Instrumentation for measuring equivalent ambient dose in urban buildings using TLDs. Appl Radiat Isot 2023; 202:111037. [PMID: 37782981 DOI: 10.1016/j.apradiso.2023.111037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 08/27/2023] [Accepted: 09/21/2023] [Indexed: 10/04/2023]
Abstract
The Thermoluminescent dosimeter is a solid material used as instrumentation for environmental monitoring through determining environmental equivalent dose H∗(10). This work presents the calibration methodology for TLDs LiF:Mg, Cu, P dosimeters and their application to measure H∗(10) in internal buildings occupied by inhabitants of an urban area. The calibration factor and type tests were made according to ISO 4037-3 and IEC 62387, and the uncertainty was determined. The values found are under the reference values. Therefore, the dosimeters can be applied.
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Affiliation(s)
- Laura Cardoso Takahashi
- National Nuclear Energy Commission (CNEN), Nuclear Technology Development Center (CDTN), Belo Horizonte, 6627, 31270-901, Brazil.
| | - Peterson Lima Squair
- National Nuclear Energy Commission (CNEN), Nuclear Technology Development Center (CDTN), Belo Horizonte, 6627, 31270-901, Brazil
| | - Talita de Oliveira Santos
- National Nuclear Energy Commission (CNEN), Nuclear Technology Development Center (CDTN), Belo Horizonte, 6627, 31270-901, Brazil; Federal University of Minas Gerais (UFMG), Belo Horizonte, 190, 30130-100, Brazil
| | - Ricardo Gomes Passos
- National Nuclear Energy Commission (CNEN), Nuclear Technology Development Center (CDTN), Belo Horizonte, 6627, 31270-901, Brazil
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Bahonar BM, Changizi V, Ebrahiminia A, Baradaran S. Prediction of breast dose in chest CT examinations using adaptive neuro-fuzzy inference system (ANFIS). Phys Eng Sci Med 2023; 46:1071-1080. [PMID: 37245194 PMCID: PMC10225119 DOI: 10.1007/s13246-023-01276-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 05/05/2023] [Indexed: 05/29/2023]
Abstract
In chest computed tomography (CT), the breasts located within the scan range receive a substantial radiation dose. Due to the risk of breast-related carcinogenesis, analyzing the breast dose for justification of CT examinations seems necessary. The main goal of this study is to overcome the limitations of conventional dosimetry methods, such as thermoluminescent dosimeters (TLDs) by introducing the adaptive neuro-fuzzy inference system (ANFIS) approach. In this study, the breast dose of 50 adult female patients who underwent chest CT examinations was measured directly by TLDs. Then, the ANFIS model was developed with four inputs including dose length product (DLP), volumetric CT dose index (CTDIvol), total mAs, and size-specific dose estimate (SSDE), and one output (TLD dose). Additionally, multiple linear regression (MLR) as a traditional prediction model was used for linear modeling and its results were compared with the ANFIS. The TLD reader results showed that the breast dose value was 12.37 ± 2.46 mGy. Performance indices of the ANFIS model, including root mean square error (RMSE) and correlation coefficient (R), were calculated at 0.172 and 0.93 for the testing dataset, respectively. Also, the ANFIS model had superior performance in predicting the breast dose than the MLR model (R = 0.805). This study demonstrates that the proposed ANFIS model is efficient for patient dose prediction in CT scans. Therefore, intelligence models such as ANFIS are suggested to estimate and optimize patient dose in CT examinations.
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Affiliation(s)
- Bahareh Moradmand Bahonar
- Department of Radiology and Radiotherapy Technology, Tehran University of Medical Sciences, Tehran, Iran
| | - Vahid Changizi
- Department of Radiology and Radiotherapy Technology, Tehran University of Medical Sciences, Tehran, Iran.
| | - Ali Ebrahiminia
- Department of Medical Physics, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
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Fokam J, Chenwi CA, Takou D, Santoro MM, Tala V, Teto G, Beloumou G, Semengue ENJ, Dambaya B, Djupsa S, Kembou E, Bouba NP, Ajeh R, Cappelli G, Mbanya D, Colizzi V, Ceccherini-Silberstein F, Perno CF, Ndjolo A. Laboratory Based Surveillance of HIV-1 Acquired Drug Resistance in Cameroon: Implications for Use of Tenofovir-Lamivudine-Dolutegravir ( TLD) as Second- or Third-Line Regimens. Viruses 2023; 15:1683. [PMID: 37632026 PMCID: PMC10459610 DOI: 10.3390/v15081683] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/01/2023] [Accepted: 06/13/2023] [Indexed: 08/27/2023] Open
Abstract
Increased HIV drug resistance (HIVDR) with antiretroviral therapy (ART) rollout may jeopardize therapeutic options, especially in this era of transition to fixed-dose tenofovir-lamivudine-dolutegravir (TLD). We studied acquired HIVDR (ADR) patterns and describe potentially active drugs after first- and second-line failure in resource-limited settings (RLS) like Cameroon. A laboratory-based study with 759 patients (≥15 years) experiencing virological failure was carried out at the Chantal Biya International Reference Centre (CIRCB), Yaoundé, Cameroon. Socio-demographic, therapeutic and immunovirological data from patient records were analysed according to HIV-1 genotypic profiles. Median (IQR) ART-duration was 63 (50-308) months. Median CD4 and viremia were 153 (IQR:50-308) cells/mm3 and 138,666 (IQR:28,979-533,066) copies/mL, respectively. Overall ADR was high (93.4% first-line; 92.9%-second-line). TDF, potentially active in 35.7% of participants after first-line and 45.1% after second-line, suggested sub-optimal TLD-efficacy in second-line (64.3%) and third-line (54.9%). All PI/r preserved high efficacy after first-line failure while only DRV/r preserved high-level efficacy (87.9%) after second-line failure. In this resource-limited setting (RLS), ADR is high in ART-failing patients. PI/r strategies remain potent backbones for second-line ART, while only DRV/r remains very potent despite second-line failure. Though TLD use would be preferable, blind use for second- and third-line regimens may be sub-optimal (functional monotherapy with dolutegravir) with high risk of further failure, thus suggesting strategies for selective ART switch to TLD in failing patients in RLS.
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Affiliation(s)
- Joseph Fokam
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
- Faculty of Medicine and Biomedical Sciences (FMBS), University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
- National HIV Drug Resistance Working Group (HIVDRWG), Ministry of Public Health, Yaoundé P.O. Box 3038, Cameroon
- Faculty of Health Sciences, University of Buea, Buea P.O. Box 063, Cameroon
| | - Collins Ambe Chenwi
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
- Faculty of Medicine and Biomedical Sciences (FMBS), University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Desire Takou
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
| | - Maria Mercedes Santoro
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Valere Tala
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
- Faculty of Medicine and Biomedical Sciences (FMBS), University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
| | - George Teto
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
| | - Grace Beloumou
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
| | - Ezechiel Ngoufack Jagni Semengue
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Beatrice Dambaya
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
| | - Sandrine Djupsa
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
| | - Etienne Kembou
- World Health Organisation, Country Office, Yaoundé P.O. Box 155, Cameroon;
| | - Nounouce Pamen Bouba
- Department of Disease, Epidemic and Pandemic Control, Ministry of Public Health, Yaoundé P.O. Box 3038, Cameroon
| | - Rogers Ajeh
- Central Technical Group, National AIDS Control Committee, Yaoundé P.O. Box 2005, Cameroon
| | - Giulia Cappelli
- Italian National Research Council, P. le Aldo Moro, 7, 00185 Rome, Italy
| | - Dora Mbanya
- Faculty of Medicine and Biomedical Sciences (FMBS), University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
- National Blood Transfusion Service, Ministry of Public Health, Yaoundé P.O. Box 3038, Cameroon
- Haematology and Transfusion Service, Centre Hospitalier et Universitaire (CHU), Yaounde-13, Yaoundé P.O Box 30335, Cameroon
| | - Vittorio Colizzi
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Francesca Ceccherini-Silberstein
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Carlo-Federico Perno
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
- Bambino Gesu’ Children’s Research Hospital, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Alexis Ndjolo
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Prevention and Management (CIRCB), Messa, Yaoundé P.O. Box 3077, Cameroon; (D.T.)
- Faculty of Medicine and Biomedical Sciences (FMBS), University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
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Matusiak K, Wolna J, Jung A, Sadowski L, Pawlus J. Impact of the Frequency and Type of Procedures Performed in Nuclear Medicine Units on the Expected Radiological Hazard. Int J Environ Res Public Health 2023; 20:5206. [PMID: 36982115 PMCID: PMC10049529 DOI: 10.3390/ijerph20065206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/11/2023] [Accepted: 03/14/2023] [Indexed: 06/18/2023]
Abstract
Nuclear medicine procedures play an important role in medical diagnostics and therapy. They are related to the use of ionizing radiation, which affects the radiological exposure of all of the persons involved in their performance. The goal of the study was to estimate the doses associated with the performance of various nuclear medicine procedures in order to optimize workload management. The analysis was performed for 158 myocardial perfusion scintigraphy procedures, 24 bone scintigraphies, 9 thyroid scintigraphies (6 with use of 131I and 3 with 99mTc), 5 parathyroid glands and 5 renal scintigraphies. In this evaluation, two possible locations of thermoluminescent detectors, used for measurements, were taken into consideration: in the control room and directly next to the patient. It was shown how the radiological exposure varies depending on the performed procedure. For high activity procedures, ambient dose equivalent registered in the control room reached the level over 50% of allowed dose limit. For example, ambient dose equivalent obtained in control room when performing bone scintigraphy only was 1.13 ± 0.3 mSv. It is 68% of calculated dose limit in the examined time span. It has been shown that risk associated with nuclear medicine procedures is influenced not only by the type of procedure, but also by the frequency of their performance and compliance with the ALARA principle. Myocardial perfusion scintigraphy accounted for 79% of all evaluated procedures. The use of radiation shielding reduced the obtained doses from 14.7 ± 2.1 mSv in patient's vicinity to 1.47 ± 0.6 mSv behind the shielding. By comparing the results obtained for procedures and dose limits established by Polish Ministry of Health, it is possible to estimate what should be the optimal division of duties between staff, so that everyone receives similar doses.
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Affiliation(s)
- Katarzyna Matusiak
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Av. Mickiewicza 30, 30-059 Krakow, Poland
| | - Justyna Wolna
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Av. Mickiewicza 30, 30-059 Krakow, Poland
| | - Aleksandra Jung
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Av. Mickiewicza 30, 30-059 Krakow, Poland
| | - Leszek Sadowski
- Department of Nuclear Medicine, 5th Military Hospital, ul. Wroclawska 1-3, 30-901 Krakow, Poland
| | - Jolanta Pawlus
- Department of Nuclear Medicine, 5th Military Hospital, ul. Wroclawska 1-3, 30-901 Krakow, Poland
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Johary YH, Albarakati S, AlSohaim A, Aamry A, Aamri H, Tamam N, Salah H, Tahir D, Alkhorayef M, Sulieman A, Bradley D. Evaluation occupationally radiation exposure during diagnostic imaging examinations. Appl Radiat Isot 2023; 193:110648. [PMID: 36669265 DOI: 10.1016/j.apradiso.2023.110648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 12/17/2022] [Accepted: 01/02/2023] [Indexed: 01/09/2023]
Abstract
Occupational radiation exposure can occur due to various human activities, including the use of radiation in medicine. Occupationally exposed personnel surpassing 7.4 millions, and respresent the biggest single group of employees who are exposed to artificial radiation sources at work. This study compares the occupational radiation dose levels for 145 workers in four different hospitals located in the Aseer region in Saudi Arabia. The occupational exposure was quantified using thermoluminescence dosimeters (TLD-100). The levels of annual occupational exposures in targeted hospitals were calculated and compared with the levels of the international atomic energy agency (IAEA) Safety Standards. An average yearly cumulative dose for the two consecutive years. The average, highest and lowest resulted occupational doses under examination in this work is 1.42, 3.9 mSv and 0.72 for workers in various diagnostic radiology procedures. The resulted annual effective dose were within the IAEA approved yearly dose limit for occupational exposure of workers over 18, which is 20 mSv. Staff should be monitored on a regular basis, according to current practice, because their annual exposure may surpass 15% of the annual effective doses.
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Affiliation(s)
- Yehia H Johary
- Radiation Protection Department, General Directorate of Health Affairs in Aseer Region, Abha, Saudi Arabia
| | - Sultan Albarakati
- Radiation Protection Department, General Directorate of Health Affairs in Aseer Region, Abha, Saudi Arabia
| | - Abdullah AlSohaim
- Radiation Protection Department, General Directorate of Health Affairs in Aseer Region, Abha, Saudi Arabia
| | - Ali Aamry
- Medical Imaging Administration, King Saud Medical City, Riyadh, Saudi Arabia.
| | - Hussin Aamri
- Medical Physics Department, King Saud University Medical City (KSUMC), Riyadh, Saudi Arabia
| | - N Tamam
- Department of Physics, College of Science, Princess Nourah Bint Abdulrahman University, P.O Box 84428, Riyadh, 11671, Saudi Arabia
| | - Hassan Salah
- INAYA Medical Collage, Nuclear Medicine Department, Riyadh, Saudi Arabia
| | - Dahlang Tahir
- Department of Physics, Hasanuddin University, Makassar, 90245, Indonesia
| | - Mohammed Alkhorayef
- Department of Radiological Sciences, College of Applied Medical Sciences, King Saud University, P.O Box 10219, Riyadh, 11433, Saudi Arabia
| | - Abdelmoneim Sulieman
- Radiology and Medical Imaging Department, College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, P.O.Box 422, Alkharj, 11942, Saudi Arabia
| | - David Bradley
- Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK; Centre for Applied Physics and Radiation Technologies, School of Engineering and Technology, Sunway University, 47500, Bandar Sunway, Selangor, Malaysia
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12
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Semengue ENJ, Fokam J, Etame NK, Molimbou E, Chenwi CA, Takou D, Mossiang L, Meledie AP, Yagai B, Nka AD, Dambaya B, Teto G, Ka’e AC, Beloumou GA, Djupsa Ndjeyep SC, Abba A, Kengni AMN, Tommo Tchouaket MC, Bouba NP, Billong SC, Sosso SM, Colizzi V, Perno CF, Kouanfack C, Zoung-Kanyi Bissek AC, Eben-Moussi E, Santoro MM, Ceccherini-Silberstein F, Ndjolo A. Dolutegravir-Based Regimen Ensures High Virological Success despite Prior Exposure to Efavirenz-Based First-LINE ART in Cameroon: An Evidence of a Successful Transition Model. Viruses 2022; 15:18. [PMID: 36680058 PMCID: PMC9866637 DOI: 10.3390/v15010018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/07/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
To ensure optimal prescribing practices in the dolutegravir-era in Cameroon, we compared first-line virological response (VR) under tenofovir + lamivudine + dolutegravir (TLD) according to prior exposure to tenofovir + lamivudine + efavirenz (TLE). A facility-based survey was conducted among patients initiating antiretroviral therapy (ART) with TLD (I-TLD) versus those transitioning from TLE to TLD (T-TLD). HIV viral load was performed and unsuppressed participants (VL > 1000 copies/mL) had genotyping performed by Sanger sequencing. Of the 12,093 patients followed, 310 (mean-age: 41 ± 11 years; 52.26% female) complied with study criteria (171 I-TLD vs. 139 T-TLD). The median ART-duration was 14 (12−17) months among I-TLDs versus 28 (24.5−31) months among T-TLDs (15 (11−19) on TLE and 14 (9−15) on TLD), and 83.15% (148/178) were at WHO clinical stages I/II. The viral suppression rate (<1000 copies/mL) was 96.45%, with 97.08% among I-TLDs versus 95.68% among T-TLDs (p = 0.55). VR was similar in I-TLD versus T-TLD at <400 copies/mL (94.15% versus 94.42%) and age, gender, residence, ART-duration, and WHO stages were not associated with VR (p > 0.05). Genotyping was successful for 72.7% (8/11), with no major mutations to integrase inhibitors found. VR is optimal under first-line TLD after 14 months, even among TLE-exposed, thus confirming the effectiveness of transitioning from TLE to TLD in similar settings, supported by strong pharmacological potency and genetic barrier of dolutegravir.
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Affiliation(s)
- Ezechiel Ngoufack Jagni Semengue
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
- Faculty of Sciences and Technologies, Evangelical University of Cameroon, Bandjoun P.O. Box 0127, Cameroon
| | - Joseph Fokam
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- Faculty of Health Sciences, University of Buea, Buea P.O. Box 063, Cameroon
- National HIV Drug Resistance Working Group, Ministry of Public Health, Yaoundé III P.O. Box 3038, Cameroon
| | - Naomi-Karell Etame
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- School of Health Sciences, Catholic University of Central Africa, Yaoundé P.O. Box 11628, Cameroon
| | - Evariste Molimbou
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- Faculty of Sciences and Technologies, Evangelical University of Cameroon, Bandjoun P.O. Box 0127, Cameroon
| | - Collins Ambe Chenwi
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Désiré Takou
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | | | | | - Bouba Yagai
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Alex Durand Nka
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
- Faculty of Sciences and Technologies, Evangelical University of Cameroon, Bandjoun P.O. Box 0127, Cameroon
| | - Beatrice Dambaya
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Georges Teto
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Aude Christelle Ka’e
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- PhD Courses in Microbiology, Immunology, Infectious Diseases and Transplants (MIMIT), University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Grâce Angong Beloumou
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Sandrine Claire Djupsa Ndjeyep
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Aissatou Abba
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Aurelie Minelle Ngueko Kengni
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- School of Health Sciences, Catholic University of Central Africa, Yaoundé P.O. Box 11628, Cameroon
| | - Michel Carlos Tommo Tchouaket
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- School of Health Sciences, Catholic University of Central Africa, Yaoundé P.O. Box 11628, Cameroon
| | - Nounouce Pamen Bouba
- Directorate for Disease Epidemic and Pandemic Control, Ministry of Public Health, Yaoundé III P.O. Box 3038, Cameroon
| | - Serge-Clotaire Billong
- Central Technical Group, National AIDS Control Committee, Yaoundé II P.O. Box 2005, Cameroon
- Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
| | - Samuel Martin Sosso
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Vittorio Colizzi
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
- Faculty of Sciences and Technologies, Evangelical University of Cameroon, Bandjoun P.O. Box 0127, Cameroon
| | | | - Charles Kouanfack
- School of Health Sciences, Catholic University of Central Africa, Yaoundé P.O. Box 11628, Cameroon
- Faculty of Medicine and Pharmaceutical Sciences, University de Dschang, Dschang P.O. Box 067, Cameroon
| | - Anne-Cecile Zoung-Kanyi Bissek
- Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
- Division of Operational Health Research, Ministry of Public Health, Yaoundé III P.O. Box 3038, Cameroon
| | - Emmanuel Eben-Moussi
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
| | - Maria Mercedes Santoro
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Francesca Ceccherini-Silberstein
- Department of Experimental Medicine, Faculty of Medicine and Surgery, University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
- PhD Courses in Microbiology, Immunology, Infectious Diseases and Transplants (MIMIT), University of Rome “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy
| | - Alexis Ndjolo
- Chantal BIYA International Reference Centre for Research on HIV/AIDS Management and Care, Messa, Yaoundé P.O. Box 3077, Cameroon
- Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé P.O. Box 1364, Cameroon
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13
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Papot E, Jacoby S, Arlinda D, Avihingsanon A, Azwa I, Borok M, Brown D, Cissé M, Dao S, Eriobu N, Kaplan R, Karyana M, Kumarasamy N, Lee J, Losso MH, Matthews GV, Perelis L, Perez-Casas C, Ruxrungtham K, Watkins M, Lane HC, Kelleher A, Law M, Polizzotto MN. Adaption of an ongoing clinical trial to quickly respond to gaps in changing international recommendations: the experience of D 2EFT. HIV Res Clin Pract 2022; 23:37-46. [PMID: 35938597 PMCID: PMC10029359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
A rapidly changing landscape of antiretrovirals and their procurement at scale has permitted the evaluation of new optimised second-line antiretroviral therapy (ART) in low- and middle-income countries. D2EFT is an open-label randomised controlled non-inferiority phase IIIB/IV trial in people living with HIV-1 (PWH) whose first-line non-nucleoside reverse transcriptase inhibitor (NNRTI)-based ART is failing. At inception, it compared a standard of care of boosted darunavir with two nucleos(t)ide reverse transcriptase inhibitors (NRTIs) to the novel NRTI-sparing regimen of boosted darunavir with dolutegravir. Implemented in 2017, participating sites were across Africa, Asia and Latin America. Around the time of implementation, the World Health Organization updated its treatment guidelines and recommended scaling up tenofovir disoproxil fumarate-lamivudine-dolutegravir (TLD). This situation pushed D2EFT investigators to consider the impact of the roll-out of TLD on the D2EFT research question. The protocol team agreed it was important to study TLD in second-line when an NNRTI regimen was failing, and focused on options to expedite the work by studying the question within the existing trial and network. All key issues (statistical, programmatic and financial) were reviewed to assess the benefits and risks of adding a third arm to the ongoing study, as opposed to developing a new randomised clinical trial with the same control arm and within the same network. The development of a new trial was deemed to be longer than adding a third arm, and to create a challenging situation with two competing clinical trials at the same sites which would slow down recruitment and impair both trials. On the other hand, adding a third arm would be demanding in terms of operationalisation, increased sample size and statistical biases to control. The optimal strategy was deemed to be the addition of a third arm, arriving retrospectively at a simplified multi-arm multi-stage clinical trial design to achieve statistical validity. The D2EFT study maintains additional value in a quickly evolving second-line ART strategy allowed by the progress in global access to ART.
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Affiliation(s)
- Emmanuelle Papot
- Therapeutic and Vaccine Research Program, The Kirby Institute, University of New South Wales Sydney, Sydney, NSW, Australia
| | - Simone Jacoby
- Therapeutic and Vaccine Research Program, The Kirby Institute, University of New South Wales Sydney, Sydney, NSW, Australia
| | - Dona Arlinda
- Indonesia Research Partnership on Infectious Disease, Jakarta, Indonesia
| | - Anchalee Avihingsanon
- The HIV Netherlands Australia Thailand Research Collaboration, Thai Red Cross AIDS Research Centre, Bangkok, Thailand
| | - Iskandar Azwa
- Infectious Diseases Unit, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Margaret Borok
- University of Zimbabwe Clinical Research Centre, Harare, Zimbabwe
| | - Dannae Brown
- Global Medical, ViiV Healthcare, Abbotsford, Australia
| | - Mohamed Cissé
- Faculté des Sciences et techniques de la santé de l'Université Gamal Abdel Nasser de Conakry, University hospital of Donka, Conakry, Guinea
| | - Sounkalo Dao
- University Clinical Research Centre, Bamako, Mali
| | | | | | - Muhammad Karyana
- Indonesia Research Partnership on Infectious Disease, Jakarta, Indonesia
| | - Nagalingeswaran Kumarasamy
- Chennai Antiviral Research and Treatment Clinical Research Site, Infectious Diseases Medical Centre, Voluntary Health Services, Chennai, India
| | - Johnnie Lee
- Global Medical Affairs, Global Public Health, Janssen Pharmaceutical companies of Johnson & Johnson, Plainfield, NJ, USA
| | - Marcelo H Losso
- Coordinación en Investigación Clínica Académica en Latinoamérica Fundación IBIS Buenos Aires, Buenos Aires, Argentina
| | - Gail V Matthews
- Therapeutic and Vaccine Research Program, The Kirby Institute, University of New South Wales Sydney, Sydney, NSW, Australia
| | - Leonardo Perelis
- Coordinación en Investigación Clínica Académica en Latinoamérica Fundación IBIS Buenos Aires, Buenos Aires, Argentina
| | | | - Kiat Ruxrungtham
- The HIV Netherlands Australia Thailand Research Collaboration, Thai Red Cross AIDS Research Centre, Bangkok, Thailand
| | - Melynda Watkins
- Product Development and Regulatory Affairs, Clinton Health Access Initiative, Boston, MA, USA
| | - H Clifford Lane
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Anthony Kelleher
- Immunovirology and Pathogenesis Program, The Kirby Institute, University of New South Wales Sydney, Sydney,Australia
| | - Matthew Law
- Biostatistics and Databases Program, The Kirby Institute, University of New South Wales Sydney, Sydney,Australia
| | - Mark N Polizzotto
- Therapeutic and Vaccine Research Program, The Kirby Institute, University of New South Wales Sydney, Sydney, NSW, Australia
- Department of Haematology, The Kinghorn Cancer Centre, St Vincent's Hospital, Darlinghurst, Australia
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14
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Shah N, Esber A, Sean Cavanaugh J, Agaba P, Dear N, Iroezindu M, Bahemana E, Kibuuka H, Owuoth J, Maswai J, Singoei V, Crowell TA, Polyak CS, Ake JA. Transitioning women to first-line preferred TLD regimen is lagging in Sub-Saharan Africa. Clin Infect Dis 2022:ciac555. [PMID: 35788648 DOI: 10.1093/cid/ciac555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 06/23/2022] [Accepted: 06/30/2022] [Indexed: 11/14/2022] Open
Abstract
INTRODUCTION In 2019, the World Health Organization (WHO) recommended tenofovir disoproxil fumarate-lamivudine-dolutegravir (TLD) as the preferred first line regimen for adults and adolescents regardless of childbearing status. Nevertheless, final eligibility is determined by local policies which may vary from WHO recommendations. We examined TLD transition by gender across five PEPFAR-supported HIV care programs in sub-Saharan Africa. METHODS The African Cohort Study (AFRICOS) enrolls people living with HIV (PLWH) engaged in care in Uganda, Kenya (South Rift Valley and Kisumu West), Tanzania and Nigeria. PLWH with at least one study visit after the country introduced TLD were included. We generated Kaplan-Meier (KM) curves to compare TLD transition by gender from 1) time countries' introduction of TLD and 2) time of TLD eligibility according to local policies. RESULTS Among 2.476 participants enrolled through September 2021 at 4 sites in sub-Saharan Africa and eligible to transition to TLD, fewer women (68%) compared to men (80%, p < 0.001) were taking TLD. Kaplan-Meier analysis showed time to transition varied by site, with women in Tanzania transitioning at the same rate as men. In Nigeria, women initially had a slower transition but caught up to men. After adjusting for local policies, women[1] in Kisumu West transitioned at the same rate as men. In South Rift Valley and Uganda, women were less likely to be transitioned. CONCLUSIONS Despite TLD being the WHO's preferred regimen since 2019, transition of women to potentially lifesaving TLD has been slower than men at certain clinical sites even after accounting for local eligibility criteria.
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Affiliation(s)
- Neha Shah
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
| | - Allahna Esber
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, USA
| | - J Sean Cavanaugh
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
| | - Patricia Agaba
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, USA
| | - Nicole Dear
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, USA
| | - Michael Iroezindu
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- HJF Medical Research International, Abuja, Nigeria
| | - Emmanuel Bahemana
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- HJF Medical Research International, Mbeya, Tanzania
| | - Hannah Kibuuka
- Makerere University Walter Reed Project, Kampala, Uganda
| | - John Owuoth
- U.S. Army Medical Research Directorate - Africa, Kisumu, Kenya
- HJF Medical Research International, Kisumu, Kenya
| | - Jonah Maswai
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- HJF Medical Research International, Kericho, Kenya
| | - Valentine Singoei
- U.S. Army Medical Research Directorate - Africa, Kisumu, Kenya
- HJF Medical Research International, Kisumu, Kenya
| | - Trevor A Crowell
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, USA
| | - Christina S Polyak
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, USA
| | - Julie A Ake
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, USA
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15
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De Saint-Hubert M, Verbeek N, Bäumer C, Esser J, Wulff J, Nabha R, Van Hoey O, Dabin J, Stuckmann F, Vasi F, Radonic S, Boissonnat G, Schneider U, Rodriguez M, Timmermann B, Thierry-Chef I, Brualla L. Validation of a Monte Carlo Framework for Out-of-Field Dose Calculations in Proton Therapy. Front Oncol 2022; 12:882489. [PMID: 35756661 PMCID: PMC9213663 DOI: 10.3389/fonc.2022.882489] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/04/2022] [Indexed: 11/30/2022] Open
Abstract
Proton therapy enables to deliver highly conformed dose distributions owing to the characteristic Bragg peak and the finite range of protons. However, during proton therapy, secondary neutrons are created, which can travel long distances and deposit dose in out-of-field volumes. This out-of-field absorbed dose needs to be considered for radiation-induced secondary cancers, which are particularly relevant in the case of pediatric treatments. Unfortunately, no method exists in clinics for the computation of the out-of-field dose distributions in proton therapy. To help overcome this limitation, a computational tool has been developed based on the Monte Carlo code TOPAS. The purpose of this work is to evaluate the accuracy of this tool in comparison to experimental data obtained from an anthropomorphic phantom irradiation. An anthropomorphic phantom of a 5-year-old child (ATOM, CIRS) was irradiated for a brain tumor treatment in an IBA Proteus Plus facility using a pencil beam dedicated nozzle. The treatment consisted of three pencil beam scanning fields employing a lucite range shifter. Proton energies ranged from 100 to 165 MeV. A median dose of 50.4 Gy(RBE) with 1.8 Gy(RBE) per fraction was prescribed to the initial planning target volume (PTV), which was located in the cerebellum. Thermoluminescent detectors (TLDs), namely, Li-7-enriched LiF : Mg, Ti (MTS-7) type, were used to detect gamma radiation, which is produced by nuclear reactions, and secondary as well as recoil protons created out-of-field by secondary neutrons. Li-6-enriched LiF : Mg,Cu,P (MCP-6) was combined with Li-7-enriched MCP-7 to measure thermal neutrons. TLDs were calibrated in Co-60 and reported on absorbed dose in water per target dose (μGy/Gy) as well as thermal neutron dose equivalent per target dose (μSv/Gy). Additionally, bubble detectors for personal neutron dosimetry (BD-PND) were used for measuring neutrons (>50 keV), which were calibrated in a Cf-252 neutron beam to report on neutron dose equivalent dose data. The Monte Carlo code TOPAS (version 3.6) was run using a phase-space file containing 1010 histories reaching an average standard statistical uncertainty of less than 0.2% (coverage factor k = 1) on all voxels scoring more than 50% of the maximum dose. The primary beam was modeled following a Fermi–Eyges description of the spot envelope fitted to measurements. For the Monte Carlo simulation, the chemical composition of the tissues represented in ATOM was employed. The dose was tallied as dose-to-water, and data were normalized to the target dose (physical dose) to report on absorbed doses per target dose (mSv/Gy) or neutron dose equivalent per target dose (μSv/Gy), while also an estimate of the total organ dose was provided for a target dose of 50.4 Gy(RBE). Out-of-field doses showed absorbed doses that were 5 to 6 orders of magnitude lower than the target dose. The discrepancy between TLD data and the corresponding scored values in the Monte Carlo calculations involving proton and gamma contributions was on average 18%. The comparison between the neutron equivalent doses between the Monte Carlo simulation and the measured neutron doses was on average 8%. Organ dose calculations revealed the highest dose for the thyroid, which was 120 mSv, while other organ doses ranged from 18 mSv in the lungs to 0.6 mSv in the testes. The proposed computational method for routine calculation of the out-of-the-field dose in proton therapy produces results that are compatible with the experimental data and allow to calculate out-of-field organ doses during proton therapy.
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Affiliation(s)
- Marijke De Saint-Hubert
- Research in Dosimetric Applications, Belgian Nuclear Research Center (SCK CEN), Mol, Belgium
| | - Nico Verbeek
- West German Proton Therapy Centre Essen WPE, Essen, Germany.,West German Cancer Center (WTZ), Essen, Germany.,Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
| | - Christian Bäumer
- West German Proton Therapy Centre Essen WPE, Essen, Germany.,West German Cancer Center (WTZ), Essen, Germany.,Radiation Oncology and Imaging, German Cancer Consortium DKTK, Heidelberg, Germany.,Department of Physics, TU Dortmund University, Dortmund, Germany
| | - Johannes Esser
- West German Proton Therapy Centre Essen WPE, Essen, Germany.,West German Cancer Center (WTZ), Essen, Germany.,Faculty of Mathematics and Science Institute of Physics and Medical Physics. Heinrich-Heine University, Düsseldorf, Germany
| | - Jörg Wulff
- West German Proton Therapy Centre Essen WPE, Essen, Germany.,West German Cancer Center (WTZ), Essen, Germany
| | - Racell Nabha
- Research in Dosimetric Applications, Belgian Nuclear Research Center (SCK CEN), Mol, Belgium
| | - Olivier Van Hoey
- Research in Dosimetric Applications, Belgian Nuclear Research Center (SCK CEN), Mol, Belgium
| | - Jérémie Dabin
- Research in Dosimetric Applications, Belgian Nuclear Research Center (SCK CEN), Mol, Belgium
| | - Florian Stuckmann
- West German Proton Therapy Centre Essen WPE, Essen, Germany.,Faculty of Mathematics and Science Institute of Physics and Medical Physics. Heinrich-Heine University, Düsseldorf, Germany.,Klinikum Fulda GAG, Universitätsmedizin Marburg, Fulda, Zurich, Germany
| | - Fabiano Vasi
- Physik Institut, Universität Zürich, Zürich, Switzerland
| | | | | | - Uwe Schneider
- Physik Institut, Universität Zürich, Zürich, Switzerland
| | - Miguel Rodriguez
- Hospital Paitilla, Panama City, Panama.,Instituto de Investigaciones Cientificas y de Alta Tecnología INDICASAT-AIP, Panama City, Panama
| | - Beate Timmermann
- West German Proton Therapy Centre Essen WPE, Essen, Germany.,West German Cancer Center (WTZ), Essen, Germany.,Faculty of Medicine, University of Duisburg-Essen, Essen, Germany.,Radiation Oncology and Imaging, German Cancer Consortium DKTK, Heidelberg, Germany.,Department of Particle Therapy, University Hospital Essen, Essen, Germany
| | - Isabelle Thierry-Chef
- Radiation Programme, Barcelona Institute for Global Health (ISGlobal), Barcelona, Spain.,University Pompeu Fabra, Barcelona, Spain.,CIBER Epidemiología y Salud Pública, Madrid, Spain
| | - Lorenzo Brualla
- West German Proton Therapy Centre Essen WPE, Essen, Germany.,West German Cancer Center (WTZ), Essen, Germany.,Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
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16
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Singh T, Muscroft N, Collier N, England A. A comparison of effective dose and risk for different collimation options used in AP shoulder radiography. Radiography (Lond) 2021; 28:394-399. [PMID: 34887196 DOI: 10.1016/j.radi.2021.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/01/2021] [Accepted: 11/19/2021] [Indexed: 11/15/2022]
Abstract
INTRODUCTION Radiography forms the cornerstone of the evaluation of shoulder disorders. While the benefits of radiography exceed the risks, there continues to be a compelling case for reduction of radiation exposure from diagnostic radiography. The aim of this project was to evaluate the radiation dose and risk for a variety of collimation settings used during anteroposterior (AP) shoulder radiography. METHODS This was a phantom based study where an ATOM adult dosimetry phantom was loaded with 272 thermoluminescent dosimeters (TLDs). Following loading, the phantom was setup for an AP shoulder X-ray projection with standard 25 × 30 cm rectangular collimation. The phantom was exposed three times and then the TLDs were removed and read. The experiment was repeated using a diamond shaped collimation and rectangular collimation with a minimum field of view to portray only relevant anatomy. Using the TLD dose measurements the effective doses and radiation risks were determined and compared. RESULTS As expected, organs neighbouring the shoulder experienced the highest absorbed doses (greater than 0.01 mGy); these organs included breast, lung and thyroid gland. The effective doses for standard rectangular, small rectangular and diamond collimation were 0.011, 0.008 and 0.016 mSv, respectively. When compared to standard collimation, a small field of view reduced effective dose by 27.3% and when moving to a diamond shape there was a 45.5% increase. The differences are likely driven by differences in the coverage of the radiosensitive lung and breast tissue. CONCLUSION By utilising a variety of different collimation settings, effective dose can be reduced. Reducing the radiation dose is both financially beneficial and results in a lower stochastic risk for patients. Image quality must also be considered when choosing different collimation settings. It stands to reason that by reducing the field size, dose will be reduced, and our study has served to quantify the effects in a practical situation. IMPLICATIONS FOR PRACTICE The utilisation of smaller/tight collimation is recommended as it offers the lowest dose when compared with other types of collimations. Although well-known this study serves to remind practitioners of the practical importance of collimation and is associated effect on effective dose and risk.
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Affiliation(s)
- T Singh
- School of Allied Health Professions, Keele University, Keele, Staffordshire, UK
| | - N Muscroft
- Warrington & Halton Teaching Hospitals NHS Trust, Warrington, UK
| | - N Collier
- Lancashire Teaching Hospitals NHS Trust, Preston, UK
| | - A England
- School of Allied Health Professions, Keele University, Keele, Staffordshire, UK; Discipline of Medical Imaging, School of Medicine, University College Cork, Ireland.
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Pavičar B, Davidović J, Petrović B, Vuleta G, Trivić S, Šajinović V, Egeljić-Mihailović N, Todorović N, Predojević B. Nuclear medicine staff exposure to ionising radiation in 18F-FDG PET/CT practice: a preliminary retrospective study. Arh Hig Rada Toksikol 2021; 72:216-24. [PMID: 34587667 DOI: 10.2478/aiht-2021-72-3517] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 09/01/2021] [Indexed: 12/15/2022] Open
Abstract
This retrospective study provides an insight into the levels of radiation exposure of six nuclear medicine (NM) staff (four technologists and two nurses) performing routine diagnostic 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET/CT) at the University Clinical Centre of the Republic of Srpska, Department of Nuclear Medicine and Thyroid Disorders, Banja Luka, Bosnia and Herzegovina. Data analysis included monthly staff exposure measured with personal thermoluminescent dosimeters (TLD) between June and December 2018, quantified in terms of normalised dose for the whole body [Hp(10)] and dominant hand [Hp(0.07)] and their comparison between each staff member and between the two groups (technologists and nurses). The study goal was to establish how our Department compared with reports from other PET/CT centres worldwide in terms of annual number of procedures and exposure limits and whether there could be room for further improvements in radiation protection. The number of procedures rose considerably from 208 in 2016 to 876 in 2019 and was 423 in the observed seven-month period. Mean individual whole-body exposure dose per GBq of injected 18F-FDG activity, [Hp(10)/A] was 18.55 μSv/GBq for the four technologists and 15.61 μSv/GBq for the two nurses. Mean dominant-hand exposure dose per GBq of injected 18F-FDG activity [Hp(0.07)/A] was 16.99 μSv/GBq and 25.44 μSv/GBq for the two groups, respectively. The average annual cumulative dose for all staff was (1.06±0.29) mSv for Hp(10) and (1.15±0.32) mSv for Hp(0.07). These results are comparable with those of similar studies. Staff doses were well below the annual limits. Nurses received slightly higher extremity doses than technologists. In view of the increasing trends in the number of PET/CT procedures, dose monitoring should be continued to identify exposure hotspots and maintain doses as low as possible.
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Frank M, Urban T, Willer K, Noichl W, De Marco F, Schick R, Gleich B, Schegerer A, Lechel U, Meyer P, Mohr J, Koehler T, Yaroshenko A, Maack I, Pralow T, Proksa R, Renger B, Noël P, Fingerle A, Pfeiffer D, Rummeny E, Herzen J, Pfeiffer F. Dosimetry on first clinical dark-field chest radiography. Med Phys 2021; 48:6152-6159. [PMID: 34314019 DOI: 10.1002/mp.15132] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 06/02/2021] [Accepted: 06/30/2021] [Indexed: 12/20/2022] Open
Abstract
PURPOSE The purpose of this study was to evaluate the dose characteristic for patient examinations at the first clinical X-ray dark-field chest radiography system and to determine whether the effective patient dose is within a clinically acceptable dose range. METHODS A clinical setup for grating-based dark-field chest radiography was constructed and commissioned, operating at a tube voltage of 70 kVp. Thermoluminescent dosimeter (TLD) measurements were conducted using an anthropomorphic phantom modeling the reference person to obtain a conversion coefficient relating dose area product (DAP) to effective patient dose at the dark-field system. For 92 patients, the DAP values for posterior-anterior measurements were collected at the dark-field system. Using the previously determined conversion coefficient, the effective dose was calculated. RESULTS A reference person, modeled by an anthropomorphic phantom, receives an effective dose of 35 µSv. For the examined patients, a mean effective dose of 39 µSv was found. CONCLUSIONS The effective dose at the clinical dark-field radiography system, generating both attenuation and dark-field images, is within the range of reported standard dose values for chest radiography.
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Affiliation(s)
- Manuela Frank
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Theresa Urban
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Konstantin Willer
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Wolfgang Noichl
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Fabio De Marco
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Rafael Schick
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Bernhard Gleich
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Alexander Schegerer
- Department of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Neuherberg, Germany
| | - Ursula Lechel
- Department of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Neuherberg, Germany
| | - Pascal Meyer
- Karlsruhe Institute of Technology, Institute of Microstructure Technology, Eggenstein-Leopoldshafen, Germany
| | - Juergen Mohr
- Karlsruhe Institute of Technology, Institute of Microstructure Technology, Eggenstein-Leopoldshafen, Germany
| | | | | | - Ingo Maack
- Philips Medical Systems DMC GmbH, Hamburg, Germany
| | | | | | - Bernhard Renger
- Department of Diagnostic and Interventional Radiology, School of Medicine & Klinikum rechts der Isar, Technical University of Munich, München, Germany
| | - Peter Noël
- Department of Diagnostic and Interventional Radiology, School of Medicine & Klinikum rechts der Isar, Technical University of Munich, München, Germany
| | - Alexander Fingerle
- Department of Diagnostic and Interventional Radiology, School of Medicine & Klinikum rechts der Isar, Technical University of Munich, München, Germany
| | - Daniela Pfeiffer
- Department of Diagnostic and Interventional Radiology, School of Medicine & Klinikum rechts der Isar, Technical University of Munich, München, Germany
| | - Ernst Rummeny
- Department of Diagnostic and Interventional Radiology, School of Medicine & Klinikum rechts der Isar, Technical University of Munich, München, Germany
| | - Julia Herzen
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
| | - Franz Pfeiffer
- Chair of Biomedical Physics, Department of Physics, School of Natural Sciences and Munich School of BioEngineering, Technical University of Munich, Garching, Germany.,Department of Diagnostic and Interventional Radiology, School of Medicine & Klinikum rechts der Isar, Technical University of Munich, München, Germany
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Marot M, Elter A, Mann P, Schwahofer A, Lang C, Johnen W, Körber SA, Beuthien-Baumann B, Gillmann C. Technical Note: On the feasibility of performing dosimetry in target and organ at risk using polymer dosimetry gel and thermoluminescence detectors in an anthropomorphic, deformable, and multimodal pelvis phantom. Med Phys 2021; 48:5501-5510. [PMID: 34260079 DOI: 10.1002/mp.15096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 05/28/2021] [Accepted: 06/25/2021] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE To assess the feasibility of performing dose measurements in the target (prostate) and an adjacent organ at risk (rectum) using polymer dosimetry gel and thermoluminescence detectors (TLDs) in an anthropomorphic, deformable, and multimodal pelvis phantom (ADAM PETer). METHODS The 3D printed prostate organ surrogate of the ADAM PETer phantom was filled with polymer dosimetry gel. Nine TLD600 (LiF:Mg,Ti) were installed in 3 × 3 rows on a specifically designed 3D-printed TLD holder. The TLD holder was inserted into the rectum at the level of the prostate and fixed by a partially inflated endorectal balloon. Computed tomography (CT) images were taken and treatment planning was performed. A prescribed dose of 4.5 Gy was delivered to the planning target volume (PTV). The doses measured by the dosimetry gel in the prostate and the TLDs in the rectum ("measured dose") were compared to the doses calculated by the treatment planning system ("planned dose") on a voxel-by-voxel basis. RESULTS In the prostate organ surrogate, the 3D-γ-index was 97.7% for the 3% dose difference and 3 mm distance to agreement criterium. In the center of the prostate organ surrogate, measured and planned doses showed only minor deviations (<0.1 Gy, corresponding to a percentage error of 2.22%). On the edges of the prostate, slight differences between planned and measured doses were detected with a maximum deviation of 0.24 Gy, corresponding to 5.3% of the prescribed dose. The difference between planned and measured doses in the TLDs was on average 0.08 Gy (range: 0.02-0.21 Gy), corresponding to 1.78% of the prescribed dose (range: 0.44%-4.67%). CONCLUSIONS The present study demonstrates the feasibility of using polymer dosimetry gel and TLDs for 3D and 1D dose measurements in the prostate and the rectum organ surrogates in an anthropomorphic, deformable and multimodal phantom. The described methodology might offer new perspectives for end-to-end tests in image-guided adaptive radiotherapy workflows.
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Affiliation(s)
- Mathieu Marot
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Medicine, University of Heidelberg, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Alina Elter
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany
| | - Philipp Mann
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,HQ-Imaging GmbH, Heidelberg, Germany
| | - Andrea Schwahofer
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Clemens Lang
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Wibke Johnen
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Stefan A Körber
- Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Bettina Beuthien-Baumann
- Department of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Heidelberg, Germany
| | - Clarissa Gillmann
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Heidelberg, Germany
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20
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Puchalska M. Modelling and measurements of distributions in an adult human phantom undergoing proton scanning beam radiotherapy: lung- and prostate-located tumours. Radiat Environ Biophys 2021; 60:243-256. [PMID: 33651168 PMCID: PMC8116245 DOI: 10.1007/s00411-021-00895-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 02/01/2021] [Indexed: 06/12/2023]
Abstract
Proton radiotherapy has been shown to offer a significant dosimetric advantage in cancer patients, in comparison to conventional radiotherapy, with a decrease in dose to healthy tissue and organs at risk, because the bulk of the beam energy is deposited in the Bragg peak to be located within a tumour. However, it should be kept in mind that radiotherapy of cancer is still accompanied by adverse side effects, and a better understanding and improvement of radiotherapy can extend the life expectancy of patients following the treatment of malignant tumours. In this study, the dose distributions measured with thermoluminescent detectors (TLDs) inside a tissue-equivalent adult human phantom exposed for lung and prostate cancer using the modern proton beam scanning radiotherapy technique were compared. Since the TLD detection efficiency depends on the ionization density of the radiation to be detected, and since this efficiency is detector specific, four different types of TLDs were used to compare their response in the mixed radiation fields. Additionally, the dose distributions from two different cancer treatment modalities were compared using the selected detectors. The measured dose values were benchmarked against Monte Carlo simulations and available literature data. The results indicate an increase in the lateral dose with an increase of the primary proton energy. However, the radiation quality factor of the mixed radiation increases by 20% in the vicinity to the target for the lower initial proton energy, due to the production of secondary charged particles of low-energy and short range. For the cases presented here the MTS-N TLD detector seems to be the most optimal tool for dose measurements within the target volume, while the MCP-N TLD detector, due to an interplay of its enhanced thermal neutron response and decreased detection efficiency to highly ionising radiation, is a better choice for the out-of-field measurements. The pairs of MTS-6 and MTS-7 TLDs used also in this study allowed for a direct measurement of the neutron dose equivalent. Before it can be concluded that they offer an alternative to the time-consuming nuclear track detectors, however, more research is needed to unambiguously confirm whether this observation was just accidental or whether it only applies to certain cases. Since there is no universal detector, which would allow the determination of the dosimetric quantities relevant for risk estimation, this work expands the knowledge necessary to improve the quality of dosimetry data and might help scientists and clinicians in choosing the right tools to measure radiation doses in mixed radiation fields.
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Affiliation(s)
- Monika Puchalska
- Radiation Physics, Technische Universität Wien, Stadionalle 2, 1020, Vienna, Austria.
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El-Faramawy N, Chopra V, Rawash S, El-Hafez AA, Dhoble SJ. Response of TLD-600/TLD-700 and CR-39 to neutrons for medical dosimetry. LUMINESCENCE 2021; 36:1257-1264. [PMID: 33835719 DOI: 10.1002/bio.4051] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 02/21/2021] [Accepted: 04/06/2021] [Indexed: 11/06/2022]
Abstract
In this study, thermoluminescence detectors (TLD)-600 and TLD-700 were used under different conditions to study neutron dosimetry for its application in medical dosimetry as albedo dosimeters. 6 LiF has a high cross-section for neutrons and is more sensitive to neutrons than to gamma radiation. Conversely, TLD-700 showed a better response to gamma radiation. Therefore, to obtain the response for neutrons, the responses for TLD-600 and TLD-700 were subtracted. A cadmium sheet was used to absorb incident thermal neutrons so that detector measured only backscattered neutrons from the albedo dosimeter. A Perspex sheet was used as a moderator to thermalize the fast neutron source Am-Be used in the experiment. CR-39 was used to detect fast neutrons and act as an albedo dosimeter when covered with a 10 B disc. Both TLD and CR-39 dosimeters were successful in detecting scattered neutrons in radiotherapy rooms.
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Affiliation(s)
- Nabil El-Faramawy
- Department of Physics, Faculty of Science, Ain shams University, Abbassia, Cairo, Egypt
| | - Vibha Chopra
- P.G. Department of Physics & Electronics, DAV College, Amritsar, Punjab, India
| | - Shrouk Rawash
- Department of Physics, Faculty of Science, Ain shams University, Abbassia, Cairo, Egypt
| | - Arafa Abd El-Hafez
- Ionizing Radiation Metrology Laboratory (IRML), National Institute for Standards (NIS), Egypt
| | - Sanjay J Dhoble
- Department of Physics, R.T.M. Nagpur University, Nagpur, India
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Yin WW, Zheng XW, Wang ZQ, Chen WJ, Tyan YS, Chen TR. Ambient and personnel occupational dose assessment in a Hospital's PET/CT center. Appl Radiat Isot 2020; 169:109466. [PMID: 33340787 DOI: 10.1016/j.apradiso.2020.109466] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 09/03/2020] [Accepted: 10/08/2020] [Indexed: 11/24/2022]
Abstract
This study used thermoluminescent dosimeters (TLDs) to measure cumulative radiation doses in a PET/CT center. It covered 18 areas and four personnel groups. Because the isolated lead shielding separated the patients from the nurses, wearing protective clothing when injecting radiopharmaceuticals was unnecessary. Fingertip doses of the dispensing and nurse groups were below the occupational limit. Current radiopharmaceutical transportation and injection operations in this PET/CT center provide considerable radiation protection to medical personnel.
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Affiliation(s)
- Wei-Wei Yin
- Department of Radiology, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiang-Wu Zheng
- Department of Radiology, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhi-Qiang Wang
- Department of Radiology, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Wei-Jian Chen
- Department of Radiology, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yeu-Sheng Tyan
- School of Medicine, Chung Shan Medical University, Taichung, Taiwan; Department of Medical Image, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Tou-Rong Chen
- Department of Medical Image, Chung Shan Medical University Hospital, Taichung, Taiwan; Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan.
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Bassi S, Berrigan L, Zuchora A, Fahy L, Moore M. End-to-end dosimetric audit: A novel procedure developed for Irish HDR brachytherapy centres. Phys Med 2020; 80:221-9. [PMID: 33190078 DOI: 10.1016/j.ejmp.2020.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 09/28/2020] [Accepted: 10/05/2020] [Indexed: 11/24/2022] Open
Abstract
PURPOSE A dosimetric audit of Ir-192 high dose rate (HDR) brachytherapy remote after-loading units was carried out in 2019. All six brachytherapy departments on the island of Ireland participated in an end-to-end test and in a review of local HDR dosimetry procedures. MATERIALS AND METHODS A 3D-printed customised phantom was created to position the following detectors at known distances from the HDR source: a Farmer ionization chamber, GafChromic film and thermoluminescent dosimeters (TLDs). Dedicated HDR applicator needles were used to position an Ir-192 source at 2 cm distance from these detectors. The end-to-end dosimetry audit pathway was performed at each host site and included the stages of imaging, applicator reconstruction, treatment planning and delivery. Deviations between planned and measured dose distributions were quantified using gamma analysis methods. Local procedures were also discussed between auditors and hosts. RESULTS The mean difference between Reference Air Kerma Rate (RAKR) measured during the audit and RAKR specified by the vendor source certificate was 1.3%. The results of end-to-end tests showed a mean difference between calculated and measured dose of 2.5% with TLDs and less than 0.5% with Farmer chamber measurements. GafChromic films showed a mean gamma passing rates of >95% for plastic and metal applicators with 2%/1 mm global tolerance criteria. CONCLUSIONS The results of this audit indicate dosimetric consistency between centres. The 'end to end' dosimetry audit methodology for HDR brachytherapy has been successfully implemented in a multicentre environment, which included different models of Ir-192 sources and different treatment planning systems. The ability to create a 3D-printed water-equivalent phantom customised to accurately position all three detector types simultaneously at controlled distances from the Ir-192 source under evaluation gives good reproducibility for end-to-end methodology.
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Chalupnik S, Skubacz K. A method for the simultaneous measurement of radon and thoron PAEC concentrations in air using a TLD monitor. J Radiol Prot 2020; 40:1236-1246. [PMID: 33124603 DOI: 10.1088/1361-6498/abb121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
The idea of using a device with thermo-luminescent detectors (TLD) for the simultaneous measurement of radon (Rn-222) and thoron (Rn-220) decay products' concentrations was invented and developed in the Silesian Centre for Environmental Radioactivity at the Central Mining Institute, Katowice, Poland. The results of a preliminary analysis of the technical applicability, the required minimum period of air sampling and the optimised time schedule proved that such measurements can provide information about the potential alpha energy concentrations (PAECs) of radon and thoron decay products (TnDP).Following the analysis, preliminary measurements were performed at several locations-in a thoron chamber, in dwellings and even outdoors. Surprisingly, the maximum PAEC of the TnDP in the basement of a twin house in the Upper Silesia region was as high as 0.68 ± 0.15µJ m-3. This paper presents the results of those measurements.
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Affiliation(s)
- Stanislaw Chalupnik
- Silesian Centre for Environmental Radioactivity Central Mining Institute, Katowice, Poland
| | - Krystian Skubacz
- Silesian Centre for Environmental Radioactivity Central Mining Institute, Katowice, Poland
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Bulski W, Chełmiński K, Ulkowski P, Ślusarczyk-Kacprzyk W, Grabska I, Kukołowicz P. The role of SSDL in quality assurance in radiotherapy. Rep Pract Oncol Radiother 2020; 25:902-905. [PMID: 32982598 DOI: 10.1016/j.rpor.2020.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/15/2020] [Accepted: 08/11/2020] [Indexed: 10/23/2022] Open
Abstract
This paper describes the role of the Polish Secondary Standard Dosimetry Laboratory (SSDL) in quality assurance in radiotherapy by means of providing calibration of ionisation chambers, TLD postal dosimetry audits and end-to-end audits for radiation therapy. A historical review of the methods and results are presented. The influence of the SSDL in Warsaw on radiation protection of patients in Poland is discussed. The International Atomic Energy Agency together with World Health Organisation (IAEA/WHO), through its network of SSDLs around the world, propagates newly developed methods for calibration and auditing. Suitable high quality equipment was provided by the IAEA, as well as special materials and technical support to the SSDL in Warsaw. The activity of the SSDL and the services provided for Polish radiotherapy centres have resulted in a reduction of discrepancies between planned doses and doses delivered to patients. The newly tested IAEA methods of end-to-end on-site dosimetry audits allow for monitoring and improving the quality of IMRT in Poland. The traceability of standards used for the calibration of therapy level dosimeters from Polish radiotherapy centres is assured by the IAEA dosimetry laboratory. The consistency of methods performed in the Polish SSDL with the ISO:17025 norm is supervised by the Polish Centre for Accreditation - a member of International Laboratory Accreditation Cooperation (ILAC), for calibration and testing. Due to the rapid technological development of radiotherapy, special attention has to be paid to newly developed methods for dosimetry auditing and institutions which provide services for assuring radiation safety of patients.
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Affiliation(s)
- Wojciech Bulski
- Secondary Standard Dosimetry Laboratory, Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Roentgen Str. 5, 02-781 Warsaw, Poland
| | - Krzysztof Chełmiński
- Secondary Standard Dosimetry Laboratory, Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Roentgen Str. 5, 02-781 Warsaw, Poland
| | - Piotr Ulkowski
- Secondary Standard Dosimetry Laboratory, Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Roentgen Str. 5, 02-781 Warsaw, Poland
| | - Wioletta Ślusarczyk-Kacprzyk
- Secondary Standard Dosimetry Laboratory, Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Roentgen Str. 5, 02-781 Warsaw, Poland
| | - Iwona Grabska
- Secondary Standard Dosimetry Laboratory, Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Roentgen Str. 5, 02-781 Warsaw, Poland
| | - Paweł Kukołowicz
- Secondary Standard Dosimetry Laboratory, Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Roentgen Str. 5, 02-781 Warsaw, Poland
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Liuzzi R, Piccolo C, D'Avino V, Clemente S, Oliviero C, Cella L, Pugliese M. Dose-Response of TLD-100 in the Dose Range Useful for Hypofractionated Radiotherapy. Dose Response 2020; 18:1559325819894081. [PMID: 32110167 PMCID: PMC7019407 DOI: 10.1177/1559325819894081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 02/06/2023] Open
Abstract
Purpose: The aim of the study was to exploit the feasibility of thermoluminescent
dosimeters (TLDs) in radiation therapy techniques in which high dose per
fraction is involved. Methods: Dose–response of TLD-100 (LiF: Mg, Ti) was investigated in both 6-MV photon
and 6-MeV electron beams. The element correction factor (ECF) generation
method was applied to check the variability of the TLDs response. Two
batches of 50 TLDs were divided into groups and exposed in the dose range 0
to 30 Gy. Regression analysis was performed with both linear and quadratic
models. For each irradiation beam, the calibration curves were obtained in 3
dose range 0 to 8 Gy, 0 to 10 Gy, and 0 to 30 Gy. The best-fitting model was
assessed by the Akaike Information Criterion test. Results: The ECF process resulted a useful tool to reduce the coefficients of
variation from original values higher than 5% to about 3.5%, for all the
batches exposed. The results confirm the linearity of dose–response curve
below the dose level of 10 Gy for photon and electron beam and the
supralinear trend above. Conclusion: The TLDs are suitable dosimeters for dose monitoring and verification in
radiation treatment involving dose up to 30 Gy in a single fraction.
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Affiliation(s)
- Raffaele Liuzzi
- Institute of Biostructure and Bioimaging, National Research Council (CNR), Naples, Italy
| | | | - Vittoria D'Avino
- Institute of Biostructure and Bioimaging, National Research Council (CNR), Naples, Italy.,National Institute for Nuclear Physics (INFN), Naples, Italy
| | | | | | - Laura Cella
- Institute of Biostructure and Bioimaging, National Research Council (CNR), Naples, Italy
| | - Mariagabriella Pugliese
- National Institute for Nuclear Physics (INFN), Naples, Italy.,Department of Physics "E. Pancini", Federico II University, Naples, Italy
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Shang D, Gu W, Landers A, Woods K, Yu V, Neph R, Tenn S, Sheng K. Technical Note: Robust individual thermoluminescence dosimeter tracking using optical fingerprinting. Med Phys 2020; 47:267-271. [PMID: 31677160 PMCID: PMC9829522 DOI: 10.1002/mp.13895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 01/12/2023] Open
Abstract
PURPOSE The thermoluminescence dosimeter (TLD) has desirable features including low cost, reusability, small size, and relatively low energy dependence. However, the commonly available poly-crystal TLDs (e.g., TLD-100) exhibit high interdetector variability that requires individual calibration for high detection accuracy. To improve individual TLD tracking robustness, we developed an optical fingerprinting method to identify the TLD-100 chips. METHODS Seven hundred and fifty-two images were initially captured using a digital microscope camera to build a feature library for both facets of 376 TLD-100 chips. A median intensity thresholding method was used to segment images into foreground and background. The affine transformation was used to register the segmented images to the same position. The fingerprint of each image was calculated from its registered image. All fingerprints were then recorded in an Elasticsearch® search database. The TLD fingerprint match was tested three times when the library was established and repeated once 20 months later. All chips were irradiated at 0, 1, 4, and 8 Gy on a calibrated clinical MV linac to establish the individual calibration curve. RESULTS The true positive rate of identifying TLDs based on their optical fingerprints was 100% at initialization of the inventory. After 20 months and multiple deployments for characterization, calibration, and dose measurement, the true positive match rate dropped to 99% with zero false-positive matches. The TLDs exhibited high self-consistency in the dose-response test with R2 between 0.988 and 1 with linear regression. CONCLUSIONS The TLD-100 chips surface textures are unique and sufficient to support accurate identification based on the optical fingerprinting. This method provides inexpensive and robust management of the TLDs for individual calibration and dosimetry.
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Affiliation(s)
- Daili Shang
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Wenbo Gu
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Angelia Landers
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Kaley Woods
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Victoria Yu
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Ryan Neph
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Stephen Tenn
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Ke Sheng
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
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Alrehily F, Hogg P, Twiste M, Johansen S, Tootell A. Scoliosis imaging: An analysis of radiation risk in the CT scan projection radiograph and a comparison with projection radiography and EOS. Radiography (Lond) 2019; 25:e68-74. [PMID: 31301794 DOI: 10.1016/j.radi.2019.02.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/21/2019] [Accepted: 02/04/2019] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Scoliosis is defined as a deformity of the spine with lateral curvature in the coronal plane. It requires regular X-ray imaging to monitor the progress of the disorder, therefore scoliotic patients are frequently exposed to radiation. It is important to lower the risk from these exposures for young patients. The aim of this work is to compare organ dose (OD) values resulting from Scan Projection Radiograph (SPR) mode in CT against projection radiography and EOS® imaging system when assessing scoliosis. METHODS A dosimetry phantom was used to represent a 10-year old child. Thermoluminescent dosimetry detectors were used for measuring OD. The phantom was imaged with CT in SPR mode using 27 imaging parameters; projection radiography and EOS machines using local scoliosis imaging procedures. Imaging was performed in anteroposterior, posteroanterior and lateral positions. RESULTS 17 protocols delivered significantly lower radiation dose than projection radiography (p < 0.05). OD values from the CT SPR imaging protocols and projection radiography were statistically significant higher than the results from EOS. No statistically significant differences in OD were observed between 10 imaging protocols and those from projection radiography and EOS imaging protocols (p > 0.05). CONCLUSION EOS has the lowest dose. Where this technology is not available we suggest there is a potential for OD reduction in scoliosis imaging using CT SPR compared to projection radiography. Further work is required to investigate image quality in relation to the measurement of Cobb angle with CT SPR.
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Abstract
Background: The purpose of this study was to estimate the secondary cancer risk of thyroid in standard radiotherapy methods which are commonly used for breast cancer patients. Methods: A total of 64 breast cancer patients (their age range was around 50 years old) who referred to Seyed-Al-Shohada hospital (Isfahan, Iran) were included in this study. The radiotherapy of the mentioned patients was performed using 6-MV photon beams. Dose measurements were also done using thermoluminescent dosimeters. Calculation of the risk of developing secondary cancer in thyroid was done using the Biological Effects of Ionizing Radiation Committee VII and recommended quantity of the International Radiation Protection Commission, excess relative risk. Results: The mean radiation dose to thyroid for the tangential beams, tangential field with supraclavicular (SC) field, and also a tangential field with SC field in modified radical mastectomy (MRM) were 0.883 ± 0.472, 1.512 ± 0.365, and 1.587 ± 0.37, respectively. The risk of developing secondary thyroid cancer over a period of 5 years after breast cancer therapy in the tangential, tangential with a SC field, and also tangential beam with SC field in MRM were 9.974 ± 4.318, 17.891 ± 0.365, and 18.783 ± 4.384, respectively. The mean of the measured thyroid doses in patients treated with tangent fields was significantly lower than the patients under the irradiation of the tangent fields with SC field (P < 0.001). Conclusions: Using radiation protection equipment is suggested for breast cancer patients who treated with the studied radiotherapy methods.
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Affiliation(s)
- Zeinab Momeni
- Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Bagher Tavakoli
- Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Maryam Atarod
- Department of Medical Physics, School of Medicine, Shahrekord University of Medical Sciences, Shahrekord, Iran
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Wu KY, Chen WT, Kuo HN, Pan LF, Pan LK. Estimation and clinical verification of the effective and skin doses for pediatric and adult patients undergoing the cardiac interventional examination using five PMMA phantoms and TLD/ionization chamber technique. Technol Health Care 2019; 27:95-108. [PMID: 31045530 PMCID: PMC6597971 DOI: 10.3233/thc-199010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Effective and skin doses gain much attention since the cardiac catheterization laboratory (CCL) is a place where both patients and medical staff are exposed to X-ray or fluoroscopy environment and gain a cumulative dose during the cardiac interventional procedure. OBJECTIVE These doses for pediatric and adult patients undergone cardiac interventional examination using five PMMA phantoms and thermoluminescence dosimeter (TLD)/ionization chamber technique were estimated in this work with the further clinical verification. METHODS Five PMMA phantoms (10, 30, 50, 70, and 90 kg) were customized to represent baby, child, adult female, adult male, and overweight adult (by Asian complexion standards), respectively, in accordance with the ICRU-48 report. Each phantom could be disassembled into 31 plates to insert TLD chips for measuring X-ray exposed dose or assisted with an auxiliary plate to insert high-sensitivity ionization chamber for surveying low-energy fluoroscopy dose. RESULTS The data acquired from five phantoms were integrated into four semi-empirical formulas, in order to fit the binary quadratic form "Dose = A⋅BMI2+B⋅DAP2+C⋅BMI+ D⋅DAP+E". The latter linked the X-ray and fluoroscopy effective/skin doses, respectively, with a high coefficient of determination R2(from 0.888 to 0.986). CONCLUSIONS The model refinement with DAP share adjustment is envisaged.
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Affiliation(s)
- Keng-Yi Wu
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung, Taiwan
- Department of Cardiology, Taichung Armed Forces General Hospital, Taichung, Taiwan
- Division of Cardiology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Wei-Ting Chen
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung, Taiwan
- Department of Psychiatry, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan
| | - Hsun-Nan Kuo
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung, Taiwan
- Division of Cardiology, Yuan Rung Hospital, Yuanlin, Changhua, Taiwan
| | - Lung-Fa Pan
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung, Taiwan
- Department of Cardiology, Taichung Armed Forces General Hospital, Taichung, Taiwan
| | - Lung-Kwang Pan
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung, Taiwan
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Møller AP, Mousseau TA. Reduced colonization by soil invertebrates to irradiated decomposing wood in Chernobyl. Sci Total Environ 2018; 645:773-779. [PMID: 30031335 DOI: 10.1016/j.scitotenv.2018.07.195] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 07/13/2018] [Accepted: 07/15/2018] [Indexed: 06/08/2023]
Abstract
Soil is inhabited by a range of microbes, invertebrates and vertebrates that disintegrate and decompose dead wood and leaf litter. These communities can be perturbed by ionizing radiation from natural radiation sources or from radiation originating from nuclear accidents such as those at Chernobyl, Fukushima and Three Mile Island. We used experimental manipulations of wood quality due to differences in exposure to ionizing radiation among tree trunks and ambient radiation levels of the soil to test the hypothesis that radioactively contaminated wood would result in a negative correlation between the abundance of soil invertebrates colonizing slices of wood and level of radioactive contamination. We extracted soil invertebrates underneath decomposing wood using mustard powder diluted in water. The abundance of soil invertebrates extracted was highly repeatable at study sites and decreased with increasing ambient radiation and total dose measured with thermoluminescent dosimeters (TLDs). Four 10 cm thick slices of ca. 70-year old Scots pines (Pinus sylvestris) were deposited at 20 sites and the invertebrate taxa and their colonization and their abundance was assessed annually during 2014-2017. There were more soil invertebrates under uncontaminated than contaminated slices of wood. In addition, there were more soil invertebrates in areas with less ambient radioactivity, and there was an interaction effect between contamination of wood and ambient radiation implying that the role of contamination differed among slices. Finally, there was an increase in the abundance of soil invertebrates under wood slices during 2013-2017 implying that the abundance of soil invertebrates increased over time. These findings imply that the abundance of soil animals colonizing wood slices was dependent on background radiation, radioactive contamination of wood and the interaction between contamination of wood and ambient radiation.
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Affiliation(s)
- A P Møller
- Ecologie Systématique Evolution, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, F-91405 Orsay Cedex, France.
| | - T A Mousseau
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
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Aslian H, Delana A, Kaiser SR, Moretti E, Foti C, Bregant P, de Denaro M, Longo F, Severgnini M. A multicenter dosimetry study to evaluate the imaging dose from Elekta XVI and Varian OBI kV-CBCT systems to cardiovascular implantable electronic devices (CIEDs). Phys Med 2018; 55:40-46. [PMID: 30471818 DOI: 10.1016/j.ejmp.2018.10.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 10/02/2018] [Accepted: 10/15/2018] [Indexed: 11/19/2022] Open
Abstract
The increasing use of daily CBCT in radiotherapy has raised concerns about the additional dose delivered to the patient, and it can also become a concern issue for those patients with cardiovascular implantable electronic devices (CIEDs) (Pacemaker [PM] and Implantable Cardioverter Defibrillator [ICD]). Although guidelines highly recommend that the cumulative dose received by CIEDs should be kept as low as possible, and a safe threshold based on patient risk classification needs to be respected, this additional imaging dose is not usually considered. Four centers with different dosimetry systems and different CBCT imaging protocols participated in this multicenter study to investigate the imaging dose to the CIEDs from Elekta XVI and Varian OBI kV-CBCT systems. It was found that although imaging doses received by CIEDs outside the CBCT field are negligible, special attention should be paid to this value when CIEDs are inside the field because the daily use of CBCT can sometimes contribute considerably to the total dose received by a CIED.
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Affiliation(s)
- Hossein Aslian
- Department of Physics, University of Trieste, Trieste, Italy.
| | - Anna Delana
- Department of Medical Physics, S. Chiara Hospital, APSS Trento, Italy.
| | - Stefano Ren Kaiser
- Department of Medical Physics, Fondazione Poliambulanza, Istituto Ospedaliero, Brescia, Italy.
| | - Eugenia Moretti
- Department of Medical Physics, Azienda Sanitaria Universitaria Integrata di Udine, Italy.
| | - Claudio Foti
- Department of Medical Physics, Azienda Sanitaria Universitaria Integrata di Udine, Italy.
| | - Paola Bregant
- Department of Medical Physics, Azienda Sanitaria Universitaria Integrata di Trieste, Trieste, Italy.
| | - Mario de Denaro
- Department of Medical Physics, Azienda Sanitaria Universitaria Integrata di Trieste, Trieste, Italy.
| | - Francesco Longo
- Department of Physics, University of Trieste, Trieste, Italy; National Institute for Nuclear Physics (INFN), Sezione di Trieste, Trieste, Italy.
| | - Mara Severgnini
- Department of Medical Physics, Azienda Sanitaria Universitaria Integrata di Trieste, Trieste, Italy.
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Acun-Bucht H, Tuncay E, Darendeliler E, Kemikler G. Absolute dose verification of static intensity modulated radiation therapy (IMRT) with ion chambers of various volumes and TLD detectors. Rep Pract Oncol Radiother 2018; 23:242-50. [PMID: 29991928 DOI: 10.1016/j.rpor.2018.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 01/12/2018] [Accepted: 04/08/2018] [Indexed: 11/22/2022] Open
Abstract
Aim This study aims at examining absolute dose verification of step-and-shoot intensity modulated radiation treatment (IMRT) of prostate and brain patients by use of ion chambers of two different volumes and thermoluminescent detectors (TLD). Background The volume of the ion chamber (IC) is very important for absolute dose verification of IMRT plans since the IC has a volume average effect. With TLD detectors absolute dose verification can be done measuring the dose of multiple points simultaneously. Materials and methods Ion chambers FC65-P of volume 0.65 cc and semiflex of volume 0.125 cc as well as TLDs were used to measure the central axis absolute dose of IMRT quality assurance (QA) plans. The results were compared with doses calculated by a treatment planning system (TPS). The absolute doses of off axis points located 2 cm and 4 cm away from the isocenter were measured with TLDs. Results The measurements of the 0.125 cc ion chamber were found to be closer to TPS calculations compared to the 0.65 cc ion chamber, for both patient groups. For both groups the root mean square (RMS) differences between doses of the TPS and the TLD detectors are within 3.0% for the central axis and points 2 cm away from the isocenter of each axis. Larger deviations were found at the field edges, which have steep dose gradient. Conclusions The 0.125 cc ion chamber measures the absolute dose of the isocenter more accurately compared to the 0.65 cc chamber. TLDs have good accuracy (within 3.0%) for absolute dose measurements of in-field points.
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Lonski P, Kron T, Taylor M, Phipps A, Franich R, Chua B. Assessment of leakage dose in vivo in patients undergoing radiotherapy for breast cancer. Phys Imaging Radiat Oncol 2018; 5:97-101. [PMID: 33458377 PMCID: PMC7807604 DOI: 10.1016/j.phro.2018.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 03/08/2018] [Accepted: 03/08/2018] [Indexed: 01/02/2023]
Abstract
Background and purpose Accurate quantification of the relatively small radiation doses delivered to untargeted regions during breast irradiation in patients with breast cancer is of increasing clinical interest for the purpose of estimating long-term radiation-related risks. Out-of-field dose calculations from commercial planning systems however may be inaccurate which can impact estimates for long-term risks associated with treatment. This work compares calculated and measured dose out-of-field and explores the application of a correction for leakage radiation. Materials and methods Dose calculations of a Boltzmann transport equation solver, pencil beam-type, and superposition-type algorithms from a commercial treatment planning system (TPS) were compared with in vivo thermoluminescent dosimetry (TLD) measurements conducted out-of-field on the contralateral chest at points corresponding to the thyroid, axilla and contralateral breast of eleven patients undergoing tangential beam radiotherapy for breast cancer. Results Overall, the TPS was found to under-estimate doses at points distal to the radiation field edge with a modern linear Boltzmann transport equation solver providing the best estimates. Application of an additive correction for leakage (0.04% of central axis dose) improved correlation between the measured and calculated doses at points greater than 15 cm from the field edge. Conclusions Application of a correction for leakage doses within peripheral regions is feasible and could improve accuracy of TPS in estimating out-of-field doses in breast radiotherapy.
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Affiliation(s)
- Peta Lonski
- Department of Physical Sciences, Peter MacCallum Cancer Centre Melbourne, Australia.,School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Australia
| | - Tomas Kron
- Department of Physical Sciences, Peter MacCallum Cancer Centre Melbourne, Australia.,School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Australia
| | - Michael Taylor
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Australia
| | - Alicia Phipps
- Radiation Therapy Services, Peter MacCallum Cancer Centre, Australia
| | - Rick Franich
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Australia
| | - Boon Chua
- Nelune Comprehensive Cancer Centre, Prince of Wales Hospital, Randwick, NSW, Australia.,Faculty of Medicine, The University of New South Wales, UNSW Sydney, NSW, Australia
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Aramrun P, Beresford NA, Wood MD. Selecting passive dosimetry technologies for measuring the external dose of terrestrial wildlife. J Environ Radioact 2018; 182:128-137. [PMID: 29227874 DOI: 10.1016/j.jenvrad.2017.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 11/29/2017] [Accepted: 12/04/2017] [Indexed: 06/07/2023]
Abstract
Dosimeters attached to wild animals can be used to validate regulatory assessment approaches and models for estimating radiation exposure of wild animals. Such measurements are also necessary to ensure that robust dose-effect relationships can be developed from the results of field research programmes. This paper presents the first comprehensive evaluation of the different dosimetry technologies available for specifically measuring the external exposure of wildlife. Guidance is provided on the selection of appropriate passive dosimetry approaches for directly measuring external exposure of terrestrial wildlife under field conditions. The characteristics and performance of four available dosimetry technologies (thermoluminescent dosimeter (TLD), optically stimulated luminescent dosimeter (OSLD), radiophotoluminescent dosimeter (RPLD) and direct ion storage, (DIS)) are reviewed. Dosimeter properties, detection limit and dose range, study organisms and the intended application are variables that need to be considered when selecting a suitable dosimetry technology. Evaluated against these criteria, it is suggested that LiF based and Al2O3:C TLDs, OSLD and RPLD could all be used to estimate doses to wildlife. However, only LiF based TLDs have been used to directly measure wildlife doses in field studies to date. DIS is only suitable for comparatively large species (e.g. medium to large mammals), but has the advantage that temporal variation in dose can be recorded. In all cases, dosimeter calibration is required to ensure that the dose measurements reported can be interpreted appropriately for the organisms of interest.
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Affiliation(s)
- Phakphum Aramrun
- School of Environment and Life Science, University of Salford, Manchester, M4 4WT, UK.
| | - Nicholas A Beresford
- School of Environment and Life Science, University of Salford, Manchester, M4 4WT, UK; NERC Centre for Ecology & Hydrology, Lancaster Environment Centre Library Av., Bailrigg, Lancaster, LA14AP, UK
| | - Michael D Wood
- School of Environment and Life Science, University of Salford, Manchester, M4 4WT, UK
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Hosseini Pooya SM, Dashtipour MR, Paydar R, Mianji F, Pourshahab B. A comprehensive dose assessment of irradiated hand by iridium-192 source in industrial radiography. Australas Phys Eng Sci Med 2017; 40:611-6. [PMID: 28871483 DOI: 10.1007/s13246-017-0568-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 06/22/2017] [Indexed: 10/18/2022]
Abstract
Among the various incidents in industrial radiography, inadvertent handling of sources by hands is one of the most frequent incidents in which some parts of the hands may be locally exposed to high doses. An accurate assessment of extremity dose assists medical doctors in selecting appropriate treatments, preventing the injury expansion in the region. In this study, a phantom was designed to simulate a fisted hand of a radiographer when the worker holds a radioactive source in their hands. The local doses were measured using implanted TLDs in the phantom at different distances from a source. Furthermore, skin dose distribution was measured by Gaf-chromic films in the palm region of the phantom. The reliability of the measurements has been studied via analytical as well as Monte-Carlo simulation methods. The results showed that the new phantom design can be used reliably in extremity dose assessments, particularly at the points next to the source.
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Hauri P, Schneider U. Whole-body dose and energy measurements in radiotherapy by a combination of LiF:Mg,Cu,P and LiF:Mg,Ti. Z Med Phys 2017; 28:96-109. [PMID: 28807441 DOI: 10.1016/j.zemedi.2017.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 06/07/2017] [Accepted: 07/09/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE Long-term survivors of cancer who were treated with radiotherapy are at risk of a radiation-induced tumor. Hence, it is important to model the out-of-field dose resulting from a cancer treatment. These models have to be verified with measurements, due to the small size, the high sensitivity to ionizing radiation and the tissue-equivalent composition, LiF thermoluminescence dosimeters (TLD) are well-suited for out-of-field dose measurements. However, the photon energy variation of the stray dose leads to systematic dose errors caused by the variation in response with radiation energy of the TLDs. We present a dosimeter which automatically corrects for the energy variation of the measured photons by combining LiF:Mg,Ti (TLD100) and LiF:Mg,Cu,P (TLD100H) chips. METHODS The response with radiation energy of TLD100 and TLD100H compared to 60Co was taken from the literature. For the measurement, a TLD100H was placed on top of a TLD100 chip. The dose ratio between the TLD100 and TLD100H, combined with the ratio of the response curves was used to determine the mean energy. With the energy, the individual correction factors for TLD100 and TLD100H could be found. The accuracy in determining the in- and out-of-field dose for a nominal beam energy of 6MV using the double-TLD unit was evaluated by an end-to-end measurement. Furthermore, published Monte Carlo (M.C.) simulations of the mean photon energy for brachytherapy sources, stray radiation of a treatment machine and cone beam CT (CBCT) were compared to the measured mean energies. Finally, the photon energy distribution in an Alderson phantom was measured for different treatment techniques applied with a linear accelerator. Additionally, a treatment plan was measured with a cobalt machine combined with an MRI. RESULTS For external radiotherapy, the presented double-TLD unit showed a relative type A uncertainty in doses of -1%±2% at the two standard deviation level compared to an ionization chamber. The type A uncertainty in dose was in agreement with the theoretically calculated type B uncertainty. The measured energies for brachytherapy sources, stray radiation of a treatment machine and CBCT imaging were in agreement with M.C. simulations. A shift in energy with increasing distance to the isocenter was noticed for the various treatment plans measured with the Alderson phantom. The calculated type B uncertainties in energy were in line with the experimentally evaluated type A uncertainties. CONCLUSION The double-TLD unit is able to predict the photon energy of scatter radiation in external radiotherapy, X-ray imagine and brachytherapy sources. For external radiotherapy, the individual energy correction factors enabled a more accurate dose determination compared to conventional TLD measurements.
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Affiliation(s)
- Pascal Hauri
- Department of Physics, University of Zurich, Zurich, Switzerland; Radiotherapy Hirslanden, Hirslanden Medical Center, Aarau, Switzerland.
| | - Uwe Schneider
- Department of Physics, University of Zurich, Zurich, Switzerland; Radiotherapy Hirslanden, Hirslanden Medical Center, Aarau, Switzerland
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Abstract
BACKGROUND Timely identification of patients in need of palliative care is especially challenging in a geriatric population because of prognostic uncertainty. The Supportive and Palliative Care Indicators Tool (SPICT™) aims at facilitating this identification, yet has not been validated in a geriatric population. OBJECTIVE This study validates the SPICT in a geriatric patient population admitted to the hospital. DESIGN This is a retrospective cohort study. SETTING Subject were patients admitted to the acute geriatric ward of a Belgian university hospital between January 1 and June 30, 2014. MEASUREMENTS Data including demographics, functional status, comorbidities, treatment limitation decision (TLD), and one-year mortality were collected. SPICT was measured retrospectively by an independent assessor. RESULTS Out of 435 included patients, 54.7% had a positive SPICT, using a cut-off value of 2 for the general indicators and a cut-off value of 1 for the clinical questions. SPICT-positive patients were older (p = 0.033), more frequently male (p = 0.028), and had more comorbidities (p = 0.015) than SPICT-negative patients. The overall one-year mortality was 32.2%, 48.7% in SPICT-positive patients, and 11.5% in SPICT-negative patients (p < 0.001). SPICT predicted one-year mortality with a sensitivity of 0.841 and a specificity of 0.579. The area under the curve of the general indicators (0.758) and the clinical indicators of SPICT (0.748) did not differ (p = 0.638). In 71.4% of SPICT-positive cases, a TLD was present versus 26.9% in SPICT-negative cases (p < 0.001). CONCLUSION SPICT seems to be valuable for identifying geriatric patients in need of palliative care as it demonstrates significant association with one-year mortality and with clinical survival predictions of experienced geriatricians, as reflected by TLDs given.
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Affiliation(s)
- Reine De Bock
- 1 Faculty of Medicine and Health Science, Ghent University , Ghent, Belgium
| | | | - Ruth Piers
- 2 Department of Geriatrics, Ghent University Hospital , Ghent, Belgium
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Soliman HA, Hassan MA, Esmat E, Sadek AM, Maghraby AM. Thermally enhanced TLD output: Impacts on the response curve. Appl Radiat Isot 2017; 125:60-5. [PMID: 28411535 DOI: 10.1016/j.apradiso.2017.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 03/25/2017] [Accepted: 04/03/2017] [Indexed: 11/23/2022]
Abstract
Pre-irradiation background reading of thermoluminescent LiF dosimeters results in severe changes in the glow curve qualitatively and quantitatively. Current work focuses on the possible changes in the response of TLD-700 dosimeters after this effect. This work examines changes in the level of the glow curve as a whole and on the level of individual peaks as well. It was found that the response of TLD-700 dosimeters has increased by factors ranging from 20% to 44% in terms of area under the glow curve. Changes in individual peaks were examined by performing deconvolution for the glow curves. Results confirmed that the response due to such effect is not uniform over the studied temperature range and each individual peak has its own behavior either in terms of peak area or peak intensity. It was observed that the third peak (P3) leads these changes as the change in its area after being exposed to this thermally enhanced thermoluminescence output (TETO) effect was in the range from 4.1 to 3.0 folds compared to the corresponding values obtained without reading the background prior to irradiation. Peak intensity possesses similar behavior where peaks P2 and P4 are following to P3 in their response, the rest of peaks are either neutral or have negative response to TETO. Response curves of each deconvoluted peak in terms of peak area and maximum intensity are analyzed over the range (0.05-30) Gy and discussed in details.
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Lonski P, Keehan S, Siva S, Pham D, Franich RD, Taylor ML, Kron T. Out-of-field in vivo dosimetry using TLD in SABR for primary kidney cancer involving mixed photon fields. Phys Med 2017; 37:9-15. [PMID: 28535921 DOI: 10.1016/j.ejmp.2017.03.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 03/21/2017] [Accepted: 03/27/2017] [Indexed: 11/20/2022] Open
Abstract
PURPOSE To assess out-of-field dose using three different variants of LiF thermoluminescence dosimeters (TLD) for ten patients who underwent stereotactic ablative body radiotherapy (SABR) for primary renal cell carcinoma (RCC) and compare with treatment planning system (TPS) dose calculations. METHODS AND MATERIALS Thermoluminescent dosimeter (TLD) measurements were conducted at 20, 30, 40 and 50cm from isocentre on ten patients undergoing SABR for primary RCC. Three types of high-sensitivity LiF:Mg,Cu,P TLD material with different 6Li/7Li isotope ratios were used. Patient plans were calculated using Eclipse Anisotropic Analytical Algorithm (AAA) for clinical evaluation and recalculated using Pencil Beam Convolution (PBC) algorithm for comparison. RESULTS Both AAA and PBC showed diminished accuracy for photon doses at increasing distance out-of-field. At 50cm, measured photon dose was 0.3cGy normalised to a 10Gy prescription on average with only small variation across all patients. This is likely due to the leakage component of the out-of-field dose. The 6Li-enriched TLD materials showed increased signal attributable to additional neutron contribution. CONCLUSION LiF:Mg,Cu,P TLD containing 6Li is sensitive enough to measure out-of-field dose 50cm from isocentre however will over-estimate the photon component of out-of-field dose in high energy treatments due to the presence of thermal neutrons. 7Li enriched materials which are insensitive to neutrons are therefore required for accurate photon dosimetry. Neutron signal has been shown here to increase with MUs and is higher for patients treated using certain non coplanar beam arrangements. Further work is required to convert this additional neutron signal to dose.
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Abstract
The Imaging and Radiation Oncology Core QA Center in Houston (IROC-H) performs remote dosimetry audits of more than 20,000 megavoltage photon and electron beams each year. Both a thermoluminescent dosimeter (TLD-100) and optically stimulated luminescent dosimeter (OSLD; nanoDot) system are commissioned for this task, with the OSLD system being predominant due to the more time-efficient read-out process. The measurement apparatus includes 3 TLD or 2 OSLD in an acrylic mini-phantom, which are irradiated by the institution under reference geometry. Dosimetry systems are calibrated based on the signal-to-dose conversion established with reference dosimeters irradiated in a Co-60 beam, using a reference dose of 300 cGy for TLD and 100 cGy for OSLD. The uncertainty in the dose determination is 1.3% for TLD and 1.6% for OSLD at the one sigma level. This accuracy allows for a tolerance of ±5% to be used.
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Affiliation(s)
- P Alvarez
- Department of Radiation Physics, The University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA
| | - S F Kry
- Department of Radiation Physics, The University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA
| | - F Stingo
- Department of Biostatistics and Applied Math, The University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA
| | - D Followill
- Department of Radiation Physics, The University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA
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Öğretici A, Akbaş U, Köksal C, Bilge H. Investigation of conformal and intensity-modulated radiation therapy techniques to determine the absorbed fetal dose in pregnant patients with breast cancer. Med Dosim 2016; 41:95-9. [PMID: 26831923 DOI: 10.1016/j.meddos.2015.10.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 08/27/2015] [Accepted: 10/14/2015] [Indexed: 12/26/2022]
Abstract
The aim of this research was to investigate the fetal doses of pregnant patients undergoing conformal radiotherapy or intensity-modulated radiation therapy (IMRT) for breast cancers. An Alderson Rando phantom was chosen to simulate a pregnant patient with breast cancer who is receiving radiation therapy. This phantom was irradiated using the Varian Clinac DBX 600 system (Varian Medical System, Palo Alto, CA) linear accelerator, according to the standard treatment plans of both three-dimensional conformal radiation therapy (3-D CRT) and IMRT techniques. Thermoluminescent dosimeters were used to measure the irradiated phantom׳s virtually designated uterus area. Thermoluminescent dosimeter measurements (in the phantom) revealed that the mean cumulative fetal dose for 3-D CRT is 1.39cGy and for IMRT it is 8.48cGy, for a pregnant breast cancer woman who received radiation treatment of 50Gy. The fetal dose was confirmed to increase by 70% for 3-D CRT and 40% for IMRT, if it is closer to the irradiated field by 5cm. The mean fetal dose from 3-D CRT is 1.39cGy and IMRT is 8.48cGy, consistent with theoretic calculations. The IMRT technique causes the fetal dose to be 5 times more than that of 3-D CRT. Theoretic knowledge concerning the increase in the peripheral doses as the measurements approached the beam was also practically proven.
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Affiliation(s)
- Akın Öğretici
- Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey.
| | - Uğur Akbaş
- Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey
| | - Canan Köksal
- Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey
| | - Hatice Bilge
- Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey
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Tseng HC, Pan LK, Chen HY, Liu WS, Hsu CC, Chen CY. In vivo evaluating skin doses for lung cancer patients undergoing volumetric modulated arc therapy treatment. Biomed Mater Eng 2015; 26 Suppl 1:S1677-83. [PMID: 26405934 DOI: 10.3233/bme-151467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study is the first to use 10- to 90-kg tissue-equivalent phantoms as patient surrogates to measure peripheral skin doses (Dskin) in lung cancer treatment through Volumetric Modulated Arc Therapy of the Axesse linac. Five tissue-equivalent and Rando phantoms were used to simulate lung cancer patients using the thermoluminescent dosimetry (TLD-100H) approach. TLD-100H was calibrated using 6 MV photons coming from the Axesse linac. Then it was inserted into phantom positions that closely corresponded with the position of the represented organs and tissues. TLDs were measured using the Harshaw 3500 TLD reader. The ICRP 60 evaluated the mean Dskin to the lung cancer for 1 fraction (7 Gy) undergoing VMAT. The Dskin of these phantoms ranged from 0.51±0.08 (10-kg) to 0.22±0.03 (90-kg) mSv/Gy. Each experiment examined the relationship between the Dskin and the distance from the treatment field. These revealed strong variations in positions close to the tumor center. The correlation between Dskin and body weight was Dskin (mSv) = -0.0034x + 0.5296, where x was phantom's weight in kg. R2 is equal to 0.9788. This equation can be used to derive an equation for lung cancer in males. Finally, the results are compared to other published research. These findings are pertinent to patients, physicians, radiologists, and the public.
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Affiliation(s)
- Hsien-Chun Tseng
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Taiwan, Republic of China.,School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China
| | - Lung-Kang Pan
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung 40609, Taiwan, Republic of China
| | - Hsin-Yu Chen
- School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China
| | - Wen-Shan Liu
- Department of Radiation Oncology, Kaohsiung Veterans Geeral Hospital, Kaohsiung 81362, Taiwan, Republic of China
| | - Chang-Chieh Hsu
- School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China.,Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, 11221 Taiwan, Republic of China
| | - Chien-Yi Chen
- School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China
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Pooya SMH, Dashtipour MR, Enferadi A, Orouji T. Public exposure due to external gamma background radiation in boundary areas of Iran. J Environ Radioact 2015; 147:97-99. [PMID: 26057985 DOI: 10.1016/j.jenvrad.2015.05.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/15/2015] [Accepted: 05/23/2015] [Indexed: 06/04/2023]
Abstract
A monitoring program in boundary areas of a country is an appropriate way to indicate the level of public exposure. In this research, gamma background radiation was measured using TL dosimeters at 12 boundary areas as well as in the capital city of Iran during the period 2010 to 2011. The measurements were carried out in semi-annual time intervals from January to June and July to December in each year. The maximum average dose equivalent value measured was approximately 70 μSv/month for Tehran city. Also, the average dose values obtained were less than 40 μSv/month for all the cities located at the sea level except that of high level natural radiation area of Ramsar, and more than 55 μSv/month for the higher elevation cities. The public exposure due to ambient gamma dose equivalent in Iran is within the levels reported by UNSCEAR.
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Affiliation(s)
- S M Hosseini Pooya
- Nuclear Safety and Radiological Protection Research Department, Nuclear Science and Technology Research Institute, Tehran, Iran.
| | | | - A Enferadi
- Iran Nuclear Regulatory Authority, Tehran, Iran
| | - T Orouji
- Iran Nuclear Regulatory Authority, Tehran, Iran
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Abstract
The primary mechanisms by which bacteria lose viability when deprived of thymine have been elusive for over half a century. Early research focused on stalled replication forks and the deleterious effects of uracil incorporation into DNA from thymidine-deficient nucleotide pools. The initiation of the replication cycle and origin-proximal DNA degradation during thymine starvation have now been quantified via whole-genome microarrays and other approaches. These advances have fostered innovative models and informative experiments in bacteria since this topic was last reviewed. Given that thymineless death is similar in mammalian cells and that certain antibacterial and chemotherapeutic drugs elicit thymine deficiency, a mechanistic understanding of this phenomenon might have valuable biomedical applications.
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Affiliation(s)
- Arkady Khodursky
- Biotechnology Institute and Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, Minnesota 55108;
| | - Elena C Guzmán
- Departamento de Bioquímica Biología Molecular y Genética, Universidad de Extremadura, 06071 Badajoz, Spain;
| | - Philip C Hanawalt
- Department of Biology, Stanford University, Stanford, California 94305;
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Gambarini G, Artuso E, Giove D, Felisi M, Volpe L, Barcaglioni L, Agosteo S, Garlati L, Pola A, Klupak V, Viererbl L, Vins M, Marek M. Study of suitability of Fricke-gel-layer dosimeters for in-air measurements to characterise epithermal/thermal neutron beams for NCT. Appl Radiat Isot 2015; 106:145-50. [PMID: 26249744 DOI: 10.1016/j.apradiso.2015.07.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 06/15/2015] [Accepted: 07/25/2015] [Indexed: 11/30/2022]
Abstract
The reliability of Fricke gel dosimeters in form of layers for measurements aimed at the characterization of epithermal neutron beams has been studied. By means of dosimeters of different isotopic composition (standard, containing (10)B or prepared with heavy water) placed against the collimator exit, the spatial distribution of gamma and fast neutron doses and of thermal neutron fluence are attained. In order to investigate the accuracy of the results obtained with in-air measurements, suitable MC simulations have been developed and experimental measurements have been performed utilizing Fricke gel dosimeters, thermoluminescence detectors and activation foils. The studies were related to the epithermal beam designed for BNCT irradiations at the research reactor LVR-15 (Řež). The results of calculation and measurements have revealed good consistency of gamma dose and fast neutron 2D distributions obtained with gel dosimeters in form of layers. In contrast, noticeable modification of thermal neutron fluence is caused by the neutron moderation produced by the dosimeter material. Fricke gel dosimeters in thin cylinders, with diameter not greater than 3mm, have proved to give good results for thermal neutron profiling. For greater accuracy of all results, a better knowledge of the dependence of gel dosimeter sensitivity on radiation LET is needed.
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Affiliation(s)
- G Gambarini
- Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy.
| | - E Artuso
- Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy
| | - D Giove
- Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy
| | - M Felisi
- Department of Physics, Università degli Studi di Milano, Milan, Italy
| | - L Volpe
- Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy
| | - L Barcaglioni
- Energy Department, Politecnico di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy
| | - S Agosteo
- Energy Department, Politecnico di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy
| | - L Garlati
- Energy Department, Politecnico di Milano, Milan, Italy
| | - A Pola
- Energy Department, Politecnico di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy
| | - V Klupak
- Department of Neutron Physics, Research Centre Řež, Czech Republic
| | - L Viererbl
- Department of Neutron Physics, Research Centre Řež, Czech Republic
| | - M Vins
- Department of Neutron Physics, Research Centre Řež, Czech Republic
| | - M Marek
- Department of Neutron Physics, Research Centre Řež, Czech Republic
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HosseiniAliabadi SJ, Hosseini Pooya SM, Afarideh H, Mianji F. Improvement of Accuracy in Environmental Dosimetry by TLD Cards Using Three-dimensional Calibration Method. J Biomed Phys Eng 2015; 5:49-52. [PMID: 26157729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Indexed: 11/23/2022]
Abstract
INTRODUCTION The angular dependency of response for TLD cards may cause deviation from its true value on the results of environmental dosimetry, since TLDs may be exposed to radiation at different angles of incidence from the surrounding area. OBJECTIVE A 3D setting of TLD cards has been calibrated isotropically in a standard radiation field to evaluate the improvement of the accuracy of measurement for environmental dosimetry. METHOD Three personal TLD cards were rectangularly placed in a cylindrical holder, and calibrated using 1D and 3D calibration methods. Then, the dosimeter has been used simultaneously with a reference instrument in a real radiation field measuring the accumulated dose within a time interval. RESULT The results show that the accuracy of measurement has been improved by 6.5% using 3D calibration factor in comparison with that of normal 1D calibration method. CONCLUSION This system can be utilized in large scale environmental monitoring with a higher accuracy.
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Abstract
Thymineless death (TLD) in bacteria has been a focus of research for decades. Nevertheless, the advances in the last 5 years, with Escherichia coli as the model organism, have been outstanding. Independent research groups have presented compelling results that establish that the initiation of chromosome replication under thymine starvation is a key element in the scenario of TLD. Here we review the experimental results linking the initiation of replication to the lethality under thymine starvation and the proposed mechanisms by which TLD occurs. The concept of this relationship was ‘in the air,’ but approaches were not sufficiently developed to demonstrate the crucial role of DNA initiation in TLD. Genome-wide marker frequency analysis and Two Dimensional agarose gel electrophoresis have been critical methods employed to reveal that initiation events and the degradation of the oriC region occur during thymine starvation. The relationships between these events and TLD have established them to be the main underlying causes of the lethality under thymine starvation. Furthermore, we summarize additional important findings from the study of different mutant strains, which support the idea that the initiation of chromosomal replication and TLD are connected.
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Affiliation(s)
- Elena C Guzmán
- Departamento de Bioquímica Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura Badajoz, Spain
| | - Carmen M Martín
- Departamento de Bioquímica Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura Badajoz, Spain
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Tseng HC, Liu WS, Tsai HH, Chu HY, Lin JB, Chen CY. Radiation dose for normal organs by helical tomotherapy for lung cancer. Appl Radiat Isot 2015; 102:35-41. [PMID: 25935507 DOI: 10.1016/j.apradiso.2015.04.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 04/03/2015] [Accepted: 04/13/2015] [Indexed: 11/19/2022]
Abstract
This study derived a simple equation of effective dose (E) versus normal organ of patients with varying body weights undergoing lung cancer treatment of helical tomotherapy (TOMO). Five tissue-equivalent and Rando phantoms were used to simulate lung cancer patients. This study then measured E and equivalent dose of organ or tissues (DT) using thermoluminescent dosimetry (TLD-100H). The TLD-100H was calibrated using TOMO 6MV photons, then inserted into phantom positions that closely corresponded with the position of the represented organs and tissues. Both E and DT were evaluated by ICRP 103. Peripheral doses varied markedly at positions close to the tumor center. The maximum statistical and total errors were 16.7-22.3%. This analytical result indicates that E of Rando and tissue-equivalent phantoms was in the ranged of 9.44±1.70 (10kg) to 4.58±0.83 (90kg)mSv/Gy. Notably, E decreased exponentially as phantom weight increased. Peripheral doses were also evaluated by TLD as a function of distance from the tumor center. Finally, experimental results are compared with those in literature. These findings will prove useful to patients, physicians, radiologists, and the public.
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Affiliation(s)
- Hsien-Chun Tseng
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Chung Shan Medical University, Taichung 40201,Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China; School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China
| | - Wen-Shan Liu
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Chung Shan Medical University, Taichung 40201,Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China; School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China; Department of Radiation Oncology, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan, Republic of China
| | - Hsiao-Han Tsai
- School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China; Department of Radiology,Taipei Medical University- Shuang Ho Hospital, New Taipei City 23561, Taiwan, Republic of China
| | - Hsin-Yi Chu
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Chung Shan Medical University, Taichung 40201,Taiwan, Republic of China
| | - Jye-Bin Lin
- Department of Medical Image,Chung Shan Medical University Hospital, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China
| | - Chien-Yi Chen
- School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung 40201, Taiwan, Republic of China.
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Alzimami K, Sulieman A, Babikir E, Alsafi K, Alkhorayef M, Omer H. Estimation of effective dose during hystrosalpingography procedures in certain hospitals in Sudan. Appl Radiat Isot 2015; 100:2-6. [PMID: 25752707 DOI: 10.1016/j.apradiso.2015.02.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 02/08/2015] [Accepted: 02/09/2015] [Indexed: 11/18/2022]
Abstract
The aims of this study were to measure the patients' entrance surface air kerma doses (ESAK), effective doses and to compare practices between different hospitals in Sudan. ESAK were measured for patient using calibrated thermo luminance dosimeters (TLDs, GR200A). Effective doses were estimated using National radiological Protection Board (NRPB) software. This study was conducted in five radiological departments: Two Teaching Hospitals (A and D), two private hospitals (B and C) and one University Hospital (E). The mean ESAK was 20.1mGy, 28.9mGy, 13.6mGy, 17.5mGy, 35.7mGy for hospitals A, B, C, D, and E, respectively. The mean effective dose was 2.4mSv, 3.5mSv, 1.6mSv, 2.1mSv and 4.3mSv in the same order. The study showed wide variations in the ESDs with three of the hospitals having values above the internationally reported values.
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Affiliation(s)
- K Alzimami
- Radiological Sciences Department, College of Applied Medical Sciences, King Saud University, P. O. Box 10219, Riyadh 11433, Saudi Arabia.
| | - A Sulieman
- Salman bin Abdulaziz University, College of Applied Medical Sciences, Radiology and Medical Imaging Department, P.O. Box 422, Alkharj, Saudi Arabia; Basic Science Department, College of Medical Radiologic Sciences, Sudan University of Science and Technology, P.O. Box 1908, Khartoum, Sudan
| | - E Babikir
- Radiological Sciences Department, College of Applied Medical Sciences, King Saud University, P. O. Box 10219, Riyadh 11433, Saudi Arabia
| | - K Alsafi
- Radiology Department, School of Medicine, King Abdulaziz University, Saudi Arabia
| | - M Alkhorayef
- Radiological Sciences Department, College of Applied Medical Sciences, King Saud University, P. O. Box 10219, Riyadh 11433, Saudi Arabia
| | - Hiba Omer
- Faculty of Medicine, Dammam University, Dammam, Saudi Arabia
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