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Valentin B, Kamp B, Henke J, Ljimani A, Appel E, Antoch G, Steuwe A. Influence of tube and patient positioning in thoracoabdominal CT examinations on radiation exposure-towards a better patient positioning. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2023; 43:031512. [PMID: 37619552 DOI: 10.1088/1361-6498/acf384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 08/24/2023] [Indexed: 08/26/2023]
Abstract
Although iso-centric patient positioning is enormously important in computed tomography (CT), it is complicated in thoracoabdominal imaging by the varying dimensions of the body. Patient positioning can affect the appearance of the patient on the localiser. Positioned too close to the x-ray tube, a patient appears considerably more voluminous. The goal of this study is to assess the difference in radiation exposure of combined chest and abdomen CT scans between scans with prior 0°- and 180°-localisers in conjunction with patient positioning. In this IRB-approved retrospective study, patients who had two routine thoracoabdominal CT scans on the same CT scanner, one with a prior 0°- and one with a prior 180°-localiser, were included. To evaluate the radiation exposure of the thoracoabdominal CT examination regarding the tube position during the localiser, volumetric computed tomography dose index (CTDIvol), size-specific dose estimate (SSDE), patient diameter and positioning within the iso-centre for three positions (heart, abdomen, femur level) were compared with regard to the tube position during the prior localiser. CT examinations of 114 patients were included. Despite similar patient weight and diameter between the two examinations, SSDE and CTDIvolwas significantly larger (up to 73%) with 180°-localisers. Patient offset from the iso-centre ranged between -9 mm at the centre slice (abdomen level) to -43 mm at the most caudal slice at the pelvis (femur level), causing a significant magnification (p < 0.001) on 180°-localisers with a subsequent increase of the apparent attenuation. The results of this study emphasise the use of 0°-localisers in thoracoabdominal CTs, since 180°-localisers caused patient magnification with subsequent increase in radiation exposure. The advantage of 180°-localisers, namely reducing the dose in thyroid and breast, is eliminated if the dose of the CT scan increases significantly in the abdomen and pelvis.
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Affiliation(s)
- Birte Valentin
- University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf D-40225, Germany
| | - Benedikt Kamp
- University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf D-40225, Germany
| | - Jan Henke
- University Dusseldorf, Medical Faculty, Department of Nuclear Medicine, Dusseldorf D-40225, Germany
| | - Alexandra Ljimani
- University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf D-40225, Germany
| | - Elisabeth Appel
- University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf D-40225, Germany
| | - Gerald Antoch
- University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf D-40225, Germany
| | - Andrea Steuwe
- University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf D-40225, Germany
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Urikura A, Miyauchi Y, Yoshida T, Ishita Y, Takiguchi K, Endo M, Aramaki T. Patient dose increase caused by posteroanterior CT localizer radiographs. Radiography (Lond) 2023; 29:334-339. [PMID: 36709524 DOI: 10.1016/j.radi.2023.01.009] [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: 11/07/2022] [Revised: 01/09/2023] [Accepted: 01/12/2023] [Indexed: 01/28/2023]
Abstract
INTRODUCTION The aim of this study was to compare the output dose (volume CT dose index [ CTDIvol], and dose length product [DLP]) of automatic tube current modulation (ATCM) determined by localizer radiographs obtained in the anteroposterior (AP) and posteroanterior (PA) directions. METHODS One hundred and twenty-four patients who underwent upper abdomen and/or chest-to-pelvis computed tomography (CT) were included. Patients underwent two series of CT examinations, and localizer radiographs were obtained in the AP and PA directions. The horizontal diameter of the localizer radiograph, scan length, CTDIvol, and DLP were measured. RESULTS There was no significant difference in the scan length; however, all the other values were significantly higher in the PA direction. The mean horizontal diameter was 33.1 ± 2.6 cm and 35.4 ± 2.9 cm in the AP and PA directions of the localizer radiographs, respectively. The CTDIvol and DLP in the PA direction increased by approximately 7-8%. Bland-Altman plots between AP and PA localizer directions in upper abdominal CT showed a positive bias of 1.1 mGy and 30.0 mGy cm for CTDIvol and DLP, respectively. Correspondingly, chest-to-pelvic CT showed a positive bias of 0.93 mGy and 69.3 mGy cm for CTDIvol and DLP, respectively. CONCLUSION The output dose of ATCM determined by localizer radiographs obtained in the PA direction was increased compared to the AP direction. Localizer radiographs obtained in the AP direction should be preferred for optimizing the output dose using ATCM. IMPLICATIONS FOR PRACTICE Based on the evidence of this study, localizer radiographs obtained in the AP direction should be preferred for optimizing the output dose in CT examinations.
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Affiliation(s)
- Atsushi Urikura
- Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi, Sunto, Shizuoka 411-8777, Japan; Department of Radiological Technology, Radiological Diagnosis, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
| | - Yosuke Miyauchi
- Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi, Sunto, Shizuoka 411-8777, Japan.
| | - Tsukasa Yoshida
- Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi, Sunto, Shizuoka 411-8777, Japan.
| | - Yuya Ishita
- Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi, Sunto, Shizuoka 411-8777, Japan.
| | - Keisuke Takiguchi
- Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi, Sunto, Shizuoka 411-8777, Japan.
| | - Masahiro Endo
- Division of Comprehensive Radiology Center, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8677, Japan.
| | - Takeshi Aramaki
- Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi, Sunto, Shizuoka 411-8777, Japan; Division of Interventional Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777, Japan.
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Jiang D, Wang Y, Zhang P, Liu Z. Comparison of image quality and radiation dose of different scanning methods used for computed tomography of the unilateral shoulder. Acta Radiol 2023; 64:1919-1926. [PMID: 36775984 DOI: 10.1177/02841851231153031] [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: 02/14/2023]
Abstract
BACKGROUND The effect of different computed tomography (CT) scanning methods of the shoulder on image quality is uncertain. PURPOSE To compare the effect of different methods of CT scanning of the right shoulder on image quality and radiation dose. MATERIAL AND METHODS A total of 30 adults were divided into five groups. Group A received scans centered on the body's long axis, a scout direction of 0° + 90°, and automatic tube current modulation (ATCM). The other four groups (B, C, D, E) received isocenter scans centered on the shoulder with different scout directions (B and C: 0° + 90°, D: 0°, E: 0° + 270°) and tube currents (B: 420 mA; C, D, E: ATCM). The volume CT dose index (CTDIvol), dose-length product (DLP), image objective noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were compared. Three subjective measures were also compared (noise, stripe artifacts, diagnostic confidence). RESULTS The five groups differed significantly in all subjective and objective indexes. The CTDIvol and DLP decreased in the order of groups C, A, B, E, and D; the differences between groups A and B were not significant (P > 0.05). Groups B, C, and E had better SNR and CNR than groups A and D (P < 0.01). Subjective evaluations indicated group D was worse than groups B, C, and E (P < 0.05). CONCLUSION In the ATCM system that uses the last scout view, CT of the shoulder should use isocenter scanning with the lateral scout view when the tube is away from the long axis of the body as the last execution direction.
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Affiliation(s)
- Dongdong Jiang
- Department of Radiology, Wuhan Fourth Hospital, Wuhan, Hubei, PR China
| | - Yanan Wang
- Imaging Center, Wuhan Children's Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Peng Zhang
- Department of Radiology, Wuhan Fourth Hospital, Wuhan, Hubei, PR China
| | - Zhenyu Liu
- Department of Radiology, Wuhan Fourth Hospital, Wuhan, Hubei, PR China
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Al-Hayek Y, Zheng X, Hayre C, Spuur K. The influence of patient positioning on radiation dose in CT imaging: A narrative review. J Med Imaging Radiat Sci 2022; 53:737-747. [PMID: 36280573 DOI: 10.1016/j.jmir.2022.09.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 09/21/2022] [Accepted: 09/29/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND PURPOSE Although it is fundamental for optimal scanner operation, it is generally accepted that accurate patient centring cannot always be achieved. This review aimed to examine the reported knowledge of the negative impact of patient positioning on radiation dose and image quality during CT imaging. Furthermore, the study evaluated the current optimisation tools and techniques used to improve patient positioning relative to the gantry iso-center. METHODOLOGY A comprehensive search through the databases PubMed, Ovid, and Google Scholar was performed. Keywords included patient off-centring, patient positioning, localiser radiograph orientation, radiation dose, and automatic patient positioning (including synonyms). The search was limited to full-text articles that were written in English. After initial title and abstract screening, a total of 52 articles were identified to address the aim of the review. No limitations were imposed on the year of publication. RESULTS Vertical off-centring was reported in up to 95% of patients undergoing chest and abdominal CT examinations, showing a significant influence on radiation dose. Depending on the scanner model and vendor, localiser orientation, bowtie filter used, and patient size, radiation dose varied from a decrease of 36% to an increase of 91%. A significant dose reduction was demonstrated when utilising an AP localiser, aligning with the trend for radiographers to off-center patients below the gantry iso-centre. Utilizing a 3D camera for body contour detection allowed for more accurate patient positioning and promoted further dose reduction. CONCLUSION Patient positioning has shown significant effects on radiation dose and image quality in CT. Developing a good understanding of the key factors influencing patient dose (off-centring direction, localiser orientation, patient size and bowtie filter selection) is critical in optimising CT scanning practices. Utilising a 3D camera for body contour detection is strongly recommended to improve patient positioning accuracy, image quality and to minimise patient dose.
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Affiliation(s)
- Yazan Al-Hayek
- School of Dentistry and Medical Sciences, Faculty of Science and Health, Charles Sturt University, Wagga Wagga, NSW, 2650, Australia; Department of Medical Imaging, Faculty of Applied Health Sciences, The Hashemite University, Zarqa, 13133, Jordan.
| | - Xiaoming Zheng
- School of Dentistry and Medical Sciences, Faculty of Science and Health, Charles Sturt University, Wagga Wagga, NSW, 2650, Australia.
| | - Christopher Hayre
- Department of Medical Imaging, College of Medicine and Health, University of Exeter, Devon, UK.
| | - Kelly Spuur
- School of Dentistry and Medical Sciences, Faculty of Science and Health, Charles Sturt University, Wagga Wagga, NSW, 2650, Australia.
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Metal implants influence CT scan parameters leading to increased local radiation exposure: A proposal for correction techniques. PLoS One 2019; 14:e0221692. [PMID: 31442288 PMCID: PMC6707604 DOI: 10.1371/journal.pone.0221692] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 08/13/2019] [Indexed: 12/14/2022] Open
Abstract
Metal implants not only deteriorate image quality, but also increase radiation exposure. The purpose of this study was to evaluate the effect of metal hip prosthesis on absorbed radiation dose and assess the efficacy of organ dose modulation (ODM) and metal artifact reduction (MAR) protocols on dose reduction. An anthropomorphic phantom was scanned with and without bilateral metal hip prostheses, and surface and deep level radiation doses were measured at the abdomen and pelvis. Finally, the absorbed radiation doses at pelvic and abdominal cavities in the reference, ODM, and two MAR scans (Gemstone spectral imaging, GE) were compared. The Mann Whitney-U test and Kruskal-Wallis test were performed to compare the volume CT dose index (CTDIvol) and mean absorbed radiation doses. Unilateral and bilateral metal hip prostheses increased CTDIVOL by 14.4% and 30.5%, respectively. MAR protocols decreased absorbed radiation doses in the pelvis. MAR showed the most significant dose reduction in the deep pelvic cavity followed by ODM. However, MAR protocols increased absorbed radiation doses in the upper abdomen. ODM significantly reduced absorbed radiation in the pelvis and abdomen. In conclusion, metal hip implants increased radiation doses in abdominopelvic CT scans. MAR and ODM techniques reduced absorbed radiation dose in abdominopelvic CT scans with metal hip prostheses.
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Akin-Akintayo OO, Alexander LF, Neill R, Krupinksi EA, Tang X, Mittal PK, Small WC, Moreno CC. Prevalence and Severity of Off-Centering During Diagnostic CT: Observations From 57,621 CT scans of the Chest, Abdomen, and/or Pelvis. Curr Probl Diagn Radiol 2019; 48:229-234. [DOI: 10.1067/j.cpradiol.2018.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 02/20/2018] [Accepted: 02/21/2018] [Indexed: 11/22/2022]
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Forbrig R, Geyer LL, Stahl R, Thorsteinsdottir J, Schichor C, Kreth FW, Patzig M, Herzberg M, Liebig T, Dorn F, Trumm CG. Radiation dose and image quality in intraoperative CT (iCT) angiography of the brain with stereotactic head frames. Eur Radiol 2019; 29:2859-2867. [PMID: 30635759 DOI: 10.1007/s00330-018-5930-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/06/2018] [Accepted: 11/28/2018] [Indexed: 01/04/2023]
Abstract
OBJECTIVES Intraoperative CT (iCT) angiography of the brain with stereotactic frames is an integral part of navigated neurosurgery. Validated data regarding radiation dose and image quality in these special examinations are not available. We therefore investigated two iCT protocols in this IRB-approved study. METHODS Retrospective analysis of patients, who received a cerebral stereotactic iCT angiography on a 128 slice CT scanner between February 2016 and December 2017. In group A, automated tube current modulation (ATCM; reference value 410 mAs) and automated tube voltage selection (reference value 120 kV) were enabled, and only examinations with a selected voltage of 120 kV were included. In group B, fixed parameters were applied (300 mAs, 120 kV). Radiation dose was measured by assessing the volumetric CT dose index (CTDIvol), dose length product (DLP) and effective dose (ED). Signal-to-noise ratio (SNR) and image noise were assessed for objective image quality, visibility of arteries and grey-white differentiation for subjective image quality. RESULTS Two hundred patients (n = 100 in each group) were included. In group A, median selected tube current was 643 mAs (group B, 300 mAs; p < 0.001). Median values of CTDIvol, DLP and ED were 91.54 mGy, 1561 mGy cm and 2.97 mSv in group A, and 43.15 mGy, 769 mGy cm and 1.46 mSv in group B (p < 0.001). Image quality did not significantly differ between groups (p > 0.05). CONCLUSIONS ATCM yielded disproportionally high radiation dose due to substantial tube current increase at the frame level, while image quality did not improve. Thus, ATCM should preferentially be disabled. KEY POINTS • Automated tube current modulation (ATCM) yields disproportionally high radiation dose in intraoperative CT angiography of the brain with stereotactic head frames. • ATCM does not improve overall image quality in these special examinations. • ATCM is not yet optimised for CT angiography of the brain with major extracorporeal foreign materials within the scan range.
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Affiliation(s)
- Robert Forbrig
- Institute of Neuroradiology, University Hospital, LMU Munich, Marchioninistrasse 15, 81377, Munich, Germany.
| | - Lucas L Geyer
- Center of Radiology and Neuroradiology, Klinikum Ingolstadt, Ingolstadt, Germany
| | - Robert Stahl
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | | | - Christian Schichor
- Department of Neurosurgery, University Hospital, LMU Munich, Munich, Germany
| | | | - Maximilian Patzig
- Institute of Neuroradiology, University Hospital, LMU Munich, Marchioninistrasse 15, 81377, Munich, Germany
| | - Moriz Herzberg
- Institute of Neuroradiology, University Hospital, LMU Munich, Marchioninistrasse 15, 81377, Munich, Germany
| | - Thomas Liebig
- Institute of Neuroradiology, University Hospital, LMU Munich, Marchioninistrasse 15, 81377, Munich, Germany
| | - Franziska Dorn
- Institute of Neuroradiology, University Hospital, LMU Munich, Marchioninistrasse 15, 81377, Munich, Germany
| | - Christoph G Trumm
- Institute for Diagnostic and Interventional Radiology, Neuroradiology and Nuclear Medicine, Städtisches Klinikum München Harlaching, Munich, Germany
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Paolicchi F, Bastiani L, Negri J, Caramella D. Effect of CT Localizer Radiographs on Radiation Dose Associated With Automatic Tube Current Modulation: A Multivendor Study. Curr Probl Diagn Radiol 2019; 49:34-41. [PMID: 30704769 DOI: 10.1067/j.cpradiol.2018.12.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 12/15/2018] [Accepted: 12/31/2018] [Indexed: 11/22/2022]
Abstract
OBJECTIVES To assess the influence of the CT localizer radiograph on the automatic tube current modulation system of 7 CT scanners produced by 4 different CT manufacturers. METHODS The influence of the localizer orientation, table height, tube current and tube potential values on the radiation dose of the related CT scan were evaluated. Images were acquired by using an anthropomorphic phantom positioned in the CT gantry isocenter as well as from -6 cm to +6 cm vertically to the isocenter. RESULTS Vertical movement of the CT table height affected the radiation dose in all scanners using anterior-posterior or a posterior-anterior localizer orientation albeit differently, depending on the manufacturer; only in 1/7 scanner no influence was observed. The latero-lateral localizer orientation proved to be more effective in limiting the influence of the vertical miscentering in all scanners. Changing localizer's tube voltage influenced the scan radiation dose in scanners produced by two manufacturers, while no significant effect was observed in scanners produced by the other two manufacturers. No significant dose variation was observed in 6/7 scanners when changing the localizer's tube current. CONCLUSION Localizer radiograph shows a significant influence on the radiation exposure but with different outcomes depending on the manufacturer of the CT scanner. Radiologists and radiographers should have a thorough understanding of these differences to assure patients the best examination in terms of radiation dose and image quality.
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Affiliation(s)
- Fabio Paolicchi
- Department of Diagnostic and Interventional Radiology, University of Pisa, Pisa, Italy.
| | - Luca Bastiani
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Jacopo Negri
- Department of Radiology, Macerata General Hospital, Macerata, Italy
| | - Davide Caramella
- Department of Diagnostic and Interventional Radiology, University of Pisa, Pisa, Italy
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Inoue Y, Nagahara K, Inoki Y, Hara T, Miyatake H. Clinical evaluation of CT radiation dose in whole-body 18F-FDG PET/CT in relation to scout imaging direction and arm position. Ann Nucl Med 2018; 33:169-176. [DOI: 10.1007/s12149-018-1318-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 11/06/2018] [Indexed: 10/27/2022]
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Peng W, Li Z, Xia C, Guo Y, Zhang J, Zhang K, Li L, Zhao F. A CONSORT-compliant prospective randomized controlled trial: radiation dose reducing in computed tomography using an additional lateral scout view combined with automatic tube current modulation: Phantom and patient study. Medicine (Baltimore) 2017; 96:e7324. [PMID: 28746180 PMCID: PMC5627806 DOI: 10.1097/md.0000000000007324] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Revised: 05/26/2017] [Accepted: 05/29/2017] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Radiation exposure has been a hot point in research field of computed tomography (CT). Recently, automated tube current modulation (ATCM) has emerged as an important technique to reduce radiation exposure. Many studies have shown that the difference in scout view would affect modulation. This prospective randomized controlled study is aimed to investigate the impact of an additional lateral scout view on radiation dose and image quality in CT using ACTM. METHODS Combined with ATCM (Care Dose 4D) on multidetector CT, 2 thoracic phantom CT image series were acquired in which planning was conducted with either an anteroposterior (AP) or an AP-lateral scout view. Also, 410 patients underwent thoracic CT examinations using Care Dose 4D modulation and were randomized to either a scan planned with an AP-lateral scout or a single AP scout. Effects of the different scout views on applied effective milliampere seconds (mAs), volume CT dose index (CTDIvol) and dose-length-product (DLP) were analyzed. The quality of patient CT images was also assessed. Data were analyzed using independent t tests and linear correlation analysis. RESULTS Compared with AP groups, the mean CTDIvol (phantom, 0.89 ± 0.08 vs 1.36 ± 0.26 mGy, P < .001; in patients, 1.12 [0.96, 1.34] vs 2.16 [1.66, 2.64] mGy, P < .001) and DLP (in phantom, 26 [23.25, 28] vs 40 [34.25, 48] mGy×cm, P < .001; in patients, 41 [33, 41] vs 77 [60.5, 99.5] mGy×cm, P < .001) were significantly reduced by approximately 50% in AP-lateral scout view group. With the AP-lateral topogram, the radiation dose on different off-center positions was essentially equal (CTDIvol: 0.76-0.99 mGy; DLP: 22-28 mGy×cm effective dose: 0.31-0. 39 mSv). For image quality, contrast-to-noise ratio and signal-to-noise ratio values in the AP group were similar to those of AP-lateral scout view group. CONCLUSION AP combined with an additional lateral scout view using ACTM can significantly reduce the radiation dose without compromising image quality in chest screening CT.
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Affiliation(s)
- Wanlin Peng
- Department of Radiology, West China Hospital of Sichuan University, Chengdu
| | - Zhenlin Li
- Department of Radiology, West China Hospital of Sichuan University, Chengdu
| | - Chunchao Xia
- Department of Radiology, West China Hospital of Sichuan University, Chengdu
| | - Yingkun Guo
- Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Chengdu, China
| | - Jinge Zhang
- Department of Radiology, West China Hospital of Sichuan University, Chengdu
| | - Kai Zhang
- Department of Radiology, West China Hospital of Sichuan University, Chengdu
| | - Lei Li
- Department of Radiology, West China Hospital of Sichuan University, Chengdu
| | - Fei Zhao
- Department of Radiology, West China Hospital of Sichuan University, Chengdu
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