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Velonis M, Papanastasiou E, Hatziioannou K, Siountas A, Kamperis E, Papavasileiou P, Koukourakis MI, Seimenis I. Dose optimization of 2D X-ray image acquisition protocols in image-guided radiotherapy. Phys Med 2023; 115:103161. [PMID: 37847953 DOI: 10.1016/j.ejmp.2023.103161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 09/06/2023] [Accepted: 10/06/2023] [Indexed: 10/19/2023] Open
Abstract
PURPOSE In contemporary radiotherapy, patient positioning accuracy relies on kV imaging. This study aims at optimizing planar kV image acquisition protocols regarding patient dose without degrading image quality. MATERIALS AND METHODS An image quality test-object was placed in-between PMMA plates, suitably arranged to model head or pelvis. Constructed phantoms were imaged using default protocols, the resultant image quality was assessed and the corresponding radiation dose was measured. The process was repeated using numerous kV/mAs combinations to identify those acquisition settings providing images at lower dose than the default protocols but without deterioration in image quality. Default and dose-optimized protocols were then tested on an anthropomorphic phantom and on 51 patients during two successive treatment sessions. Image quality was independently assessed by two readers. Organ and effective doses were estimated using a Monte Carlo simulation software. RESULTS Low-contrast detectability exhibited a stronger dependence on kV/mAs settings, compared to high-contrast resolution. Dose-optimized protocols resulted in significant dose reductions (anteroposterior-head 48.0 %, lateral-head 30.0 %, anteroposterior-pelvis 28.4 %, lateral-pelvis 27.0 %) compared to the default ones, without compromising image quality. Optimized protocols decreased effective doses by 54 % and 29.6 % in head and pelvic acquisitions, respectively. Regarding image quality, anthropomorphic and patient images acquired using the dose-optimized protocols were subjectively evaluated equivalent to those obtained with the corresponding default settings, indicating that the proposed protocols may be routinely used. CONCLUSIONS Given the potentially large number of radiotherapy fractions and the pertinent image acquisitions, dose-optimized protocols could significantly reduce patient dose associated with planar imaging without compromising positioning accuracy.
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Affiliation(s)
- Marios Velonis
- Department of Medicine, Faculty of Health Sciences, Democritus University of Thrace, Greece; Department of Medical Physics, Papageorgiou General Hospital, Thessaloniki, Greece.
| | - Emmanouil Papanastasiou
- Medical Physics & Digital Innovation Laboratory, Medical School, Aristotle University of Thessaloniki, Greece
| | | | - Anastasios Siountas
- Medical Physics & Digital Innovation Laboratory, Medical School, Aristotle University of Thessaloniki, Greece
| | - Efstathios Kamperis
- Department of Radiotherapy, Papageorgiou General Hospital, Thessaloniki, Greece
| | - Periklis Papavasileiou
- Department of Biomedical Sciences, School of Health Sciences, University of West Attica, Greece
| | - Michael I Koukourakis
- Department of Medicine, Faculty of Health Sciences, Democritus University of Thrace, Greece
| | - Ioannis Seimenis
- Medical Physics Laboratory, School of Medicine, National and Kapodistrian University of Athens, Greece
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Siraj M, Dalah EZ, Okasha MH, Abdel Kader GI, Mohamed Said MS, Kalanter RA, Razack HA, Mohamad Ahmad AN, Albastaki AA. Potentials of additional copper filtration on radiation dose and image quality for adults underwent digital chest X-ray imaging in Dubai Health Authority - UAE. Radiography (Lond) 2023; 29:552-556. [PMID: 36958232 DOI: 10.1016/j.radi.2023.03.005] [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: 12/30/2022] [Revised: 03/07/2023] [Accepted: 03/08/2023] [Indexed: 03/25/2023]
Abstract
OBJECTIVE To explore the potentials of adding copper (Cu) filter on image quality and patient dose of adult patients underwent chest X-ray examination METHODS: Patients were divided into four groups. Group 1, patients were exposed with no added Cu filter (standard or control), group 2 a 0.1 mm Cu filter was added, group 3 acquired with 0.2 mm Cu filter and group 4 performed with 0.3 mm Cu filter. Exposure index (EI), entrance surface dose (ESD) and dose area product (DAP) were recorded from the modality and retrospectively analyzed. The visual grading analysis score (VGAS) was used to evaluate image quality. Mann-Whitney T-Test and one-way ordinary ANOVA Test were used to evaluate statistical differences including gender-based findings. RESULTS EI, ESD and DAP data for a total of 784 patients (422 male and 362 female) that underwent indirect digital chest radiography exam were collected. Image quality was maintained when adding 0.1 mm Cu filter achieved with ∼19% DAP reduction. Female showed a significant DAP reduction comparing to male registered in the same group. CONCLUSIONS Reducing dose when using indirect digital chest radiography is possible with no trade-off on image quality. No loss of image quality was reported, images were broadly comparable. IMPLICATIONS FOR PRACTICE This study highlights the importance of utilizing the additional copper filter in digital chest radiography.
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Affiliation(s)
- M Siraj
- PHC-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
| | - E Z Dalah
- HQ-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates; College of Medicine, Mohammed Bin Rashid University, Dubai, United Arab Emirates.
| | - M H Okasha
- PHC-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
| | - G I Abdel Kader
- PHC-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
| | - M S Mohamed Said
- PHC-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
| | - R A Kalanter
- HQ-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
| | - H A Razack
- PHC-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
| | - A N Mohamad Ahmad
- PHC-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
| | - A A Albastaki
- PHC-Diagnostic Imaging Department, DAHC, Dubai, United Arab Emirates.
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Optimization of Image Quality and Organ Absorbed Dose for Pediatric Chest X-Ray Examination: In-House Developed Chest Phantom Study. Radiol Res Pract 2022; 2022:3482458. [PMID: 35469151 PMCID: PMC9034961 DOI: 10.1155/2022/3482458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/26/2022] [Accepted: 03/28/2022] [Indexed: 11/17/2022] Open
Abstract
Purpose This study aimed to identify proper exposure techniques to maintain optimal diagnostic image quality with minimum radiation dose for anteroposterior chest X-ray projection in pediatric patients. Methods Briefly, an in-house developed pediatric chest phantom was constructed. Next, nanodot OSLDs were used for organ absorbed dose measurement and placed in the lung area, and the phantom was exposed to various exposure techniques (ranging from 50 to 70 kVp with 1.6, 2, and 2.5 mAs). After that, the phantom was used to assess image quality parameters, including SNR and CNR. Two radiologists assessed the subjective image quality using a visual grading analysis (VGA) technique. Finally, the figure of merit (FOM) was analyzed. Results The developed phantom was constructed successfully and could be useful for dose measurement and image quality assessment. The absorbed dose varied from 0.009 to 0.031 mGy for the range of exposure techniques used. SNR and CNR showed a gradually increasing trend, while kVp and mAs values were increased. The highest kVp (70 kVp) produced the highest SNR and CNR, exhibiting a significant difference compared with 50 and 60 kVp (P < 0.05). The overall VGA score was 3.2 ± 0.3, and the low kVp technique demonstrated better image quality compared with the reference image. Conclusion The optimized exposure technique was identified as 60 kV and 2.5 mAs, indicating the highest FOM score. This work revealed practicable techniques that could be implemented into clinical practice for performing pediatric chest radiography.
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Kolck J, Ziegeler K, Walter-Rittel T, Hermann KGA, Hamm B, Beck A. Clinical utility of postprocessed low-dose radiographs in skeletal imaging. Br J Radiol 2022; 95:20210881. [PMID: 34919419 PMCID: PMC8822553 DOI: 10.1259/bjr.20210881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 11/29/2021] [Accepted: 12/07/2021] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES Radiography remains the mainstay of diagnostic and follow-up imaging. In view of the risks and the increasing use of ionizing radiation, dose reduction is a key issue for research and development. The introduction of digital radiography and the associated access to image postprocessing have opened up new opportunities to minimize the radiation dosage. These advances are contingent upon quality controls to ensure adequate image detail and maintenance of diagnostic confidence. The purpose of this study was to investigate the clinical applicability of postprocessed low-dose images in skeletal radiography. METHODS In our study setting, the median radiation dose for full dose X-rays was 9.61 dGy*cm2 for pelvis, 1.20 dGy*cm2 for shoulder and 18.64 dGy*cm2 for lumbar spine exams. Based on these values, we obtained 200 radiographs for each anatomic region in four consecutive steps, gradually reducing the dose to 84%, 71%, 60% and 50% of the baseline using an automatic exposure control (AEC). 549 patients were enrolled for a total of 600 images. All X-rays were postprocessed with a spatial noise reduction algorithm. Two radiologists assessed the diagnostic value of the radiographs by rating the visualization of anatomical landmarks and image elements on a five-point Likert scale. A mean-sum score was calculated by averaging the two reader's total scores. Given the non-parametric distribution, we used the Mann-Whitney U test to evaluate the scores. RESULTS Median dosage at full dose accounted for 38.4%, 48 and 53.2% of the German reference dose area product for shoulder, pelvis and lumbar spine, respectively. The applied radiation was incrementally reduced to 21.5%, 18.4% and 18.7% of the respective reference value for shoulder, pelvis and lumbar spine. Throughout the study, we observed an estimable tendency of superior quality at higher dosage in overall image quality. Statistically significant differences in image quality were restricted to the 50% dose groups in shoulder and lumbar spine images. Regardless of the applied dosage, 598 out of 600 images were of sufficient diagnostic value. CONCLUSION In digital radiography image postprocessing allows for extensive reduction of radiation dosage. Despite a trend of superior image detail at higher dose levels, overall quality and, more importantly, diagnostic utility of low-dose images was not significantly affected. Therefore, our results not only confirm the clinical utility of postprocessed low-dose radiographs, but also suggest a widespread deployment of this advanced technology to ensure further dose limitations in clinical practice. ADVANCES IN KNOWLEDGE The diagnostic image quality of postprocessed skeletal radiographs is not significantly impaired even after extensive dose reduction by up to 20% of the reference value.
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Affiliation(s)
- Johannes Kolck
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Katharina Ziegeler
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Thula Walter-Rittel
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Bernd Hamm
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Alexander Beck
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
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Xu H, Huang K, Liu B, Cai J, Zheng H, Zheng H, Yang Q, Yao C. Influence of the use of various imaging units and projections on the radiation dose received by children during chest digital radiography. PLoS One 2021; 16:e0255749. [PMID: 34352022 PMCID: PMC8341633 DOI: 10.1371/journal.pone.0255749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/22/2021] [Indexed: 11/18/2022] Open
Abstract
Objective To investigate the impact of the use of different imaging units and projections on radiation dose and image quality during chest digital radiography (DR) in 3- and 4-year-old children. Methods Two hundred forty 3- and 4-year-old participants requiring chest DR were included; they were divided into three groups: supine anterior-posterior projection (APP), standing APP and standing posterior-anterior projection (PAP). Each group included 40 participants who were evaluated using the same imaging unit. The dose area product (DAP) and the entrance surface dose (ESD) were recorded after each exposure. The visual grading analysis score (VGAS) was used to evaluate image quality, and the longitudinal distance (LD) from the apex of the right lung to the apex of the right diaphragm was used to evaluate the inspiration extent. Results DAP and ESD were significantly lower in the standing PAP and APP groups than in the supine APP group (P<0.05), but LD was significantly higher in the standing PAP and APP groups than in the supine APP group (P<0.05). Additionally, the pulmonary field area was significantly higher for the standing PAP group than for the standing and supine APP groups (P<0.05). The correlations between ESD, DAP, and VGAS were positive (P<0.001), showing that larger ESD and DAP correspond to higher VGAS. The correlations between ESD, DAP, and body mass index (BMI) were also positive (P<0.05), indicating that higher BMI corresponds to larger ESD and DAP. Finally, no differences in DAP, ESD, VGAS, LD, pulmonary field area, or BMI were noted between males and females (P>0.05). Conclusion The radiation dose to superficial organs may be lower with standing PAP than with standing APP during chest DR. Standing PAP should be selected for chest DR in 3- and 4-year-old children, as it may decrease the required radiation dose.
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Affiliation(s)
- Hongrong Xu
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China
- National Clinical Research Center for Child Health and Disorders, Chongqing, China
- Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Kaiping Huang
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China
- National Clinical Research Center for Child Health and Disorders, Chongqing, China
- Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Bo Liu
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China
- National Clinical Research Center for Child Health and Disorders, Chongqing, China
- Chongqing Key Laboratory of Pediatrics, Chongqing, China
- * E-mail:
| | - Jinhua Cai
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China
- National Clinical Research Center for Child Health and Disorders, Chongqing, China
- Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Huan Zheng
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Helin Zheng
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Qiurui Yang
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Changhong Yao
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
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Deevband MR, Rahmani F, Ebrahimi Bardar M, Ghorbani M. Optimization of dose and image quality in pediatrics chest digital radiography. J Med Imaging Radiat Sci 2021; 52:443-449. [PMID: 34052183 DOI: 10.1016/j.jmir.2021.05.005] [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: 11/11/2020] [Revised: 03/20/2021] [Accepted: 05/01/2021] [Indexed: 11/26/2022]
Abstract
INTRODUCTION In this study, pediatric chest digital radiography (DR) is evaluated in response to the high volume of chest DR examinations and high radiosensitivity of children and young adults. The aim of the study is to optimize irradiation parameters in chest DR to have dose as low as reasonably achievable (ALARA) and simultaneously obtain improved or preserved image quality. MATERIALS AND METHODS Homogeneous phantoms in terms of density, dimensions, and composition were constructed to produce equivalent chest phantoms with less than 5% error for the 5-10 and 10-15-year-old age groups. The modulation transfer function (MTF), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured for both the reference and new conditions for the two age groups. RESULTS The results indicate that for the 5-10 year old age group, the optimized technique was 75 kVp and 6.3 mAs, in which the dose reduced 10% and the SNR and CNR increased by 0.4% and 6%, respectively, compared to the reference condition. For the 10-15-year-old age group, the 85 kVp and 5 mAs was close to the optimum condition, in which the dose reduced 37% and the SNR and CNR increased by 16% and 4%, respectively, compared to the reference condition. CONCLUSION The introduced optimized conditions in this study are accompanied by lower dose and higher SNR and CNR; therefore, they can be proposed as guides for optimization in clinical practice for pediatric chest digital radiography.
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Affiliation(s)
- Mohammad Reza Deevband
- Biomedical Engineering and Medical Physics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fereshteh Rahmani
- Biomedical Engineering and Medical Physics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Meisam Ebrahimi Bardar
- Department of Medical Physics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
| | - Mahdi Ghorbani
- Biomedical Engineering and Medical Physics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Peacock NE, Steward AL, Riley PJ. An evaluation of the effect of tube potential on clinical image quality using direct digital detectors for pelvis and lumbar spine radiographs. J Med Radiat Sci 2020; 67:260-268. [PMID: 32495517 PMCID: PMC7753839 DOI: 10.1002/jmrs.403] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 04/16/2020] [Accepted: 04/18/2020] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION High kVp techniques, 15% or 10-kVp rules, are well-known dose reduction methods. Traditionally, the use of high tube potential (i.e. increased kVp) is associated with decreased radiographic contrast and overall image quality. Recent studies suggest contrast and image quality are not heavily reliant on kVp with digital systems. This study aims to assess the effects of the high tube potential technique on clinical radiographic image quality when using digital systems, to validate high kVp as a dose saving technique. METHODS A selection of comparable pelvis and lumbar spine radiographs were collected from the hospital's picture archiving and communication system (PACS), with technical factors recorded. All clinical radiographs were assessed by 5 senior radiographers using a 15-point visual grading analysis (VGA) rubric. RESULTS For 40 AP pelvis radiographs and 40 lateral lumbar spine radiographs, reduction in the dose area product (DAP) with higher kVp is seen. Average pelvis DAP at 75 kVp = 14.06 mGy.cm2 ; 85 kVp = 7.47 mGy.cm2 . Average lumbar spine DAP at 80 kVp = 15.76 mGy.cm2 ; 90 kVp = 14.83 mGy.cm2 . Image quality and contrast scores showed no statistically significant difference between the high and low kVp groups (z = 0.06 and 0.12, respectively). Average pelvis VGA score at 75 kVp = 11.26; 85 kVp = 12.55. Average lumbar spine VGA score at 80 kVp = 9.23; 90 kVp = 10.64. CONCLUSIONS The high tube potential techniques allowed for reduced patient radiation doses whilst showing no degradation of diagnostic image quality in a clinical setting. This study successfully validates the high kVp technique as a useful tool for reducing patient radiation doses whilst maintaining high diagnostic image quality for digital pelvis and lumbar spine radiography.
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Affiliation(s)
- Nicole E Peacock
- Department of Medical ImagingWestern HealthFootscrayVICAustralia
- School of Medicine, Faculty of HealthDeakin UniversityWaurn PondsVICAustralia
| | - Adam L Steward
- Department of Medical ImagingWestern HealthFootscrayVICAustralia
| | - Peter J Riley
- School of Medicine, Faculty of HealthDeakin UniversityWaurn PondsVICAustralia
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Steffensen C, Trypis G, Mander GTW, Munn Z. Optimisation of radiographic acquisition parameters for direct digital radiography: A systematic review. Radiography (Lond) 2020; 27:663-672. [PMID: 32948453 DOI: 10.1016/j.radi.2020.08.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 08/25/2020] [Accepted: 08/28/2020] [Indexed: 11/16/2022]
Abstract
INTRODUCTION The objective of this systematic review was to uncover and synthesise all available literature regarding appropriate acquisition parameters for direct digital radiography. It sought to either confirm current practices as optimal, or to uncover practices that may produce more optimised results. METHODS A comprehensive search of published and unpublished literature was undertaken to find studies that evaluated how adjustment of different acquisition parameters affected subjective image quality and patient radiation dose. Eight hundred and fifty-eight studies were retrieved for title and abstract screening. Eighty-nine studies were retrieved for full-text screening, and 23 were included for review and methodological quality screening. RESULTS Narrative synthesis of the 23 included studies revealed limited evidence to guide any potential change or acceptance of currently accepted best practice. Meta-analysis was unable to be performed for any of the included studies due to high levels of methodological heterogeneity. A key finding of this review was that the goals of optimisation research varied greatly across the included studies. CONCLUSION Significant methodological heterogeneity in the included studies limited the number of clinically relevant findings that would give evidence to an acceptance of, or suggest changes to, currently accepted best practice. Improving consistency in approach across future works of technique optimisation will ensure future systematic reviews will be able to provide strong evidence and meta-analysis will be able to be performed. IMPLICATIONS FOR CLINICAL PRACTICE This review highlights that in the literature, studies of optimisation of radiographic acquisition parameters have varying goals. This methodological heterogeneity limits the applicability of systematic reviews and precludes the use of meta-analysis. The authors recommend that a framework for optimisation research be produced as a priority to help improve homogeneity in future research.
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Affiliation(s)
- C Steffensen
- Philips Australia and New Zealand, North Ryde, Australia; JBI, The University of Adelaide, Adelaide, Australia.
| | - G Trypis
- Department of Medical Imaging, Sunshine Coast University Hospital, Sunshine Coast Hospital and Health Service, Birtinya, Australia
| | - G T W Mander
- Department of Medical Imaging, Toowoomba Hospital, Darling Downs Health, Toowoomba, Australia; JBI, The University of Adelaide, Adelaide, Australia
| | - Z Munn
- JBI, The University of Adelaide, Adelaide, Australia
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Ziegeler K, Siepmann S, Hermann S, Beck A, Lembcke A, Hamm B, Hermann KGA. Application of an advanced noise reduction algorithm for imaging of hands in rheumatic diseases: evaluation of image quality compared to standard-dose images. Rheumatol Int 2020; 40:893-899. [PMID: 32240350 DOI: 10.1007/s00296-020-04560-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/17/2020] [Indexed: 10/24/2022]
Abstract
OBJECTIVES X-ray is the fundamental imaging technique in both diagnosis and follow-up of rheumatic diseases. As patients often require sequential X-rays over many years, dose reduction is of great importance. New advanced noise reduction algorithms allow for a dose reduction of up to 50%. The aim of this study was to evaluate whether quality of low-dose images is non-inferior to standard-dose images and, therefore, application of this technique is possible in the context of imaging of rheumatic diseases. METHODS A total of 298 patients with known or suspected rheumatic disease were enrolled prospectively into this study, separated into three consecutive groups: 80%, 64% and 50% tube charge reduction. All patients received imaging of one hand (laterality randomly assigned) with low-dose technique and imaging of the contralateral hand with standard-dose protocol. Images were evaluated by two independent readers who scored (on a scale of 1-5) the visualization of bony cortex, trabeculae and joint spaces of fingers and wrist separately. Additionally, soft tissue and overall contrast were evaluated on the same scale. RESULTS Overall image quality (expressed by mean sum score out of 40) of the 50% low-dose images was 31.52 (SD 1.94) vs. 31.66 (SD 1.82) for standard images (p = 0.068). Bony contours as well as trabeculae were equally well visualized in both image sets. Median scores for soft tissue visualization was slightly lower for low dose compared to standard images [4 (IQR 3.5-4) vs. 4 (IQR 3.88-4); p = 0.001]. CONCLUSIONS Overall image quality of low-dose images was not inferior to standard-dose images. Therefore, the application of low-dose technology based on advanced noise estimation algorithms in the context of imaging of rheumatic diseases is possible.
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Affiliation(s)
- Katharina Ziegeler
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.
| | - Stefan Siepmann
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Sandra Hermann
- Department of Rheumatology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Alexander Beck
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Alexander Lembcke
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Kay Geert A Hermann
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
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Hayre CM, Bungay H, Jeffery C. How effective are lead-rubber aprons in protecting radiosensitive organs from secondary ionizing radiation? Radiography (Lond) 2020; 26:e264-e269. [PMID: 32303421 DOI: 10.1016/j.radi.2020.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/25/2020] [Accepted: 03/26/2020] [Indexed: 11/17/2022]
Abstract
INTRODUCTION The purpose of this experiment was to explore the direction of scattered secondary ionizing radiation to a patient. A left lateral radiographic examination of the elbow was deemed appropriate due to its close proximity to radiosensitive organs and record dose limiting opportunities upon wearing a lead-rubber apron. METHODS An anthropomorphic phantom and lead-rubber apron (Pb 0.35 mm) was used with a 15 cc ionization chamber (model 10,100 AT TRIAD) to measure scattered radiation to radiosensitive organs. Dose readings were recorded before and after in order to quantify dose reduction. Pearson's correlation, linear regression, t-test and one way analysis of variance (ANOVA) statistics were used to affirm how likely dose limitation was attributed to chance (p < 0.05). RESULTS The lead-rubber apron offered dose reduction to most radiosensitive organs. Notably, ionizing radiation was significantly reduced to the left breast 0.0083 μGy (98%), right breast 0.0000 μGy (99.9%) and spleen 0.0262 μGy (99.9%). No empirical benefit was recorded for testes and ovaries. Interestingly, the thyroid recorded an increase in dose (0.1733 μGy; p = 0.01). This was later mitigated using a thyroid collar but identifies increased stochastic risks if lead-aprons are worn alone. Scattered radiation was also reduced to both eyes, which were not directly covered. CONCLUSION Lead-rubber aprons are generally utilized to limit ionizing radiation, yet this article offers insight whereby increases to ionizing radiation to the thyroid are plausible when wearing a lead-rubber apron alone. Whilst these findings cannot be generalized to other radiographic examinations it provides insight into a potential increase risk of scatter to a radiosensitive organ. IMPLICATIONS FOR PRACTICE This paper has implications because it identifies that lead-rubber has an impact on scattered ionizing radiation to radiosensitive organs for a lateral elbow examination. Further, it identifies the potential for ionizing radiation to be increased to the thyroid upon wearing a lead-rubber apron alone.
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Affiliation(s)
- C M Hayre
- Charles Sturt University, New South Wales, Australia; University of Suffolk, Ipswich, United Kingdom.
| | - H Bungay
- Anglia Ruskin University, Cambridge, United Kingdom.
| | - C Jeffery
- Canterbury Christ Church University, Canterbury, Kent, United Kingdom.
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Al-Murshedi S, Peter Hogg, England A. Neonatal chest radiography: Influence of standard clinical protocols and radiographic equipment on pathology visibility and radiation dose using a neonatal chest phantom. Radiography (Lond) 2020; 26:282-287. [PMID: 32169312 DOI: 10.1016/j.radi.2020.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 02/15/2020] [Accepted: 02/19/2020] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Little is known about the variations in pathology visibility (PV) and their corresponding radiation dose values for neonatal chest radiography, between and within hospitals. Large variations in PV could influence the diagnostic outcome and the variations in radiation dose could affect the risk to patients. The aim of this study is to compare the PV and radiation dose for standard neonatal chest radiography protocols among a series of public hospitals. METHODS A Gammex 610 neonatal chest phantom was used to simulate the chest region of neonates. Radiographic acquisitions were conducted on 17 X-ray machines located in eight hospitals, utilising their current neonatal chest radiography protocols. Six qualified radiographers assessed PV visually using a relative visual grading analysis (VGA). Signal to noise ratios (SNR) and contrast to noise ratios (CNR) were measured as a measure of image quality (IQ). Incident air kerma (IAK) was measured using a solid-state dosimeter. RESULTS PV and radiation dose varied substantially between and within hospitals. For PV, the mean (range) VGA scores, between and within the hospitals, were 2.69 (2.00-3.50) and 2.73 (2.33-3.33), respectively. For IAK, the mean (range), between and within the hospitals, were 24.45 (8.11-49.94) μGy and 34.86 (22.26-49.94) μGy, respectively. CONCLUSION Between and within participating hospitals there was wide variation in the visibility of simulated pathology and radiation dose (IAK). IMPLICATIONS FOR PRACTICE X-ray units with lower PV and higher doses require optimisation of their standard clinical protocols. Institutions which can offer acceptable levels of PV but with lower radiation doses should help facilitate national optimisation processes.
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Affiliation(s)
- S Al-Murshedi
- University of ALZahraa for Women, College of Health and Medical Technology, Karbala, Iraq.
| | - Peter Hogg
- School of Health and Society, University of Salford, Salford, M6 6PU, United Kingdom
| | - A England
- School of Health and Society, University of Salford, Salford, M6 6PU, United Kingdom
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Shahgeldi K, Sjöberg T, Nordström J, Lesanu R, Svahn TM. OPTIMIZING IMAGE QUALITY, RADIATION DOSAGE TO THE PATIENT AND TO THE DETECTOR IN PEDIATRIC CHEST RADIOGRAPHY: A PHANTOM STUDY OF A PORTABLE DIGITAL RADIOGRAPHY SYSTEM. RADIATION PROTECTION DOSIMETRY 2019; 185:414-420. [PMID: 30916753 DOI: 10.1093/rpd/ncz028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/21/2018] [Accepted: 02/18/2019] [Indexed: 06/09/2023]
Abstract
The present work aimed to optimize exposure settings in pediatric digital chest radiography (DR) with regard to image quality and radiation dosage. A pediatric phantom was imaged with a portable DR unit to examine different exposure settings (range: 75-109 kVp; 0.3-1.28 mAs) for patients of 10-20 kg. Fourteen experienced radiologists compared the structural image quality of the images with a reference image (85 kVp/1.28 mAs). A multiple-reader multiple-case analysis of the radiologists' interpretations was performed. Effective dose was computed and standardized exposure indices (EIs) were extracted for the different exposure settings. For the lowest tube voltage setting (75 kVp/1.28 mAs), radiation dosage could be reduced with 35% relative the reference settings without compromising image quality (p > 0.05). EI was within recommendations (250 ± 100). Lower tube voltage in pediatric DR permitted a dose reduction at maintained quality for the physical aspects and diagnostic performance. Other weight-classes should be examined and adjusted accordingly.
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Affiliation(s)
- Kaveh Shahgeldi
- Centre for Research and Development, Uppsala University/Region Gävleborg, 80188 Gävle, Sweden
| | - Tommy Sjöberg
- Department of Surgical Science, Uppsala University, 75185 Uppsala, Sweden
| | - Jonny Nordström
- Centre for Research and Development, Uppsala University/Region Gävleborg, 80188 Gävle, Sweden
| | - Radu Lesanu
- Department of Imaging and Functional Medicine, Division Diagnostics, Gävle Hospital, Region Gävleborg, 80188 Gävle, Sweden
| | - Tony Martin Svahn
- Centre for Research and Development, Uppsala University/Region Gävleborg, 80188 Gävle, Sweden
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Jang JS, Yang HJ, Koo HJ, Kim SH, Park CR, Yoon SH, Shin SY, Do KH. Image quality assessment with dose reduction using high kVp and additional filtration for abdominal digital radiography. Phys Med 2018; 50:46-51. [PMID: 29891093 DOI: 10.1016/j.ejmp.2018.05.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 05/04/2018] [Accepted: 05/06/2018] [Indexed: 11/25/2022] Open
Abstract
PURPOSE Dose reduction using additional filters with high kilovoltage peak (kVp) for abdominal digital radiography has received much attention recently. We evaluated image quality with dose reduction in abdominal digital radiography by using high kVp and additional copper filters at a tertiary hospital. METHODS Between June 2016 and July 2016, 82 patients underwent abdominal digital radiography using 80 kVp in X-ray room 1 and 82 were imaged using 92 kVp with 0.1-mm copper filtration in X-ray room 2. The effective dose was calculated using a PC-based Monte Carlo program. Image quality of the abdominal radiography acquired in the two rooms was evaluated using a five-point ordinal scale, as well as the signal-to-noise and contrast-to-noise ratios. RESULTS The mean effective dose decreased by 25.8% and 25.7% for the supine and standing positions, respectively, when abdominal digital radiography using 92 kVp with 0.1-mm copper filtration was performed. In the 20 patients who performed abdominal digital radiography twice in each room, visual grading scores for visualisation of psoas outlines and kidney outlines are higher in room 1. However, there was no statistical significant difference of visual grading scores among the 124 patients who underwent only one abdominal radiography in the room 1 or 2 (P > 0.05). CONCLUSIONS Dose reduction for abdominal digital radiography can be achieved with comparable image quality by performing abdominal digital radiography using 92 kVp with 0.1-mm copper filtration, despite the higher AEC dose.
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Affiliation(s)
- Ji Sung Jang
- Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul, South Korea; Department of Medical Physics, Korea University, South Korea
| | - Hyung Jin Yang
- Department of Medical Physics, Korea University, South Korea
| | - Hyun Jung Koo
- Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul, South Korea
| | - Sung Ho Kim
- Department of Medical Physics, Korea University, South Korea
| | - Chan Rok Park
- Department of Medical Physics, Korea University, South Korea
| | - Suk Hwan Yoon
- Department of Medical Physics, Korea University, South Korea
| | - So Youn Shin
- Department of Radiology, Kyung Hee University Hospital, College of Medicine, Kyung Hee University, Seoul, South Korea
| | - Kyung-Hyun Do
- Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul, South Korea.
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Alejo L, Corredoira E, Sánchez-Muñoz F, Huerga C, Aza Z, Plaza-Núñez R, Serrada A, Bret-Zurita M, Parrón M, Prieto-Areyano C, Garzón-Moll G, Madero R, Guibelalde E. Radiation dose optimisation for conventional imaging in infants and newborns using automatic dose management software: an application of the new 2013/59 EURATOM directive. Br J Radiol 2018; 91:20180022. [PMID: 29537302 PMCID: PMC6223298 DOI: 10.1259/bjr.20180022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 03/01/2018] [Accepted: 03/12/2018] [Indexed: 01/24/2023] Open
Abstract
Objective: The new 2013/59 EURATOM Directive (ED) demands dosimetric optimisation procedures without undue delay. The aim of this study was to optimise paediatric conventional radiology examinations applying the ED without compromising the clinical diagnosis. METHODS Automatic dose management software (ADMS) was used to analyse 2678 studies of children from birth to 5 years of age, obtaining local diagnostic reference levels (DRLs) in terms of entrance surface air kerma. Given local DRL for infants and chest examinations exceeded the European Commission (EC) DRL, an optimisation was performed decreasing the kVp and applying the automatic control exposure. To assess the image quality, an analysis of high-contrast resolution (HCSR), signal-to-noise ratio (SNR) and figure of merit (FOM) was performed, as well as a blind test based on the generalised estimating equations method. RESULTS For newborns and chest examinations, the local DRL exceeded the EC DRL by 113%. After the optimisation, a reduction of 54% was obtained. No significant differences were found in the image quality blind test. A decrease in SNR (-37%) and HCSR (-68%), and an increase in FOM (42%), was observed. CONCLUSION ADMS allows the fast calculation of local DRLs and the performance of optimisation procedures in babies without delay. However, physical and clinical analyses of image quality remain to be needed to ensure the diagnostic integrity after the optimisation process. Advances in knowledge: ADMS are useful to detect radiation protection problems and to perform optimisation procedures in paediatric conventional imaging without undue delay, as ED requires.
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Affiliation(s)
- L Alejo
- Department of Medical Physics, La Paz University Hospital, Madrid, Spain
| | - E Corredoira
- Department of Medical Physics, La Paz University Hospital, Madrid, Spain
| | - F Sánchez-Muñoz
- Department of Medical Physics, La Paz University Hospital, Madrid, Spain
| | - C Huerga
- Department of Medical Physics, La Paz University Hospital, Madrid, Spain
| | - Z Aza
- Department of Medical Physics, La Paz University Hospital, Madrid, Spain
| | - R Plaza-Núñez
- Department of Medical Physics, La Paz University Hospital, Madrid, Spain
| | - A Serrada
- Department of Medical Physics, La Paz University Hospital, Madrid, Spain
| | - M Bret-Zurita
- Department of Paediatric Radiology, La Paz University Hospital, Madrid, Spain
| | - M Parrón
- Department of Paediatric Radiology, La Paz University Hospital, Madrid, Spain
| | - C Prieto-Areyano
- Department of Paediatric Radiology, La Paz University Hospital, Madrid, Spain
| | - G Garzón-Moll
- Department of Paediatric Radiology, La Paz University Hospital, Madrid, Spain
| | - R Madero
- Department of Biostatistics, La Paz University Hospital, Madrid, Spain
| | - E Guibelalde
- Department of Radiology, Complutense University, Madrid, Spain
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Can placing lead-rubber inferolateral to the light beam diaphragm limit ionising radiation to multiple radiosensitive organs? Radiography (Lond) 2017; 24:15-21. [PMID: 29306369 DOI: 10.1016/j.radi.2017.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 11/20/2022]
Abstract
INTRODUCTION This article investigates a practical method of reducing the impact of scattered radiation during a lateral radiographic projection of the elbow. The light beam diaphragm (LBD) is generally accepted to limit ionising radiation using horizontal and longitudinal lead shutters, yet this article evidences further dose limitation by placing lead-rubber inferolateral to the LBD device. METHODS Using an anthropomorphic phantom and arm construction scattered radiation was recorded at multiple radiosensitive organs. A 15 cc ionisation chamber (model 10100 AT TRIAD) was placed on each radiosensitive organ (eye, thyroid, breast, testes, spleen and ovaries) measuring exposure rate (μGy/s). Dose readings were recorded before and after the placement of lead-rubber inferolateral to the LBD. A paired two sample t-test was undertaken affirming how likely dose limitation was attributable to chance (p < 0.05). RESULTS Descriptive and inferential statistics demonstrate dose reduction to radiosensitive organs (right eye 53%, right breast 53%, left eye 39%, thyroid 13%, left ovary 9%, testes 6%, left breast 3% and spleen 2%) upon placement of the lead-rubber inferolateral to the LBD. The paired two sample t-test demonstrated statistically significant dose limitation (t = 2.04, df = 7, p = 0.04) thus significant for radiographic practice. CONCLUSION Placement of lead-rubber inferolateral to the LBD limits dose to multiple radiosensitive organs. Right (53%) and left (39%) eye lens, right breast (53%), thyroid (13%), left ovary (9%), testes (6%), left breast (3%) and spleen (2%) statistically demonstrate dose limiting opportunities to patients.
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Menser B, Manke D, Mentrup D, Neitzel U. A MONTE-CARLO SIMULATION FRAMEWORK FOR JOINT OPTIMISATION OF IMAGE QUALITY AND PATIENT DOSE IN DIGITAL PAEDIATRIC RADIOGRAPHY. RADIATION PROTECTION DOSIMETRY 2016; 169:371-377. [PMID: 26628612 DOI: 10.1093/rpd/ncv483] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In paediatric radiography, according to the as low as reasonably achievable (ALARA) principle, the imaging task should be performed with the lowest possible radiation dose. This paper describes a Monte-Carlo simulation framework for dose optimisation of imaging parameters in digital paediatric radiography. Patient models with high spatial resolution and organ segmentation enable the simultaneous evaluation of image quality and patient dose on the same simulated radiographic examination. The accuracy of the image simulation is analysed by comparing simulated and acquired images of technical phantoms. As a first application example, the framework is applied to optimise tube voltage and pre-filtration in newborn chest radiography. At equal patient dose, the highest CNR is obtained with low-kV settings in combination with copper filtration.
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Affiliation(s)
- Bernd Menser
- Philips Research, High Tech Campus 34, 5656 AE Eindhoven, The Netherlands
| | - Dirk Manke
- Diagnostic X-ray, Philips Healthcare DMC GmbH, Röntgenstraße 24, 22335 Hamburg, Germany
| | - Detlef Mentrup
- Diagnostic X-ray, Philips Healthcare DMC GmbH, Röntgenstraße 24, 22335 Hamburg, Germany
| | - Ulrich Neitzel
- Diagnostic X-ray, Philips Healthcare DMC GmbH, Röntgenstraße 24, 22335 Hamburg, Germany
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Ultrasound in the Diagnostics of Metaphyseal Forearm Fractures in Children: A Systematic Review and Cost Calculation. Pediatr Emerg Care 2016; 32:401-7. [PMID: 26087441 DOI: 10.1097/pec.0000000000000446] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Metaphyseal forearm fractures are a common occurrence in childhood accounting up to 20% of all pediatric fractures. The standard diagnostic procedure is an x-ray scan. Sonographic examinations could be an alternative that avoids exposition to ionizing radiation and possibly reduces pain, time, and costs. This is a systematic review of clinical studies evaluating ultrasound as a possible alternative to radiographs in diagnosing metaphyseal forearm fractures in children. METHODS A systematic literature research for diagnostic studies and reviews was conducted in EMBASE, MEDLINE, and the Cochrane Library in May 2013 and updated in May 2014. In addition, reference lists of publications included were scanned. Outcome parameters were diagnostic accuracy, costs, examination time, and the assessment of pain. The study population is defined as children, because forearm fractures are very common in this age group and the impact of radiation on younger patients is greater than that on adults. Methodological quality of the studies has been assessed with Quality Assessment of Diagnostic Accuracy Studies-2. In addition, we carried out a cost center accounting. RESULTS Eight diagnostic studies and 2 reviews were included in the analysis. The risk of bias of 4 studies was low; and of the other 4 ones, it was moderate. Critical aspects were missing or inaccurate blinding and insufficient descriptions of the study protocol, especially the order of examinations.Twenty-six to 115 patients within the age of 0 to 21 years were included in the studies. Sensitivity ranged from 64% to 100% and specificity did between 73% and 100%. Sensitivity was in six studies and specificity was in seven studies higher than 90%.Chaar-Alvarez et al reported an average time reduction of 25 minutes by using sonography instead of x-ray and a reduction of pain from 1.7 to 1.2 points on a visual analog scale (0-5 points). In 2 other studies, all patients reported pain-free sonographic examinations. The results of the cost center accounting, not being representative, were costs of &OV0556;20.54 per examination with ultrasound and &OV0556;26.60 per radiography-based one, which is a potential saving of 22.79% by replacing radiographic examinations by ultrasound. CONCLUSIONS Sensitivity and specificity of ultrasound examinations are high. Single study results show that sonographic examinations can be faster and less painful. In addition, the calculation model shows a tendency towards less-expensive ultrasound examinations.Further studies are needed with an adequate sample size calculation for assessing equivalence or non-inferiority of ultrasound and x-ray and to collect data on pain, examination time, and costs. The age of the older participants may be problematic because of the fact that epiphyseal plates close within the age from 15 to 22 years, which may influence the diagnostic accuracy of sonographic examinations. Therefore, future studies should contain age-stratified analyses. In addition, the calculation model for costs should be tested on a wider data base.
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Diagnostic reference levels in plain radiography for paediatric imaging: A Portuguese study. Radiography (Lond) 2016. [DOI: 10.1016/j.radi.2015.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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