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Cewe P, Vorbau R, Omar A, Elmi-Terander A, Edström E. Radiation distribution in a hybrid operating room, utilizing different X-ray imaging systems: investigations to minimize occupational exposure. J Neurointerv Surg 2021; 14:1139-1144. [PMID: 34750111 PMCID: PMC9606514 DOI: 10.1136/neurintsurg-2021-018220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/31/2021] [Indexed: 01/10/2023]
Abstract
Objectives To reduce occupational radiation exposure in a hybrid operating room (OR) used for three-dimensional (3D) image guided spine procedures. The effects of staff positioning, different X-ray imaging systems, and freestanding radiation protection shields (RPSs) were considered. Methods An anthropomorphic phantom was imaged with a robotic ceiling mounted hybrid OR C-arm cone beam CT (hCBCT), a mobile O-arm CBCT (oCBCT), and a mobile two-dimensional C-arm fluoroscopy system. The resulting scatter doses were measured at different positions in the hybrid OR using active personal dosimeters and an ionization chamber. Two types of RPSs were evaluated. Results Using the hCBCT system instead of the oCBCT system reduced the occupational radiation dose on average by 22%. At 200 cm from the phantom, scatter doses from the hCBCT were 27% lower compared with the oCBCT. One rotational acquisition with hCBCT or oCBCT corresponded to 12 or 16 min of fluoroscopy with the C-arm, respectively. The scatter dose decreased by more than 90% behind an RPS. However, the protection was slightly less effective at 60 cm behind the RPS, due to tertiary scatter from the surroundings. Conclusions For 3D image guided spine procedures in the hybrid OR, occupational radiation exposure is lowered by using hCBCT rather than oCBCT. Radiation exposure can also be decreased by optimal staff positioning in the OR, considering distance to the source and positioning relative to the walls, ceiling, and RPS. In this setting and workflow, staff can use RPSs instead of heavy aprons during intraoperative CBCT imaging, to achieve effective whole body dose reduction with improved comfort.
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Affiliation(s)
- Paulina Cewe
- Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden .,Department of Radiology, Karolinska University Hospital, Stockholm, Sweden
| | - Robert Vorbau
- Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Artur Omar
- Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Adrian Elmi-Terander
- Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Neurosurgery, Karolinska University Hospital, Stockholm, Sweden
| | - Erik Edström
- Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Neurosurgery, Karolinska University Hospital, Stockholm, Sweden
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Eder H, Seidenbusch M, Oechler LS. TERTIARY X-RADIATION-A PROBLEM FOR STAFF PROTECTION? RADIATION PROTECTION DOSIMETRY 2020; 189:304-311. [PMID: 32221614 DOI: 10.1093/rpd/ncaa043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 02/29/2020] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
The influence of tertiary x-radiation on the radiological staff is widely unknown. Tertiary radiation is caused as the scattered radiation of the patient impacts the walls, floor, ceiling and surrounding air. The question that arises is does tertiary x-radiation provide a relevant contribution to the staff doses. The impact of tertiary radiation was investigated by means of measurements of the personal dose equivalent Hp(10) on an anthropomorphic Alderson Rando male phantom and also on operators/assistants staying in clinical practice. Further, the protective effect of lead foils, especially under tertiary radiation was also investigated. Correlations could be derived for clinical angiographic/interventional procedures between dose area products (DAPs) and dose length products (DLPs) vs. dorsal doses of staff persons. Generally, the staff doses that are a result of tertiary radiation depend on the x-ray energy and range from 0.15 to 0.55% of the scattered radiation impact caused by irradiation of the patient. Hence, a back panel with 0.125-mm lead equivalent is sufficient to protect the staff from tertiary radiation created within the room environment.
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Affiliation(s)
- H Eder
- Formerly Bavarian Environment Agency, Am Stadtpark 43, 81243 Munich, Germany
| | - M Seidenbusch
- Department of Radiology, Paediatric Radiology, Dr. v. Hauner's Children's Hospital University of Munich, Lindwurmstr. 4, 80337 München, Germany
| | - L S Oechler
- Institute for Diagnostic and Interventional Radiology, University Hospital Klinikum r. d. Isar, Ismaninger Str. 22, 81675 Munich, Germany
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Bjarnason TA, Rees R, Kainz J, Le LH, Stewart EE, Preston B, Elbakri I, Fife IAJ, Lee TY, Gagnon IMB, Arsenault C, Therrien P, Kendall E, Tonkopi E, Cottreau M, Aldrich JE. COMP Report: A survey of radiation safety regulations for medical imaging x-ray equipment in Canada. J Appl Clin Med Phys 2019; 21:10-19. [PMID: 32915492 PMCID: PMC7075391 DOI: 10.1002/acm2.12708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/09/2019] [Accepted: 08/06/2019] [Indexed: 12/12/2022] Open
Abstract
X‐ray regulations and room design methodology vary widely across Canada. The Canadian Organization of Medical Physicists (COMP) conducted a survey in 2016/2017 to provide a useful snapshot of existing variations in rules and methodologies for human patient medical imaging facilities. Some jurisdictions no longer have radiation safety regulatory requirements and COMP is concerned that lack of regulatory oversight might erode safe practices. Harmonized standards will facilitate oversight that will ensure continued attention is given to public safety and to control workplace exposure. COMP encourages all Canadian jurisdictions to adopt the dose limits and constraints outlined in Health Canada Safety Code 35 with the codicil that the design standards be updated to those outlined in NCRP 147 and BIR 2012.
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Affiliation(s)
- Thorarin A Bjarnason
- Medical Imaging, Interior Health Authority, Kelowna, BC, Canada.,Radiology, University of British Columbia, Vancouver, BC, Canada.,Physics, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Robert Rees
- Occupational Health & Safety, Yukon Workers' Compensation Health and Safety Board, Whitehorse, YK, Canada
| | - Judy Kainz
- Workers' Safety and Compensation Commission for Northwest Territories and Nunavut, Yellowknife, NT, Canada
| | - Lawrence H Le
- Diagnostic Imaging, Alberta Health Services, Calgary, AB, Canada.,Radiology and Diagnostic Imaging, University of Alberta, Edmonton, AB, Canada
| | - Errol E Stewart
- Diagnostic Imaging, Alberta Health Services, Calgary, AB, Canada
| | - Brent Preston
- Radiation Safety Unit, Government of Saskatchewan, Saskatoon, SK, Canada
| | - Idris Elbakri
- Cancer Care Manitoba, Winnipeg, MB, Canada.,Physics and Astronomy, University of Manitoba, Winnipeg, MB, Canada.,Radiology, University of Manitoba, Winnipeg, MB, Canada
| | - Ingvar A J Fife
- Cancer Care Manitoba, Winnipeg, MB, Canada.,Physics and Astronomy, University of Manitoba, Winnipeg, MB, Canada.,Radiology, University of Manitoba, Winnipeg, MB, Canada
| | - Ting-Yim Lee
- St Joseph's Health Care London, London, ON, Canada.,Lawson Research Institute, London, ON, Canada.,Medical Imaging, Medical Biophysics, Oncology, Robarts Research Institute, University of Western Ontario, London, ON, Canada
| | | | - Clément Arsenault
- Hôpital Dr Georges-L. Dumont, Centre d'Oncologie Dr Léon-Richard, Moncton, NB, Canada
| | - Pierre Therrien
- Therapeutic Physics, Horizon Health Network, Saint-John, NB, Canada
| | - Edward Kendall
- Faculty of Medicine, Memorial University, St John's, NL, Canada
| | - Elena Tonkopi
- Nova Scotia Health Authority, Halifax, NS, Canada.,Diagnostic Radiology, Dalhousie University, Halifax, NS, Canada.,Radiation Oncology, Dalhousie University, Halifax, NS, Canada
| | | | - John E Aldrich
- Radiology, University of British Columbia, Vancouver, BC, Canada
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Bibbo G. Shielding of medical imaging X-ray facilities: a simple and practical method. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2017; 40:925-930. [PMID: 28983885 DOI: 10.1007/s13246-017-0586-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 09/16/2017] [Indexed: 10/18/2022]
Abstract
The most widely accepted method for shielding design of X-ray facilities is that contained in the National Council on Radiation Protection and Measurements Report 147 whereby the computation of the barrier thickness for primary, secondary and leakage radiations is based on the knowledge of the distances from the radiation sources, the assumptions of the clinical workload, and usage and occupancy of adjacent areas. The shielding methodology used in this report is complex. With this methodology, the shielding designers need to make assumptions regarding the use of the X-ray room and the adjoining areas. Different shielding designers may make different assumptions resulting in different shielding requirements for a particular X-ray room. A more simple and practical method is to base the shielding design on the shielding principle used to shield X-ray tube housing to limit the leakage radiation from the X-ray tube. In this case, the shielding requirements of the X-ray room would depend only on the maximum radiation output of the X-ray equipment regardless of workload, usage or occupancy of the adjacent areas of the room. This shielding methodology, which has been used in South Australia since 1985, has proven to be practical and, to my knowledge, has not led to excess shielding of X-ray installations.
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Affiliation(s)
- Giovanni Bibbo
- S A Medical Imaging, Women's and Children's Hospital, 72 King William Road, North Adelaide, SA, 5006, Australia.
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McRobbie D. Both sides now: diagnostic imaging medical physics in two hemispheres. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2017; 40:269-272. [PMID: 28597230 DOI: 10.1007/s13246-017-0561-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Donald McRobbie
- SA Medical Imaging Physics, SA Health, Adelaide, Australia. .,Flinders Medical Centre, Adelaide, Australia. .,School of Physical Sciences, University of Adelaide, Adelaide, Australia. .,Department of Surgery, Imperial College, London, UK.
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Edwards S, Schick D. Monte Carlo Modeling of Computed Tomography Ceiling Scatter for Shielding Calculations. HEALTH PHYSICS 2016; 110:328-341. [PMID: 26910026 DOI: 10.1097/hp.0000000000000474] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Radiation protection for clinical staff and members of the public is of paramount importance, particularly in occupied areas adjacent to computed tomography scanner suites. Increased patient workloads and the adoption of multi-slice scanning systems may make unshielded secondary scatter from ceiling surfaces a significant contributor to dose. The present paper expands upon an existing analytical model for calculating ceiling scatter accounting for variable room geometries and provides calibration data for a range of clinical beam qualities. The practical effect of gantry, false ceiling, and wall attenuation in limiting ceiling scatter is also explored and incorporated into the model. Monte Carlo simulations were used to calibrate the model for scatter from both concrete and lead surfaces. Gantry attenuation experimental data showed an effective blocking of scatter directed toward the ceiling at angles up to 20-30° from the vertical for the scanners examined. The contribution of ceiling scatter from computed tomography operation to the effective dose of individuals in areas surrounding the scanner suite could be significant and therefore should be considered in shielding design according to the proposed analytical model.
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Affiliation(s)
- Stephen Edwards
- *Biomedical Technology Services, The Prince Charles Hospital, Rode Road, Chermside, Queensland, Australia 4032; †Biomedical Technology Services, Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Queensland, Australia 4101
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Martin CJ. Radiation shielding for diagnostic radiology. RADIATION PROTECTION DOSIMETRY 2015; 165:376-381. [PMID: 25813477 DOI: 10.1093/rpd/ncv040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Scattered radiation makes up the majority of the stray radiation field around an X-ray unit. The scatter is linked to the amount of radiation incident on the patient. It can be estimated from quantities used to assess patient dose such as the kerma-area product, and factors have been established linking this to levels of scattered radiation for radiography and fluoroscopy. In radiography shielding against primary radiation is also needed, but in other modalities this is negligible, as the beam is intercepted by the image receptor. In the same way scatter from CT can be quantified in terms of dose-length product, but because of higher radiation levels, exposure to tertiary scatter from ceilings needs to be considered. Transmission requirements are determined from comparisons between calculated radiation levels and agreed dose criteria, taking into account the occupancy of adjacent areas. Thicknesses of shielding material required can then be calculated from simple equations.
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Affiliation(s)
- Colin J Martin
- Department of Clinical Physics and Bio-engineering, University of Glasgow, Glasgow, Scotland, UK
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