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Sakamoto M, Sasaki K, Tsuno H. [Study of Phantom Length Correction for kV-Cone Beam CT Dose Evaluation Method Using Farmer-type Ionization Chamber and Cylindrical Phantom]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2023. [PMID: 37062712 DOI: 10.6009/jjrt.2023-1349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
In this study, we investigated the necessary phantom length for dose evaluation of kV-CBCT mounted on the linear accelerator using a Farmer-type ionization chamber and cylindrical PMMA phantom, which many radiotherapy facilities own. Furthermore, a phantom length correction factor was proposed to compensate for the lack of scattered radiation contributed from the craniocaudal direction due to the inadequate phantom length. The air-absorbed dose at the center of a cylindrical PMMA phantom measured by a Farmer-type ionization chamber indicated that the contribution of scattered radiation saturates when the phantom length is 300 mm or longer. The phantom length correction factor was calculated from an approximate curve showing the relationship of the charge ratio measured using phantoms of 300 mm and 150 mm in length to the X-ray beam width. The air-absorbed dose measured with the 150-mm length phantom, corrected by the phantom length correction factor, showed a 1.61% dose difference from the air-absorbed dose measured with the 300-mm length phantom. In this study, the air-absorbed dose at the center of the phantom could be estimated over a wide X-ray beam width only using a 150-mm length cylindrical PMMA phantom. The method proposed in this study could be used in any radiation therapy facility.
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Affiliation(s)
| | - Koji Sasaki
- Graduate School of Radiological Technology, Gunma Prefectural College of Health Sciences
| | - Hayato Tsuno
- Graduate School of Radiological Technology, Gunma Prefectural College of Health Sciences
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Hung K, Hui L, Yeung AWK, Jacobs R, Leung YY, Bornstein M. An analysis of patient dose received during cone beam computed tomography in relation to scan settings and imaging indications as seen in a dental institution in order to establish institutional diagnostic reference levels. Dentomaxillofac Radiol 2022; 51:20200529. [PMID: 35230883 PMCID: PMC10043612 DOI: 10.1259/dmfr.20200529] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES To investigate the dose-area product (DAP) of cone-beam computed tomography (CBCT) examinations for different scan settings and imaging indications, and to establish institutional diagnostic reference levels (DRLs) for dose optimization. METHODS A retrospective analysis of the DAP values of 3568 CBCT examinations taken from two different devices at the Prince Philip Dental Hospital, Hong Kong between 2016 and 2021 was performed. Patient- (age, gender, and imaging indication) and imaging-related (CBCT device, field-of-view (FOV), and voxel size) were correlated with the DAPs. The indication-oriented third-quartile DAP values were compared with DRLs from the UK, Finland, and Switzerland. The obtained third-quartile DAPs lower than the national DRLs and those for which no national DRLs have been proposed were used to establish institutional DRLs. RESULTS In the investigated CBCTs, the DAP value for large FOV scans was significantly lower than medium/small FOVs. CBCTs with a small voxel size exhibited a significantly higher DAP than those with a medium/large voxel size. CBCTs for endodontic, periodontal, orthodontic, or orthognathic evaluation exhibited a significantly higher DAP than other indications. Twelve indication-oriented institutional DRLs were established and five of them were lower than the national DRLs: third molars (229 mGy×cm2), jaw cysts/tumors (410 mGy×cm2), maxillary sinus pathology (520 mGy×cm2), developing dentition (164 mGy×cm2), and periapical lesions (564 mGy×cm2). CONCLUSIONS CBCT examinations for endodontic, periodontal, orthodontic, or orthognathic evaluation may deliver a higher radiation dose to the patient than other imaging tasks. A periodic review of the patient dose from CBCT imaging and establishment of institutional DRLs for specific clinical settings are needed for monitoring patient dose and to optimize indication-oriented scanning protocols.
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Affiliation(s)
- Kuofeng Hung
- Oral and Maxillofacial Radiology, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - Liuling Hui
- Oral and Maxillofacial Radiology, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - Andy Wai Kan Yeung
- Oral and Maxillofacial Radiology, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - Reinhilde Jacobs
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, University of Leuven and Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Yiu Yan Leung
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - Michael Bornstein
- Oral and Maxillofacial Radiology, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China.,Department of Oral Health & Medicine, University Center for Dental Medicine Basel UZB, University of Basel, Basel, Switzerland
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3
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Sawicki P, Zawadzki PJ, Regulski P. The Impact of Cone-Beam Computed Tomography Exposure Parameters on Peri-Implant Artifacts: A Literature Review. Cureus 2022; 14:e23035. [PMID: 35419219 PMCID: PMC8994570 DOI: 10.7759/cureus.23035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2022] [Indexed: 01/09/2023] Open
Abstract
Cone-beam computed tomography (CBCT) amounts to an excellent diagnostic tool to evaluate the peri-implant bone thickness in all dimensions. Despite the unquestionable advantages of CBCT, potential artifacts around dental implants might disturb the proper assessment of the surrounding structures. The artifacts may mask osseointegration, shallow bone defects, and other types of radiolucency, which make it difficult to establish an early diagnosis of bone loss. Proper diagnosis of bone defect is necessary to decide about surgical intervention. The aim of this literature review is to assess the CBCT exposure causing artifacts on the peri-implant structures. An electronic search of MEDLINE (PubMed) database includes studies published before July 2021 and supplemented by manual research. Clinical, ex vivo, in vitro, and animal studies evaluating the relationship between exposition parameters and occurrence of artifacts around the dental implant in CBCT studies were included. A literature review revealed that kilovoltage, tube current, and field of view may affect the occurrence of artifacts around dental implants, all of which would compromise radiological evaluation. Therefore, it is feasible to reduce the incidence of artifacts and improve the image quality by appropriate modification of the exposure parameters. However, the reduction of artifacts is often associated with a significant increase in radiation exposure; hence, an effort should be made to minimize the radiation dose in line with the ALARA (as low as reasonably achievable) principle.
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Affiliation(s)
- Paweł Sawicki
- Department of Cranio-Maxillofacial Surgery, Oral Surgery, and Implantology, Medical University of Warsaw, Warsaw, POL
| | - Paweł J Zawadzki
- Department of Cranio-Maxillofacial Surgery, Oral Surgery, and Implantology, Medical University of Warsaw, Warsaw, POL
| | - Piotr Regulski
- Department of Dental and Maxillofacial Radiology, Medical University of Warsaw, Warsaw, POL.,Center of Digital Science and Technology, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, POL
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4
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PCXMC cone beam computed tomography dosimetry investigations. Phys Eng Sci Med 2022; 45:205-218. [PMID: 35072895 DOI: 10.1007/s13246-022-01103-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 01/07/2022] [Indexed: 10/19/2022]
Abstract
With cone beam computed tomography (CBCT) in image guided radiation therapy being amongst the most widely used imaging modalities, there has been an increasing interest in quantifying the concomitant dose and risk. Whilst there have been several studies on this topic, there remains a lack of standardisation and knowledge on dose variations and the impact of patient size. Recently, PCXMC (a Monte Carlo simulator) has been used to assess both the concomitant dose and dosimetric impact of patient size variations for CBCT. The scopes of these studies, however, have included only a limited range of imaging manufacturers, protocols, and patient sizes. An approach using PCXMC and MATLAB was developed to enable a generalised method for rapidly quantifying and formulating the concomitant dose as a function of patient size across numerous CBCT vendors and protocols. The method was investigated using the Varian on board imaging 1.6 default pelvis and pelvis spotlight protocols, for 94 adult and paediatric phantoms over 6 age groups with extensive height and mass variations. It was found that dose varies significantly with patient size, as much as doubling and halving the average for patients of lower and higher mass, respectively. These variations, however, can be formulated and accounted for using the method developed, across a wide range of patient sizes for all CBCT vendors and protocols. This will enable the development of a comprehensive catalogue to account for concomitant doses in almost any clinically relevant scenario.
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Dawd JE, Ozsahin DU, Ozsahin I. A Review of Diagnostic Reference Levels in Computed Tomography. Curr Med Imaging 2021; 18:623-632. [PMID: 34517807 DOI: 10.2174/1573405617666210913093839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 11/22/2022]
Abstract
Computed tomography (CT) scanning generate 3-D images of the inside structures of the body by delivering comparatively radiation dose to the patient. This requires high concern of optimization via establishing diagnostic reference level (DRL). DRL values can be estimated based on reference patient percentiles (such as 90th, 75th and 50th) dose distribution. DRL has significant uses in professional judgments by generating harmonized evidence about the radiation dose received by the patient. The primary goal of this review is to assess the practical application of DRL in CT procedures internationally. The main objective of establishing DRLs is to optimize the patient dose and without compromising the image quality in order to obtain adequate diagnostic information. That means inescapability of DRL for a country in medical diagnosis is to reduce the limitation of dose dispersion, to harmonize and expand good practice, to narrow large dispersion of doses, and to create systematic supervision for unwanted radiological doses. The review presents that international records have a wide-range of mean dose distributions due to the variation of exam protocols and technical parameters in use. Hence, this review recommends that each CT health facilities are required exercising careful dose reduction strategies by accounting adequate image quality with sufficient diagnostic information via through follow up of concerned bodies.
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Affiliation(s)
- Jemal Edris Dawd
- Radiation Research and Documentation Department, Ethiopian Radiation Protection Authority, Addis Ababa, Akaki Kality, Ethiopia.,Department of Biomedical Engineering, Near East University, Nicosia/TRNC, Mersin-10, Turkey
| | - Dilber Uzun Ozsahin
- Department of Biomedical Engineering, Near East University, Nicosia/TRNC, Mersin-10, Turkey.,DESAM Institute, Near East University, Nicosia/TRNC, Mersin-10, Turkey.,Medical Diagnostic Imaging Department, College of Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Ilker Ozsahin
- Department of Biomedical Engineering, Near East University, Nicosia/TRNC, Mersin-10, Turkey.,DESAM Institute, Near East University, Nicosia/TRNC, Mersin-10, Turkey.,Brain Health Imaging Institute, Department of Radiology, Weill Cornell Medicine, New York, New York, USA
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6
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Sha X, Jin L, Han J, Li Y, Zhang L, Qi S. Comparison between periapical radiography and cone beam computed tomography for the diagnosis of anterior maxillary trauma in children and adolescents. Dent Traumatol 2021; 38:62-70. [PMID: 34275178 DOI: 10.1111/edt.12706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND/AIMS Under-estimating the damage caused by trauma to the dental structures may delay treatment. Timely and accurate diagnosis remains challenging in clinical practice. Radiography is an important modality for the diagnosis of traumatic injuries. The aim of this study was to compare the efficacy of periapical radiography and cone beam computed tomography for the diagnosis of trauma to the anterior maxillary dentoalveolar region in children and adolescents. MATERIAL AND METHODS Images of patients who underwent both periapical radiography and cone beam computed tomography simultaneously because of trauma to the anterior maxillary region between January 2016 and January 2020 were analyzed retrospectively. Pairwise comparison between the receiver operating characteristic curves was performed to statistically compare the two methods for the diagnosis of crown fractures, root fractures, alveolar bone fractures and luxations, tooth resorption, and periapical radiolucencies. RESULTS A total of 190 patients met the inclusion criteria. There were 120 (63.2%) males and 70 (36.8%) females, with a mean age of 11.1 years (range: 6-17 years). A crown fracture was observed in 144 teeth, while a root fracture was observed in 71 teeth. Alveolar fracture and luxation were observed in 44 incisors. During follow-up, tooth resorption and periapical radiolucencies were observed in 25 and 33 teeth, respectively. Pairwise receiver operating characteristic curve analysis revealed that cone beam computed tomography was significantly superior to periapical radiography for the diagnosis of root fractures, alveolar fractures and luxations, and tooth resorption (p < .05). However, no significant differences were found for the diagnosis of crown fractures and periapical radiolucencies (p > .05). CONCLUSIONS Cone beam computed tomography in the low-dose mode was better for diagnosing root and bone fractures and resorption, but no different to periapical radiographs for crown fractures and periapical radiolucencies in pediatric patients.
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Affiliation(s)
- Xiaoyan Sha
- Department of Oral and Maxillofacial Radiology, School of Stomatology, Capital Medical University, Beijing, China
| | - Ling Jin
- Department of Oral and Maxillofacial Radiology, School of Stomatology, Capital Medical University, Beijing, China
| | - Jianhui Han
- Department of Oral and Maxillofacial Radiology, School of Stomatology, Capital Medical University, Beijing, China
| | - Ying Li
- Department of Pediatric Dentistry, School of Stomatology, Capital Medical University, Beijing, China
| | - Lili Zhang
- Department of Dental Emergency, School of Stomatology, Capital Medical University, Beijing, China
| | - Senrong Qi
- Department of Oral and Maxillofacial Radiology, School of Stomatology, Capital Medical University, Beijing, China
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Siiskonen T, Gallagher A, Ciraj Bjelac O, Novak L, Sans Merce M, Farah J, Dabin J, Malchair F, Knežević Ž, Kortesniemi M. A European perspective on dental cone beam computed tomography systems with a focus on optimisation utilising diagnostic reference levels. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2021; 41:442-451. [PMID: 33461178 DOI: 10.1088/1361-6498/abdd05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
Cone beam computed tomography (CBCT) has been available since the late 1990s for use in dentistry. European legislation requires optimisation of protection and the use of diagnostic reference levels (DRLs) as well as regular quality control (QC) of the imaging devices, which is well outlined in existing international recommendations. Nevertheless, the level of application is not known. Earlier studies have indicated that few European countries have established DRLs and that patient doses (exposure parameters) have not been properly optimised. The EURADOS Working Group 12-Dosimetry in Medical Imaging undertook a survey to identify existing practices in Member States. Questionnaires were developed to identify equipment types, clinical procedures performed, and exposure settings used. The surveys were circulated to 22 countries resulting in 28 responses from 13 countries. Variations were identified in the exposure factors and in the doses delivered to patients for similar clinical indicators. Results confirm that patient doses are still not properly optimised and DRLs are largely not established. There is a need to promote the importance of performing QC testing of dental CBCT equipment and to further optimise patient exposure by establishment and use of DRLs as a part of a continuous optimisation process.
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Affiliation(s)
- Teemu Siiskonen
- Radiation and Nuclear Safety Authority (STUK), P.O. Box 14, FI-00881 Helsinki, Finland
| | | | - Olivera Ciraj Bjelac
- University of Belgrade, Vinca Institute of Nuclear Sciences (VINCA), Belgrade, Serbia
| | - Leos Novak
- National Radiation Protection Institute (NRPI), Prague, Czech Republic
| | - Marta Sans Merce
- Hôpitaux Universitaires de Genève, Genève, Switzerland
- Switzerland and Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | - Jad Farah
- Hôpitaux universitaires Paris-Sud (APHP), Paris Sud University Hospitals, Paris, France
| | - Jérémie Dabin
- Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, BE-2400 Mol, Belgium
| | - Françoise Malchair
- CAATS, 119 Grande Rue, 92310 Sevres, France
- ZEPHYRA, 13 rue Forgeur, 4000 Liege, Belgium
- Centre Hospitalier Universitaire de Liège (CHULg), Sart-Tilman, 4000 Liège, Belgium
| | - Željka Knežević
- Ruđer Bošković Institute (RBI), Bijenicka 54, Zagreb, Croatia
| | - Mika Kortesniemi
- HUS Medical Imaging Center, Helsinki University and Helsinki University Hospital, Haartmaninkatu 4, 00290 Helsinki, Finland
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8
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Kunzendorf B, Naujokat H, Wiltfang J. Indications for 3-D diagnostics and navigation in dental implantology with the focus on radiation exposure: a systematic review. Int J Implant Dent 2021; 7:52. [PMID: 34041613 PMCID: PMC8155130 DOI: 10.1186/s40729-021-00328-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/18/2021] [Indexed: 11/23/2022] Open
Abstract
Background Dental implants are a common restorative method used to replace missing teeth. Implant placement techniques guided by three-dimensional imaging and navigation are becoming more widely available. Objective The present review focused on the following questions: 1. What are the advantages and disadvantages of 2-D versus 3-D imaging in dental implantology? 2. What are the advantages and disadvantages of freehand implant placement in comparison with navigation-guided implant placement? Methods A systematic review was performed, based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. The following libraries were searched for relevant literature: PubMed, Embase, Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF) Online, and the Cochrane Library. The risk of bias was assessed using the Scottish Intercollegiate Guidelines Network (SiGN) checklist. A total of 70 studies were included after screening, and the evidence from these was gathered for review. Results Three-dimensional imaging is advantageous in terms of image quality, and it provides a distortion-free evaluation of the implant site. However, it is also associated with higher costs and increased radiation exposure. Dynamic and static navigation are equal in accuracy and are both more accurate compared with the freehand method. No benefit in terms of implant survival could be demonstrated within the first 5 years for any specific method. Discussion A panoramic X-ray with a reference body often provides sufficient imaging and is the primary method for two-dimensional imaging. Cone beam computed tomography with low-dose protocol settings should be used if three-dimensional imaging is needed. Navigational support should be considered in the event of especially complex cases. Conclusion The guidance technique used for implant placement should be decided on an individual basis. With the increasing availability of three-dimensional imaging, there should also be an increase in awareness of radiation exposure. Supplementary Information The online version contains supplementary material available at 10.1186/s40729-021-00328-9.
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Affiliation(s)
- Burkhard Kunzendorf
- Department of Oral and Maxillofacial Surgery, University Hospital of Schleswig-Holstein, Campus Kiel, Arnold-Heller-Straße 3, 24105, Kiel, Germany.
| | - Hendrik Naujokat
- Department of Oral and Maxillofacial Surgery, University Hospital of Schleswig-Holstein, Campus Kiel, Arnold-Heller-Straße 3, 24105, Kiel, Germany
| | - Jörg Wiltfang
- Department of Oral and Maxillofacial Surgery, University Hospital of Schleswig-Holstein, Campus Kiel, Arnold-Heller-Straße 3, 24105, Kiel, Germany
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High-Dose Fluoroscopically Guided Procedures in Patients: Radiation Management Recommendations for Interventionalists. Cardiovasc Intervent Radiol 2020; 44:849-856. [PMID: 33184693 DOI: 10.1007/s00270-020-02703-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/31/2020] [Indexed: 12/19/2022]
Abstract
The article is part of the series of articles on radiation protection. You can find further articles in the special section of the CVIR issue. In addition to the risks from fluoroscopic-guided interventional procedures of tissue injuries, recent studies have drawn attention to the risk of stochastic effects. Guidelines exist for preprocedural planning and radiation management during the procedure. The concept of a substantial radiation dose level (SRDL) is helpful for patient follow-up for tissue injury. The uncommon nature of tissue injuries requires the interventionalist to be responsible for follow-up of patients who receive substantial radiation doses. Dose management systems for recognizing and avoiding higher patient exposures have been introduced. The European Directive provides a legal framework and requirements for equipment, training, dose monitoring, recording and optimization that are helpful in radiation risk management.
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[Use of radiopharmaceuticals in pediatrics: Specificities and recommandations of SoFRa (Société française de radiopharmacie)]. ANNALES PHARMACEUTIQUES FRANÇAISES 2020; 79:230-243. [PMID: 33159849 DOI: 10.1016/j.pharma.2020.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/22/2020] [Accepted: 10/13/2020] [Indexed: 11/20/2022]
Abstract
Radiopharmaceuticals are commonly used in children in nuclear medicine. Because of physiological differences in growing children and their radiosensitivity, precautions must be taken throughout the medication use process. The aim of this work is to propose recommendations, under the aegis of the Société française de radiopharmacie (SoFRa), for each subsystem of the process, in order to ensure the safety of pediatric patients. Furthermore, an analysis of two surveys on diagnostic radiopharmaceuticals dosage used in different nuclear medicine departments in France is detailed. Recommendations for therapeutic radiopharmaceuticals are also provided. Specificities of the preparation for pediatric patients are discussed through the example of the radiopharmaceuticals for lung perfusion scintigraphy. The preparation of individual dose and administration are also described. In nuclear medicine, radiopharmacist's expertise is essential for patient safety. A multidisciplinary approach is necessary to secure pediatric radiopharmaceutical use process.
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Nikeghbal K, Zamanian Z, Shahidi S, Spagnuolo G, Soltani P. Designing and Fabricating Nano-structured and Micro-structured Radiation Shields for Protection against CBCT Exposure. MATERIALS 2020; 13:ma13194371. [PMID: 33008078 PMCID: PMC7579218 DOI: 10.3390/ma13194371] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/21/2020] [Accepted: 09/28/2020] [Indexed: 12/14/2022]
Abstract
Researchers have always been interested in finding new and effective materials for protection against radiation. This experimental study aimed to design and fabricate new types of nano-material and micro-material based shields against the ionizing effect of cone beam computed tomography (CBCT) X-rays. To fabricate a flexible prototype, we added dioctyl phthalate (DOP) oil to emulsion polyvinyl chloride (PVC) powder. The paste was mixed and dispersed. Then, nano- and micro-powders of WO3 and Bi2O3 were added to the paste, with the weight ratio of 20% PVC, 20% DOP, and 60% nano- and micro-metals. Using an ultrasonic mixer, the polymer matrix and metals were mixed and a paste with a thick texture was developed. The resultant paste was poured into glass molds and the molds were then heated in an oven. After cooling, the resultant sheets were selected for further experiments. A CBCT unit and dosimeter were used to evaluate the characterization and X-ray shielding properties of the fabricated prototypes. The half-value layers (HVL) for nano-WO3, micro-WO3, nano-Bi2O3, and micro-Bi2O3 were 0.0390, 0.0524, 0.0351, and 0.0374 cm, respectively. In addition, the linear attenuation coefficient (µ) for these materials were 17.77, 13.20, 19.71, and 18.5 cm−1, respectively. The findings indicate that nano-structured samples are more effective in the attenuation of X-ray energy. The nano-structured WO3 prototype was nearly 34% more efficient in attenuating radiation compared to the micro-structured WO3 prototype. This difference in nano- and micro-structured Bi2O3 prototypes was 6.5%.
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Affiliation(s)
- Kiana Nikeghbal
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medical Sciences, Shiraz 71937, Iran;
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Shahrekord University of Medical Sciences, Shahrekord 88168, Iran
| | - Zahra Zamanian
- Department of Occupational Health Engineering, School of Health, Shiraz University of Medical Sciences, Shiraz 71937, Iran
- Correspondence: (Z.Z.); (G.S.)
| | - Shoaleh Shahidi
- Biomaterial Research Center, Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medical Sciences, Shiraz 71937, Iran;
| | - Gianrico Spagnuolo
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples “Federico II”, 80125 Naples, Italy
- Correspondence: (Z.Z.); (G.S.)
| | - Parisa Soltani
- Department of Oral and Maxillofacial Radiology, Dental Implants Research Center, Dental Research Institute, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746, Iran;
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12
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Gaêta-Araujo H, Alzoubi T, Vasconcelos KDF, Orhan K, Pauwels R, Casselman JW, Jacobs R. Cone beam computed tomography in dentomaxillofacial radiology: a two-decade overview. Dentomaxillofac Radiol 2020; 49:20200145. [PMID: 32501720 DOI: 10.1259/dmfr.20200145] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
OBJECTIVES The aim of this study was to evaluate and summarise features of currently and formerly available cone beam CT (CBCT) devices from 1996 to 2019. Additionally, a recommendation for standardised reporting of CBCT characteristics was provided. METHODS AND MATERIALS Information about the features of all available CBCT devices was obtained from the manufacturers' available data. Moreover, site visits to newly developed CBCT machines' manufacturers were performed in order to obtain relevant information. RESULTS A total of 279 CBCT models from 47 manufacturers located in 12 countries (Brazil, China, Denmark, Finland, France, Germany, Italy, Japan, Republic of Korea, Slovakia, Thailand, and USA) could be listed. Overall, wide variations in CBCT features and technical specifications were identified. CONCLUSIONS CBCT in dentomaxillofacial radiology is a generic term applicable to a broad range of CBCT machines and features. Experimental outcomes and literature statements regarding radiation doses, imaging performance and diagnostic applicability of dental CBCT cannot be simply transferred from one CBCT model to another considering a wide variation in technical characteristics and clinical diagnostic performance. The information tabulated in the present study will be later provided on the International Association of DentoMaxilloFacial Radiology website (www.iadmfr.one).
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Affiliation(s)
- Hugo Gaêta-Araujo
- OMFS IMPATH Research Group, Department of Imaging & Pathology, Faculty of Medicine, University of Leuven and Oral & Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium.,Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil
| | - Tamara Alzoubi
- OMFS IMPATH Research Group, Department of Imaging & Pathology, Faculty of Medicine, University of Leuven and Oral & Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Karla de Faria Vasconcelos
- OMFS IMPATH Research Group, Department of Imaging & Pathology, Faculty of Medicine, University of Leuven and Oral & Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Kaan Orhan
- OMFS IMPATH Research Group, Department of Imaging & Pathology, Faculty of Medicine, University of Leuven and Oral & Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium.,Department of DentoMaxillofacial Radiology, Ankara University, Faculty of Dentistry, Ankara, Turkey
| | - Ruben Pauwels
- Medical Physics & Quality Assessment Department of Imaging & Pathology, Faculty of Medicine, Catholic University of Leuven, Leuven, Belgium.,Aarhus Institute of Advanced Studies, Aarhus University, Aarhus, Denmark
| | | | - Reinhilde Jacobs
- OMFS IMPATH Research Group, Department of Imaging & Pathology, Faculty of Medicine, University of Leuven and Oral & Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium.,Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
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Gao Y, Mahmood U, Liu T, Quinn B, Gollub MJ, Xu XG, Dauer LT. Patient-Specific Organ and Effective Dose Estimates in Adult Oncologic CT. AJR Am J Roentgenol 2020; 214:738-746. [PMID: 31414882 PMCID: PMC7393764 DOI: 10.2214/ajr.19.21197] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE. Patient-specific organ and effective dose provides essential information for CT protocol optimization. However, such information is not readily available in the scan records. The purpose of this study was to develop a method to obtain accurate examination- and patient-specific organ and effective dose estimates by use of available scan data and patient body size information for a large cohort of patients. MATERIALS AND METHODS. The data were randomly collected for 1200 patients who underwent CT in a 2-year period. Physical characteristics of the patients and CT technique were processed as inputs for the dose estimator. Organ and effective doses were estimated by use of the inputs and computational human phantoms matched to patients on the basis of sex and effective diameter. Size-based ratios were applied to correct for patient-phantom body size differences. RESULTS. Patients received a mean of 59.9 mGy to the lens of the eye per brain scan, 10.1 mGy to the thyroid per chest scan, 17.5 mGy to the liver per abdomen and pelvis scan, and 19.0 mGy to the liver per body scan. A factor of 2 difference in dose estimates was observed between patients of various habitus. CONCLUSION. Examination- and patient-specific organ and effective doses were estimated for 1200 adult oncology patients undergoing CT. The dose conversion factors calculated facilitate rapid organ and effective dose estimation in clinics. Compared with nonspecific dose estimation methods, patient dose estimations with data specific to the patient and examination can differ by a factor of 2.
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Affiliation(s)
- Yiming Gao
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Usman Mahmood
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Tianyu Liu
- Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Brian Quinn
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Marc J. Gollub
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - X. George Xu
- Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Lawrence T. Dauer
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
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Bletsa A, Bessonova MV, Iden O. Using Cone-beam CT in Diagnosis and Management of Severe Dilaceration Following Trauma in Primary Teeth: A Case Report. Int J Clin Pediatr Dent 2020; 13:S110-S114. [PMID: 34434025 PMCID: PMC8359877 DOI: 10.5005/jp-journals-10005-1868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
AIM This case report illustrates the multidisciplinary treatment of a 12-year-old boy with esthetic challenges and endodontic problems in his maxillary incisors after severe dental injury at the age of 2½ years. BACKGROUND The close anatomic relationship of the primary tooth to the permanent tooth germ explains why traumatic dental injuries in primary dentition may affect the development of permanent teeth especially in the maxillary anterior region. Developmental defects of enamel (DDE) as well as crown/root dilacerations are often seen after displacement injuries such as intrusion or avulsion occurring at lower age. CASE DESCRIPTION A 12-year-old boy with severe discoloration and enamel hypoplasia of his maxillary incisors was treated with composite restorations. History of avulsion injury of teeth 51 and 61 at the age of 2½ years explained the DDE, the severe dilaceration, and delayed tooth eruption of tooth 21. Use of cone-beam computed tomography (CBCT) was decisive in diagnosis and treatment planning of esthetic concerns and endodontic complications. CONCLUSION Trauma to primary teeth taking place at early childhood may have severe consequences on permanent successors. CLINICAL SIGNIFICANCE Severe morphological variations in permanent incisors caused by dental injuries in the predecessor teeth require monitoring and multidisciplinary approach. Advanced three-dimensional radiographic imaging is useful in identification and treatment planning of such cases. HOW TO CITE THIS ARTICLE Bletsa A, Bessonova MV, Iden O. Using Cone-beam CT in Diagnosis and Management of Severe Dilaceration Following Trauma in Primary Teeth: A Case Report. Int J Clin Pediatr Dent 2020;13(S-1):S110-S114.
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Affiliation(s)
- Athanasia Bletsa
- Oral Health Centre of Expertise in Western Norway, Vestland, Bergen, Norway
| | - Maria V Bessonova
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Ole Iden
- Oral Health Centre of Expertise in Western Norway, Vestland, Bergen, Norway
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Beganović A, Ciraj-Bjelac O, Dyakov I, Gershan V, Kralik I, Milatović A, Šalát D, Stepanyan K, Vladimirov A, Vassileva J. IAEA survey of dental cone beam computed tomography practice and related patient exposure in nine Central and Eastern European countries. Dentomaxillofac Radiol 2019; 48:20190157. [PMID: 31530009 DOI: 10.1259/dmfr.20190157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES Cone beam CT (CBCT) in dentistry and maxillofacial surgery is a widely used imaging method for the assessment of various maxillofacial and dental pathological conditions. The objective of this study was to summarize the results of a multinational retrospective-prospective study that focused on patient exposure in this modality. METHODS The study included 27 CBCT units and 325 adult and paediatric patients, in total. Data on patients, clinical indications, technical parameters of exposure, patient dose indicator, or, alternatively, dose to phantom were collected. The dose indicator used was air kerma-area product, PKA. RESULTS In most scanners operators are offered with a variety of options regarding technical parameters, especially the field of view size. The median and the third quartile value of PKA for adult patients in 14 different facilities were 820 mGy cm² and 1000 mGy cm² (interquartile range = 1058 mGy cm²), and 653 mGy cm² and 740 mGy cm² (interquartile range = 1179 mGy cm²) for children, as reported by four different institutions. Phantom dose data were reported from 15 institutions, and median PKA ranged from 125 mGy cm² to 1951 mGy cm². Median PKA values varied by more than a 10-fold between institutions, mainly due to differences in imaging protocol used, in particular field of view and tube current-exposure time product. CONCLUSIONS The results emphasize the need for a cautious approach to using dental CBCT. Imaging only when the clinical indications are clear, accompanied with the appropriate radiographic techniques and the optimum imaging protocol, will help reduce radiation dose to patients.
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Affiliation(s)
- Adnan Beganović
- Clinical Centre of Sarajevo University, Sarajevo, Bosnia and Herzegovina
| | | | | | - Vesna Gershan
- Ss. Cyril and Methodius University, Skopje, North Macedonia
| | | | | | - Dušan Šalát
- University of St. Cyril and Methodius, Trnava, Slovakia
| | - Karapet Stepanyan
- Department of Radiation Safety, Ministry of Health, Yerevan, Armenia
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Bianchi J, Gonçalves JR, Ruellas ACDO, Vimort JB, Yatabe M, Paniagua B, Hernandez P, Benavides E, Soki FN, Cevidanes LHS. Software comparison to analyze bone radiomics from high resolution CBCT scans of mandibular condyles. Dentomaxillofac Radiol 2019; 48:20190049. [PMID: 31075043 PMCID: PMC6747438 DOI: 10.1259/dmfr.20190049] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/25/2019] [Accepted: 04/27/2019] [Indexed: 01/09/2023] Open
Abstract
OBJECTIVES Radiomics refers to the extraction and analysis of advanced quantitative imaging from medical images to diagnose and/or predict diseases. In the dentistry field, the bone data from mandibular condyles could be computationally analyzed using the voxel information provided by high-resolution CBCT scans to increase the diagnostic power of temporomandibular joint (TMJ) conditions. However, such quantitative information demands innovative computational software, algorithm implementation, and validation. Our study's aim was to compare a newly developed BoneTexture application to two-consolidated software with previous applications in the medical field, Ibex and BoneJ, to extract bone morphometric and textural features from mandibular condyles. METHODS We used an imaging database of HR-CBCT TMJs scans with an isotropic voxel size of 0.08 mm3 . A single group with 66 distinct mandibular condyles composed the final sample. We calculated 18 variables for bone textural features and 5 for bone morphometric measurements using the Ibex, BoneJ and BoneTexture applications. Spearman correlation and Bland-Altman plot analyses were done to compare the agreement among software. RESULTS The results showed a high Spearman correlation among the software applications ( r = 0.7-1), with statistical significance for all variables, except Grey Level Non-Uniformity and Short Run Emphasis. The Bland-Altman vertical axis showed, in general, good agreement between the software applications and the horizontal axis showed a narrow average distribution for Correlation, Long Run Emphasis and Long Run High Grey Level Emphasis. CONCLUSIONS Our data showed consistency among the three applications to analyze bone radiomics in high-resolution CBCT. Further studies are necessary to evaluate the applicability of those variables as new bone imaging biomarkers to diagnose bone diseases affecting TMJs.
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Affiliation(s)
| | - João Roberto Gonçalves
- Department of Pediatric Dentistry, São Paulo State University (Unesp), School of Dentistry, Araraquara, SP, Brazil
| | | | | | - Marília Yatabe
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | | | | | - Erika Benavides
- Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Fabiana Naomi Soki
- Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
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Suzuki S, Katada Y, Takayanagi T, Sugawara H, Ishikawa T, Yamamoto Y, Wada H. Evaluation of three-dimensional iterative image reconstruction in C-arm-based interventional cone-beam CT: A phantom study in comparison with customary reconstruction technique. Medicine (Baltimore) 2019; 98:e14947. [PMID: 30921193 PMCID: PMC6456140 DOI: 10.1097/md.0000000000014947] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
We compared images obtained using a three-dimensional iterative image reconstruction (3D-IIR) algorithm for C-arm-based interventional cone-beam computed tomography (CBCT) with that using the customary reconstruction technique to quantify the effect of reconstruction techniques on image quality.We scanned 2 phantoms using an angiography unit with digital flat-panel system-an elliptical cylinder acrylic phantom to evaluate spatial resolution and a Catphan phantom to evaluate CT number linearity, image noise, and low-contrast resolution. Three-dimensional imaging was calculated using Feldkamp algorithms, and additional image sets were reconstructed using 3D-IIR at 5 settings (Sharp, Default, Soft+, Soft++, Soft+++). We evaluated quality of images obtained using the 6 reconstruction techniques and analyzed variance to test values of the 10% value of each MTF, mean CT number, and contrast-to-noise ratio (CNR), with P < .05 considered statistically significant.Modulation transfer function curves and CT number linearity among images obtained using the customary technique and the 5 3D-IIR techniques showed excellent agreement. Noise power spectrum curves demonstrated uniform noise reduction across the spatial frequency in the iterative reconstruction, and CNR obtained using all but the Sharp 3D-IIR technique was significantly better than that using the customary reconstruction technique (Sharp, P = .1957; Default, P = .0042; others, P < .0001). Use of 3D-IIR, especially the Soft++ and Soft+++ settings, improved visualization of low-contrast targets.Use of a 3D-IIR can significantly improve image noise and low-contrast resolution while maintaining spatial resolution in C-arm-based interventional CBCT, yielding higher quality images that may increase safety and efficacy in interventional radiology.
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Affiliation(s)
- Shigeru Suzuki
- Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku
| | - Yoshiaki Katada
- Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku
| | - Tomoko Takayanagi
- Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku
- Department of Radiology, Graduate School of Medicine, University of Tokyo, Bunkyo-ku
| | - Haruto Sugawara
- Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku
- Department of Radiology, Graduate School of Medicine, University of Tokyo, Bunkyo-ku
| | - Takuya Ishikawa
- Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku
| | - Yuzo Yamamoto
- Department of Radiology, Tokyo Women's Medical University Medical Center East, Arakawa-ku
| | - Hiroo Wada
- Department of Public Health, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan
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Baptista M, Di Maria S, Vieira S, Santos J, Pereira J, Pereira M, Vaz P. Dosimetric assessment of the exposure of radiotherapy patients due to cone-beam CT procedures. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2019; 58:21-37. [PMID: 30392077 DOI: 10.1007/s00411-018-0760-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 10/30/2018] [Indexed: 06/08/2023]
Abstract
Cone-beam computed tomography (CBCT) is widely used for pre-treatment verification and patient setup in image-guided radiation therapy (IGRT). CBCT imaging is employed daily and several times per patient, resulting in potentially high cumulative imaging doses to healthy tissues that surround exposed target organs. Computed tomography dose index (CTDI) is the parameter used by CBCT equipment as indication of the radiation output to patients. This study aimed to increase the knowledge on the relation between CBCT organ doses and weighted CTDI (CTDIW) for a thorax scanning protocol. A CBCT system was modelled using the Monte Carlo (MC) radiation transport program MCNPX2.7.0. Simulation results were validated against half-value layer (HVL), axial beam profile, patient skin dose (PSD) and CTDI measurements. For organ dose calculations, a male voxel phantom ("Golem") was implemented with the CBCT scanner computational model. After a successful MC model validation with measurements, a systematic comparison was performed between organ doses (and their distribution) and CTDI dosimetry concepts [CTDIW and cumulative dose quantities f100(150) and [Formula: see text]]. The results obtained show that CBCT organ doses vary between 1.2 ± 0.1 mGy and 3.3 ± 0.2 mGy for organs located within the primary beam. It was also verified that CTDIW allows prediction of absorbed doses to tissues at distances of about 5 cm from the isocentre of the CBCT system, whereas f100(150) allows prediction of organ doses at distances of about 10 cm from the isocentre, independently from its location. This study demonstrates that these dosimetric concepts are suitable methods that easily allow a good approximation of the additional CBCT imaging doses during a typical lung cancer IGRT treatment.
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Affiliation(s)
- Mariana Baptista
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal.
| | - Salvatore Di Maria
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal
| | - Sandra Vieira
- Fundação Champalimaud, Centro Clínico Champalimaud, Avenida de Brasília, 1400-038, Lisbon, Portugal
| | - Joana Santos
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal
- Instituto Politécnico de Coimbra, ESTESC, DIMR, Rua 5 de Outubro, 3046-854, Coimbra, Portugal
| | - Joana Pereira
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal
- Laboratório de Protecção e Segurança Radiológica, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal
| | - Miguel Pereira
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal
- Laboratório de Protecção e Segurança Radiológica, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal
| | - Pedro Vaz
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Campus Tecnológico e Nuclear, Estrada Nacional 10, km 139,7, 2695-066, Bobadela LRS, Portugal
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Mizban L, El-Belihy M, Vaidyanathan M, Brown J. An audit and service evaluation of the use of cone beam computed tomography (CBCT) in a paediatric dentistry department. Dentomaxillofac Radiol 2019; 48:20180393. [PMID: 30707638 DOI: 10.1259/dmfr.20180393] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES CBCT exposes the paediatric patient to a higher X-ray dose and risk than normal dental radiographs. This study has two components: an audit and service evaluation. The audit aims to assess whether the use of CBCT in a Paediatric Dentistry department at a London hospital complies with European guidelines (SEDENTEXCT). The service evaluation aims to explore the influence of CBCT on treatment planning. METHODS Two 6 month audit cycles were completed, where CBCT requests were audited to check whether image justifications comply with SEDENTEXCT. For the service evaluation, a total of 50 patient records were examined for the effect of CBCT on definitive treatment plans. RESULTS The first audit demonstrated 94% compliance with SEDENTEXCT. After instituting staff training in CBCT, compliance improved to 100%. In the service evaluation, 100% of CBCTs were found to provide information that impacted on the clinicians' treatment planning, diagnosis and/or management. Of most significance, 44% of treatment plans were changed because of new information provided by CBCT. CONCLUSIONS There are few studies investigating the use of CBCT in paediatric dentistry and the impact of this investigation. This service evaluation shows that CBCT can play an important role in optimising paediatric patient outcomes. The need for robust staff training in CBCT referrals to prevent over prescription is demonstrated in the audit cycles.
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Affiliation(s)
- Laith Mizban
- 1 Department of Paediatric Dentistry, Faculty of Dentistry, Guy's and St Thomas' Hospitals , London , UK
| | - Mohamed El-Belihy
- 2 Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Oral & Craniofacial Sciences, Guy's and St Thomas' Hospitals , London , UK
| | - Mina Vaidyanathan
- 1 Department of Paediatric Dentistry, Faculty of Dentistry, Guy's and St Thomas' Hospitals , London , UK
| | - Jackie Brown
- 2 Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Oral & Craniofacial Sciences, Guy's and St Thomas' Hospitals , London , UK
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Men K, Dai J. A comprehensive evaluation of angular range and separation on image quality, image registration, and imaging dose for cone beam computed tomography in radiotherapy. Med Dosim 2019; 44:67-73. [DOI: 10.1016/j.meddos.2018.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/16/2018] [Accepted: 02/12/2018] [Indexed: 12/31/2022]
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Mishra I, Karjodkar FR, Sansare K, Dora AC, Tambawala SS, Kapoor R, Sharma SR. Diagnostic Value of Extraoral Periapical Radiograph in Comparison to Intraoral Periapical Radiograph: A Cross-sectional, Institutional Study. Contemp Clin Dent 2018; 9:406-409. [PMID: 30166835 PMCID: PMC6104369 DOI: 10.4103/ccd.ccd_152_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Background: Radiographs form an invaluable adjunct in diagnosis, treatment planning, and postoperative evaluation during patient management in the dental office where intraoral periapical (IOPA) radiographs are the ones most commonly used. However, certain conditions render the placement of film difficult. In such cases, a panoramic radiograph may be taken, but it has the disadvantage of higher radiation exposure and cost. Extraoral periapical (EOPA) technique allows radiographs to be taken on an IOPA film by placing it extraorally. We aimed to evaluate its diagnostic accuracy compared to intraoral bisecting angle technique. Materials and Methods: Forty-five patients were randomly selected. Ninety radiographs were taken; two for each patient. First image was obtained by intraoral bisecting angle technique and second by EOPA technique. A scale was devised for the comparison of radiographs taken by the two techniques. Two experienced oral radiologists rated them based on the scale followed by statistical analysis. Results: Patients reported increased compliance with the EOPA technique. 84.40% of the EOPA radiographs (EOPARs) were diagnostically acceptable; sensitivity and specificity was 84% and 55%, respectively. Conclusion: EOPAR is beneficial in cases where intraoral film placement is difficult, and a radiograph is necessary for patient management, even though it demonstrates comparatively lesser diagnostic accuracy.
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Affiliation(s)
- Isha Mishra
- Department of Oral Medicine and Radiology, Government Dental College and Hospital, Mumbai, Maharashtra, India
| | - Freny R Karjodkar
- Department Oral Medicine and Radiology, Nair Hospital Dental College, Mumbai, Maharashtra, India
| | - Kaustubh Sansare
- Department Oral Medicine and Radiology, Nair Hospital Dental College, Mumbai, Maharashtra, India
| | - Amaresh Chandra Dora
- Department Oral Medicine and Radiology, Nair Hospital Dental College, Mumbai, Maharashtra, India
| | - Shahnaz S Tambawala
- Department Oral Medicine and Radiology, Nair Hospital Dental College, Mumbai, Maharashtra, India
| | - Ruchika Kapoor
- Department Oral Medicine and Radiology, Nair Hospital Dental College, Mumbai, Maharashtra, India
| | - Sneha R Sharma
- Department Oral Medicine and Radiology, Nair Hospital Dental College, Mumbai, Maharashtra, India
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Barba L, Berrocal AL, Hidalgo A. Uses of cone-beam computed tomography in San José, Costa Rica. Imaging Sci Dent 2018; 48:103-109. [PMID: 29963481 PMCID: PMC6015925 DOI: 10.5624/isd.2018.48.2.103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 04/19/2018] [Accepted: 05/02/2018] [Indexed: 11/18/2022] Open
Abstract
Purpose To analyze cone-beam computed tomography (CBCT) use, indications, and exposure parameters in San José, Costa Rica. Materials and Methods A cross-sectional study was performed. All CBCT examinations over a period of 6 months at 2 radiological centers in San José, Costa Rica were evaluated. The examinations were performed with Veraview EPOC X550 and Veraviewepocs 3D R100 equipment. The patients' age and sex, clinical indication for CBCT, region of interest (ROI), repeat examinations, specialty of the referring dentist, field-of-view (FOV), tube voltage (kV), tube current (mA), and radiation dose (µGy) were evaluated. Patients were classified by age as children (≤12 years), adolescents (13–18 years), and adults (≥19 years). Results The mean age of the 526 patients was 49.4 years. The main indications were implant dentistry and dental trauma. The most frequent ROIs were posterior, while anterior ROIs were much less common. The highest percentage of repeat examinations was in children. Fifty-six percent of the referring dentists were specialists. The most commonly used FOV was small. The mean tube voltage and current were 79.8 kV and 7.4 mA for Veraview EPOC X550 and 89.9 kV and 6 mA for Veraviewepocs 3D R100, respectively. The mean doses for children, adolescents, and adults were 6.9 µGy, 8.4 µGy, and 7.8 µGy, respectively. Conclusion Although CBCT was most commonly used in adults for implant dentistry, most repeat examinations were in children, and the highest mean dose was in adolescents. Additional dose optimization efforts should be made by introducing low-dose protocols for children and adolescents.
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Affiliation(s)
- Lucía Barba
- Specialization Program in Oral and Maxillofacial Imaging, Graduate School, Universidad de Talca, Talca, Chile
| | - Ana Luisa Berrocal
- Department of Diagnostic and Surgical Sciences, Faculty of Dentistry, Universidad de Costa Rica, San José, Costa Rica
| | - Alejandro Hidalgo
- Specialization Program in Oral and Maxillofacial Imaging, Graduate School, Universidad de Talca, Talca, Chile
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Irradiation provided by dental radiological procedures in a pediatric population. Eur J Radiol 2018; 103:112-117. [DOI: 10.1016/j.ejrad.2018.04.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 03/06/2018] [Accepted: 04/21/2018] [Indexed: 11/20/2022]
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de las Heras Gala H, Schöfer F, Schöfer H, Sánchez Casanueva R, Zervides C, Mair K, Al-Zoubi Q, Renger B, de las Heras Gala T, Schlattl H. A patient-centric approach to quality control and dosimetry in CT including CBCT. Phys Med 2018; 47:92-102. [DOI: 10.1016/j.ejmp.2018.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 12/08/2017] [Accepted: 02/07/2018] [Indexed: 11/16/2022] Open
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An SY, Lee KM, Lee JS. Korean dentists' perceptions and attitudes regarding radiation safety and protection. Dentomaxillofac Radiol 2018; 47:20170228. [PMID: 29236521 DOI: 10.1259/dmfr.20170228] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES To investigate dentists' perceptions and attitudes regarding radiation safety in dental practices in Korea. METHODS 207 dentists participated in this study. An anonymous survey was conducted regarding the following areas: years of practice, characteristics of the radiography equipment, knowledge of diagnostic reference levels, prescription of dental radiographs, use of radiation protection procedures and participation in the radiation safety program. Data were evaluated according to frequency distribution; the χ test; and Fisher's exact test, which was used to investigate statistical significances (p < 0.05) between those with less than 10 years of experience in practice vs those with 10 years of experience or more. RESULTS Approximately 83% of the dentists who responded to our survey participated in the radiation safety program, but only 58% were satisfied with it. There were statistically significant differences in the installation of X-ray units, learning pathway of diagnostic reference levels, prescription of dental radiography for new adult patients, use of personnel radiation monitoring systems and participation in the radiation safety program between those with less than 10 years of experience in practice vs those with 10 years of experience or more (p < 0.05). CONCLUSIONS Dentists with less than 10 years of experience were less attentive to radiation protection procedures. Therefore, taking both the duration of experience of dentists and the installed X-ray equipment into consideration, continuous and efficient education for both dental workers and patients regarding radiation safety and protection is recommended.
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Affiliation(s)
- Seo-Young An
- 1 Department of Oral and Maxillofacial Radiology, School of Dentistry, Kyungpook National University , Daegu , Republic of Korea
| | - Kyung-Min Lee
- 2 Department of Orthodontics, School of Dentistry, Chonnam National University , Gwangju , Republic of Korea
| | - Jae-Seo Lee
- 3 Department of Oral and Maxillofacial Radiology, School of Dentistry, Dental Science Research Institute, Chonnam National University , Gwangju , Republic of Korea
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de Las Heras Gala H, Torresin A, Dasu A, Rampado O, Delis H, Hernández Girón I, Theodorakou C, Andersson J, Holroyd J, Nilsson M, Edyvean S, Gershan V, Hadid-Beurrier L, Hoog C, Delpon G, Sancho Kolster I, Peterlin P, Garayoa Roca J, Caprile P, Zervides C. Quality control in cone-beam computed tomography (CBCT) EFOMP-ESTRO-IAEA protocol (summary report). Phys Med 2017; 39:67-72. [PMID: 28602688 DOI: 10.1016/j.ejmp.2017.05.069] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 05/24/2017] [Indexed: 10/19/2022] Open
Abstract
The aim of the guideline presented in this article is to unify the test parameters for image quality evaluation and radiation output in all types of cone-beam computed tomography (CBCT) systems. The applications of CBCT spread over dental and interventional radiology, guided surgery and radiotherapy. The chosen tests provide the means to objectively evaluate the performance and monitor the constancy of the imaging chain. Experience from all involved associations has been collected to achieve a consensus that is rigorous and helpful for the practice. The guideline recommends to assess image quality in terms of uniformity, geometrical precision, voxel density values (or Hounsfield units where available), noise, low contrast resolution and spatial resolution measurements. These tests usually require the use of a phantom and evaluation software. Radiation output can be determined with a kerma-area product meter attached to the tube case. Alternatively, a solid state dosimeter attached to the flat panel and a simple geometric relationship can be used to calculate the dose to the isocentre. Summary tables including action levels and recommended frequencies for each test, as well as relevant references, are provided. If the radiation output or image quality deviates from expected values, or exceeds documented action levels for a given system, a more in depth system analysis (using conventional tests) and corrective maintenance work may be required.
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Affiliation(s)
| | - Alberto Torresin
- Education and Training Chairperson of EFOMP, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy
| | - Alexandru Dasu
- The Skandion Clinic, Uppsala, Sweden; Linköping University, Linköping, Sweden
| | | | - Harry Delis
- International Atomic Energy Agency, Vienna, Austria
| | | | | | - Jonas Andersson
- Department of Radiation Sciences, Radiation Physics, University of Umeå, Umeå, Sweden
| | | | | | - Sue Edyvean
- Public Health England (PHE), Chilton, Didcot, Oxfordshire, UK
| | - Vesna Gershan
- Faculty of Natural Sciences and Mathematics, Skopje, Macedonia
| | | | | | | | | | | | | | - Paola Caprile
- Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Costas Zervides
- Zervides Radiation Protection Services, Limassol, Cyprus; University of Nicosia, Medical School, Nicosia, Cyprus
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Tonkopi E, Ross AA. ASSESSMENT OF EFFECTIVE DOSE FROM CONE BEAM CT IMAGING IN SPECT/CT EXAMINATION IN COMPARISON WITH OTHER MODALITIES. RADIATION PROTECTION DOSIMETRY 2016; 172:438-442. [PMID: 26769909 DOI: 10.1093/rpd/ncv534] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 11/20/2015] [Accepted: 11/25/2015] [Indexed: 06/05/2023]
Abstract
The aim of this study was to assess radiation dose from the cone beam computed tomography (CBCT) component of single photon emission tomography/computed tomography (SPECT/CT) examinations and to compare it with the radiopharmaceutical related dose as well as dose from multidetector computed tomography (MDCT). Effective dose (ED) from computed tomography (CT) was estimated using dose-length product values and anatomy-specific conversion factors. The contribution from the SPECT component was evaluated using ED per unit administered activity for the radiopharmaceuticals listed in the International Commission on Radiological Protection Publications 80 and 106. With the exception of cardiac studies (0.11 mSv), the CBCT dose (3.96-6.04 mSv) was similar to that from the radiopharmaceutical accounting for 29-56 % of the total ED from the examination. In comparison with MDCT examinations, the CBCT dose was 48 and 42 % lower for abdomen/pelvis and chest/abdomen/pelvis scans, respectively, while in the chest the CBCT scan resulted in higher dose (23 %). Radiation dose from the CT component should be taken into consideration when evaluating total SPECT/CT patient dose.
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Affiliation(s)
- Elena Tonkopi
- Department of Diagnostic Radiology, Dalhousie University, 1276 South Park Street, Halifax, NS B3H2Y9, Canada
- Department of Diagnostic Imaging, Queen Elizabeth II Health Sciences Centre, 1276 South Park Street, Halifax, NS B3H2Y9, Canada
| | - Andrew A Ross
- Department of Diagnostic Radiology, Dalhousie University, 1276 South Park Street, Halifax, NS B3H2Y9, Canada
- Department of Diagnostic Imaging, Queen Elizabeth II Health Sciences Centre, 1276 South Park Street, Halifax, NS B3H2Y9, Canada
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Ariyaratne H, Chesham H, Pettingell J, Alonzi R. Image-guided radiotherapy for prostate cancer with cone beam CT: dosimetric effects of imaging frequency and PTV margin. Radiother Oncol 2016; 121:103-108. [PMID: 27576431 DOI: 10.1016/j.radonc.2016.07.018] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 06/11/2016] [Accepted: 07/03/2016] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND PURPOSE This study assesses the effect of frequency of cone beam CT (CBCT) verification imaging on dose-volume parameters during image-guided radiotherapy (IGRT) for prostate cancer. It also investigates the dosimetric impact of reducing the planning target volume (PTV) margin, when daily imaging is used. MATERIAL AND METHODS 844 CBCT images from 20 patients undergoing radical prostate radiotherapy were included. Patients received a dose of 74Gy in 37 fractions using 7-field intensity-modulated radiotherapy (IMRT). Clinical target volume (CTV) and organs at risk were contoured manually on each slice of every CBCT image. A daily online CBCT verification schedule was compared with a protocol of verification on days 1-3 followed by weekly online imaging. PTV margins of 3mm, 5mm, and 7mm were compared for the daily imaging protocol. RESULTS 90% of patients had improved target coverage with daily online in comparison to weekly online imaging. A median of 37 fractions per treatment course achieved CTV coverage with daily imaging compared to 34 fractions with a weekly online protocol. 80% of patients had a reduction in rectal dose with the daily protocol. PTV margin reduction to 5mm with adequate target coverage was feasible with daily imaging. CONCLUSIONS Daily online CBCT verification improves CTV coverage and reduces rectal dose during IGRT for prostate cancer. Tighter PTV margins could be considered with daily CBCT use.
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