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Vassileva J, Rehani M, Kostova-Lefterova D, Al-Naemi HM, Al Suwaidi JS, Arandjic D, Bashier EHO, Kodlulovich Renha S, El-Nachef L, Aguilar JG, Gershan V, Gershkevitsh E, Gruppetta E, Hustuc A, Jauhari A, Kharita MH, Khelassi-Toutaoui N, Khosravi HR, Khoury H, Kralik I, Mahere S, Mazuoliene J, Mora P, Muhogora W, Muthuvelu P, Nikodemova D, Novak L, Pallewatte A, Pekarovič D, Shaaban M, Shelly E, Stepanyan K, Thelsy N, Visrutaratna P, Zaman A. A study to establish international diagnostic reference levels for paediatric computed tomography. Radiat Prot Dosimetry 2015; 165:70-80. [PMID: 25836685 DOI: 10.1093/rpd/ncv116] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The article reports results from the largest international dose survey in paediatric computed tomography (CT) in 32 countries and proposes international diagnostic reference levels (DRLs) in terms of computed tomography dose index (CTDI vol) and dose length product (DLP). It also assesses whether mean or median values of individual facilities should be used. A total of 6115 individual patient data were recorded among four age groups: <1 y, >1-5 y, >5-10 y and >10-15 y. CTDIw, CTDI vol and DLP from the CT console were recorded in dedicated forms together with patient data and technical parameters. Statistical analysis was performed, and international DRLs were established at rounded 75th percentile values of distribution of median values from all CT facilities. The study presents evidence in favour of using median rather than mean of patient dose indices as the representative of typical local dose in a facility, and for establishing DRLs as third quartile of median values. International DRLs were established for paediatric CT examinations for routine head, chest and abdomen in the four age groups. DRLs for CTDI vol are similar to the reference values from other published reports, with some differences for chest and abdomen CT. Higher variations were observed between DLP values, based on a survey of whole multi-phase exams. It may be noted that other studies in literature were based on single phase only. DRLs reported in this article can be used in countries without sufficient medical physics support to identify non-optimised practice. Recommendations to improve the accuracy and importance of future surveys are provided.
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Affiliation(s)
- J Vassileva
- International Atomic Energy Agency, Vienna, Austria
| | - M Rehani
- Harvard Medical School and Massachusetts General Hospital, Boston, USA
| | | | | | - J S Al Suwaidi
- Medical Education Department, Dubai Health Authority, Dubai, UAE
| | - D Arandjic
- Radiation Protection Department, Vinca Institute of Nuclear Sciences, Belgrade, Serbia
| | | | | | - L El-Nachef
- Lebanese Atomic Eneregy Commission, Beirut, Lebanon
| | - J G Aguilar
- National Institute for Nuclear Research, Carretera Mexico-Toluca, La Marquesa, Ocoyoacac, Mexico
| | - V Gershan
- Institute of Physics, Ss Cyril and Methodius University, Skopje, The former Yugoslav Republic of Macedonia
| | | | | | - A Hustuc
- National Centre of Public Health, Chisinau, Republic of Moldova
| | - A Jauhari
- Pusat Kajian Radiografi dan Imajing, Depok, Indonesia
| | | | - N Khelassi-Toutaoui
- Département de Physique Médicale, Centre de Recherche Nucléaire D'Alger, Algiers, Algiers
| | - H R Khosravi
- National Radiation Protection Department, Iranian Nuclear Regulatory Authority, Tehran, Iran
| | - H Khoury
- Universidade Federal de Pernambuco, Cidade Universitaria, Recife PE, Brazil
| | - I Kralik
- State Office for Radiological and Nuclear Safety, Zagreb, Croatia
| | - S Mahere
- Children Clinical University Hospital, Riga, Latvia
| | - J Mazuoliene
- Hospital of Lithuanian University of Health Science Kauno Klinikos, Kaunas, Lithuania
| | - P Mora
- Centro de Investigación en Ciencias Atómicas, Nucleares y Moleculares, Universidad de Costa Rica, San José, Costa Rica
| | - W Muhogora
- Tanzania Atomic Energy Commission, Arusha, Tanzania
| | - P Muthuvelu
- Ministry of Health Malaysia, Putrajaya Wilayah Persekutuan, Malaysia
| | - D Nikodemova
- Slovak Medical University, Limbova, Bratislava, Slovakia
| | - L Novak
- National Radiation Protection Institute, Prague, Czech Republic
| | - A Pallewatte
- Department of Radiology, The National Hospital of Sri Lanka, Colombo, Sri Lanka
| | - D Pekarovič
- Clinical Radiology Institute, University Medical Center, Ljubljana, Slovenia
| | - M Shaaban
- Al-Sabah Hospital, Kuwait City, Kuwait
| | - E Shelly
- Ministry of Health, Medical Technology and Infrastructure Administration, Jerusalem, Israel
| | - K Stepanyan
- Research Center of Radiation Medicine and Burns, Yerevan, Armenia
| | - N Thelsy
- Radiologist Ministry of Health, Yangon, Myanmar
| | - P Visrutaratna
- Faculty of Medicine, Department of Radiology, Chiang Mai University, Chiang Mai, Thailand
| | - A Zaman
- Institute of Nuclear Medicine and Oncology, PAEC, Lahore, Pakistan
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Saeedzadeh E, Sarkar S, Abbaspour Tehrani-Fard A, Ay MR, Khosravi HR, Loudos G. 3D calculation of absorbed dose for 131I-targeted radiotherapy: a Monte Carlo study. Radiat Prot Dosimetry 2012; 150:298-305. [PMID: 22069233 DOI: 10.1093/rpd/ncr411] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Various methods, such as those developed by the Medical Internal Radiation Dosimetry (MIRD) Committee of the Society of Nuclear Medicine or employing dose point kernels, have been applied to the radiation dosimetry of (131)I radionuclide therapy. However, studies have not shown a strong relationship between tumour absorbed dose and its overall therapeutic response, probably due in part to inaccuracies in activity and dose estimation. In the current study, the GATE Monte Carlo computer code was used to facilitate voxel-level radiation dosimetry for organ activities measured in an (131)I-treated thyroid cancer patient. This approach allows incorporation of the size, shape and composition of organs (in the current study, in the Zubal anthropomorphic phantom) and intra-organ and intra-tumour inhomogeneities in the activity distributions. The total activities of the tumours and their heterogeneous distributions were measured from the SPECT images to calculate the dose maps. For investigating the effect of activity distribution on dose distribution, a hypothetical homogeneous distribution of the same total activity was considered in the tumours. It was observed that the tumour mean absorbed dose rates per unit cumulated activity were 0.65E-5 and 0.61E-5 mGY MBq(-1) s(-1) for the uniform and non-uniform distributions in the tumour, respectively, which do not differ considerably. However, the dose-volume histograms (DVH) show that the tumour non-uniform activity distribution decreases the absorbed dose to portions of the tumour volume. In such a case, it can be misleading to quote the mean or maximum absorbed dose, because overall response is likely limited by the tumour volume that receives low (i.e. non-cytocidal) doses. Three-dimensional radiation dosimetry, and calculation of tumour DVHs, may lead to the derivation of clinically reliable dose-response relationships and therefore may ultimately improve treatment planning as well as response assessment for radionuclide therapy.
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Affiliation(s)
- E Saeedzadeh
- Department of Radiomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
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Ahmadi Jeshvaghane N, Paydar R, Fasaei B, Pakneyat A, Karamloo A, Deevband MR, Khosravi HR. Criteria for patient release according to external dose rate and residual activity in patients treated with 131I-sodium iodide in Iran. Radiat Prot Dosimetry 2011; 147:264-266. [PMID: 21757441 DOI: 10.1093/rpd/ncr305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
External dose rate (ED) and residual activity (RA) of patients treated with (131)I sodium iodide are two main factors, to consider before release of patients. In this study, six nuclear medicine centres out of total seven centres in Iran were selected and measurements have been done on 330 patients. ED of patients was measured by physicists of the centres for 6 months (May-November 2009) at a 1 m distance from the thyroid of each patient on the first, second and third days after administration by a calibrated survey meter. The maximum and minimum values of ED were 21 (SD = 18) and 11 (SD = 4) µSv h(-1), respectively. Furthermore, the maximum and minimum values of RA during release of patient were 720 and 250 MBq, respectively. According to the study, we recommend a release activity limit of 500 MBq (14 mCi) or a dose rate level of 20 µSv h(-1) at 1 m from the patient to be set instead of a release activity limit of 1100 MBq (30 mCi) as it is now for the country.
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Affiliation(s)
- N Ahmadi Jeshvaghane
- National Radiation Protection Department, Iranian Nuclear Regulatory Authority, PO Box 14155-4494, Tehran, Iran.
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Paknyat A, Samarin ERP, Jeshvaghane NA, Paydar R, Fasaei B, Karamloo A, Khosravi HR, Deevband MR. Evaluation of patient dose in some mammography centres in Iran. Radiat Prot Dosimetry 2011; 147:192-195. [PMID: 21816723 DOI: 10.1093/rpd/ncr322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
High diagnostic sensitivity and specificity while maintaining the least dose to the patient is the ideal mammography. The objective of this work was to evaluate patient dose and image quality of mammograms to propose corrective actions. The image quality for 1242 patient in 7 mammography facilities in Tehran city was evaluated based on selected image quality criteria using a three-point scale. Clinical image quality, the entrance surface air kerma, the average glandular dose and optical density of films for standard PMMA phantom of 4.5 cm thickness were evaluated. The results showed that up to 72 % of mammograms were in good condition to be diagnosed, and only about 3.4 % of the images were unacceptable or with suboptimal quality. The entrance surface air kerma values were in the range of 3.8-10.5 mGy, average glandular dose 0.5-1.8 mGy and optical density of films 0.74-2.03. The image quality evaluation after correction actions, periodic image quality evaluation and using the correct equipment certainly will improve patient dose.
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Affiliation(s)
- A Paknyat
- Nation Radiation Protection Department, Iranian Nuclear Regulatory Authority, PO Box 14155-4494, Tehran, Iran.
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Orouji T, Hosseini Pooya SM, Jafarizadeh M, Khosravi HR, Rais Mohammad H. Doses to the scanned individual and to the operator from an X-ray body scanner system. Radiat Prot Dosimetry 2011; 147:227-229. [PMID: 21831862 DOI: 10.1093/rpd/ncr343] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The X-ray body scanner (BS) is going to find common use as a body-checking equipment at the entrance borders of countries, to find illicit drugs or forbidden items which have been hidden inside the body cavities, or attached to the body parts of the passengers. Considering the tissue weighting factors of the sensitive organs, the total effective dose due to the scanning by the system was estimated to be 3.8 µSv per scan. The ambient dose equivalent rates within the distance range of 300-40 cm from the X-ray generator were measured to be 4.5 up to 50 µSv h(-1). It is concluded that, in general, BS systems could be a safe device for the operators and people who are being scanned. But using such systems should be justified for everybody and special care should be taken for children and pregnant ladies.
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Affiliation(s)
- T Orouji
- National Radiation Protection Department, Iran Nuclear Regulatory Authority, PO Box 14155-1339, Tehran, Iran
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