1
|
Systematic assessment of coronary calcium detectability and quantification on four generations of CT reconstruction techniques: a patient and phantom study. Int J Cardiovasc Imaging 2023; 39:221-231. [PMID: 36598691 DOI: 10.1007/s10554-022-02703-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 07/24/2022] [Indexed: 01/07/2023]
Abstract
In computed tomography, coronary artery calcium (CAC) scores are influenced by image reconstruction. The effect of a newly introduced deep learning-based reconstruction (DLR) on CAC scoring in relation to other algorithms is unknown. The aim of this study was to evaluate the effect of four generations of image reconstruction techniques (filtered back projection (FBP), hybrid iterative reconstruction (HIR), model-based iterative reconstruction (MBIR), and DLR) on CAC detectability, quantification, and risk classification. First, CAC detectability was assessed with a dedicated static phantom containing 100 small calcifications varying in size and density. Second, CAC quantification was assessed with a dynamic coronary phantom with velocities equivalent to heart rates of 60-75 bpm. Both phantoms were scanned and reconstructed with four techniques. Last, scans of fifty patients were included and the Agatston calcium score was calculated for all four reconstruction techniques. FBP was used as a reference. In the phantom studies, all reconstruction techniques resulted in less detected small calcifications, up to 22%. No clinically relevant quantification changes occurred with different reconstruction techniques (less than 10%). In the patient study, the cardiovascular risk classification resulted, for all reconstruction techniques, in excellent agreement with the reference (κ = 0.96-0.97). However, MBIR resulted in significantly higher Agatston scores (61 (5.5-435.0) vs. 81.5 (9.25-435.0); p < 0.001) and 6% reclassification rate. In conclusion, HIR and DLR reconstructed scans resulted in similar Agatston scores with excellent agreement and low-risk reclassification rate compared with routine reconstructed scans (FBP). However, caution should be taken with low Agatston scores, as based on phantom study, detectability of small calcifications varies with the used reconstruction algorithm, especially with MBIR and DLR.
Collapse
|
2
|
Madaj P, Li D, Nakanishi R, Andreini D, Pontone G, Conte E, O'Rourke R, Hamilton-Craig C, Nimmagadda M, Kim N, Fatima B, Dailing C, Shaikh K, Shekar C, Lee JH, Budoff MJ. Radiation Doses in Patients Undergoing Computed Tomographic Coronary Artery Calcium Evaluation With a 64-Slice Scanner Versus a 256-Slice Scanner. Tex Heart Inst J 2022; 49:478371. [PMID: 35244722 DOI: 10.14503/thij-18-6793] [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: 11/23/2022]
Abstract
Computed tomographic coronary artery calcium scanning enables cardiovascular risk stratification; however, exposing patients to high radiation levels is an ongoing concern. New-generation computed tomographic systems use lower radiation doses than older systems do. To quantify comparative doses of radiation exposure, we prospectively acquired images from 220 patients with use of a 64-slice GE LightSpeed VCT scanner (control group, n=110) and a 256-slice GE Revolution scanner (study group, n=110). The groups were matched for age, sex, and body mass index; statistical analysis included t tests and linear regression. The mean dose-length product was 21% lower in the study group than in the control group (60.2 ± 27 vs 75.9 ± 22.6 mGy·cm; P <0.001) and also in each body mass index subgroup. Similarly, the mean effective radiation dose was 21% lower in the study group (0.84 ± 0.38 vs 1.06 ± 0.32 mSv) and lower in each weight subgroup. After adjustment for sex, women in the study group had a lower dose-length product (50.4 ± 23.4 vs 64.7 ± 27.6 mGy·cm) than men did and received a lower effective dose (0.7 ± 0.32 vs 0.9 ± 0.38 mSv) (P=0.009). As body mass index and waist circumference increased, so did doses for both scanners. Our study group was exposed to radiation doses lower than the previously determined standard of 1 mSv, even after adjustment for body mass index and waist circumference. In 256-slice scanning for coronary artery calcium, radiation doses are now similar to those in lung cancer screening and mammography.
Collapse
Affiliation(s)
- Paul Madaj
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Dong Li
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Rine Nakanishi
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California.,Department of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine, Tokyo, Japan
| | - Daniele Andreini
- Department of Cardiology, Centro Cardiologico Monzino, Istituto di Ricovero e Cura a Carattere Scientifico, Milan, Italy
| | - Gianluca Pontone
- Department of Cardiology, Centro Cardiologico Monzino, Istituto di Ricovero e Cura a Carattere Scientifico, Milan, Italy
| | - Edoardo Conte
- Department of Cardiology, Centro Cardiologico Monzino, Istituto di Ricovero e Cura a Carattere Scientifico, Milan, Italy
| | - Rachael O'Rourke
- Department of Medical Imaging, The Prince Charles Hospital, Brisbane, Queensland, Australia.,Department of Cardiology, University of Queensland, Brisbane, Australia
| | | | - Manojna Nimmagadda
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Nicholas Kim
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Badiha Fatima
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Christopher Dailing
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Kashif Shaikh
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Chandana Shekar
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Ju Hwan Lee
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| | - Matthew J Budoff
- Department of Medicine, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, California
| |
Collapse
|
3
|
Izoe Y, Nagao M, Tokai M, Hashimoto H, Tanaka I, Chida K. Radiation dose for 320-row dose-modulated dynamic coronary CT angiography. J Appl Clin Med Phys 2021; 22:307-312. [PMID: 34375023 PMCID: PMC8425931 DOI: 10.1002/acm2.13390] [Citation(s) in RCA: 3] [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: 05/10/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES The area detector 320-row CT scanner, which can cover the whole heart in one rotation, can aid in reducing radiation exposure during electrocardiography (ECG)-gated coronary CT angiography (CCTA). Recently, researchers have proposed dose-modulated dynamic CCTA with a 320-row scanner for the detection of functional myocardial ischemia. In the present study, we compared and validated the radiation dose of this method with that of the standard CCTA method and the latest diagnostic reference levels (DRLs). MATERIALS AND METHODS The study included a total of 164 consecutive patients with suspected or known coronary artery disease (CAD) who underwent CCTA with a 320-row scanner. The patients were randomly divided into dynamic and standard CCTA groups, and the CT dose index (CTDIvol) and dose length product (DLP) calculated by the CT system were compared between the two protocols and with the latest DRL. RESULTS Standard and dynamic CCTA scans were performed in 77 and 87 patients, respectively. CTDIvol was significantly higher for standard CCTA than for dynamic CCTA (41 ± 35 mGy vs. 22 ± 7 mGy, p = 0.0014). DLP was also significantly higher for standard CCTA than for dynamic CCTA (864 ± 702 mGy × cm vs. 434 ± 106 mGy × cm, p < .0001). For standard scans, CTDIvol and DLP exceeded the 2020 DRL in Japan in 16% (12/77) and 17% (13/77) of cases, respectively. In contrast, rates for the dynamic scan were only 1% (1/87) for CTDIvol and 0% (0/87) for DLP. CONCLUSION The dose of radiation exposure during dynamic CCTA with a 320-row scanner does not exceed that of standard CCTA and is sufficient to meet the latest DRL. Thus, our results suggest that the method is safe from the perspective of radiation exposure.
Collapse
Affiliation(s)
- Yukako Izoe
- Graduate School of Medicine, Health SciencesDivision of Radiological Examination and TechnologyTohoku UniversitySendai CityJapan
| | - Michinobu Nagao
- Department of Diagnostic imaging & Nuclear MedicineTokyo Women’s Medical UniversityTokyoJapan
| | - Mei Tokai
- Department of Radiological ServiceTokyo Women’s Medical UniversityTokyoJapan
| | - Hiroyuki Hashimoto
- Department of Radiological ServiceTokyo Women’s Medical UniversityTokyoJapan
| | - Isao Tanaka
- Department of Radiological ServiceTokyo Women’s Medical UniversityTokyoJapan
| | - Koichi Chida
- Graduate School of Medicine, Health SciencesDivision of Radiological Examination and TechnologyTohoku UniversitySendai CityJapan
| |
Collapse
|
4
|
Madaj P, Li D, Nakanishi R, Andreini D, Pontone G, Conte E, O’Rourke Franzcr R, Hamilton-Craig C, Nimmagadda M, Kim N, Fatima B, Dailing C, Budoff MJ. Lower Radiation Dosing in Cardiac CT Angiography: The CONVERGE Registry. J Nucl Med Technol 2020; 48:58-62. [DOI: 10.2967/jnmt.119.229500] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 08/05/2019] [Indexed: 11/16/2022] Open
|
5
|
Enhanced radiation exposure associated with anterior-posterior x-ray tube position in young women undergoing cardiac computed tomography. Am Heart J 2019; 215:91-94. [PMID: 31295633 DOI: 10.1016/j.ahj.2019.05.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 05/08/2019] [Indexed: 12/22/2022]
Abstract
Given the current increase in the incidence of coronary artery disease in younger women as well as the high lifetime risk of developing an x-ray-induced malignancy in this population, we aimed at assessing chest radiation in 206 women ≤55 years old undergoing coronary calcium scoring (CACS) by using a Monte Carlo simulation tool. Our data indicate that the simulated radiation dose of the female breast during CACS depends substantially on the starting position of the x-ray tube, with an almost 2 times excess of breast radiation exposure being measured during anterior-posterior tube positioning. Thus, an additional technical feature taking into account the position of the x-ray tube when acquisition is triggered might be an important tool to reduce radiation exposure of the female breast during CACS.
Collapse
|
6
|
Choi AD, Leifer ES, Yu JH, Datta T, Bronson KC, Rollison SF, Schuzer JL, Steveson C, Shanbhag SM, Chen MY. Reduced radiation dose with model based iterative reconstruction coronary artery calcium scoring. Eur J Radiol 2019; 111:1-5. [DOI: 10.1016/j.ejrad.2018.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 12/03/2018] [Accepted: 12/07/2018] [Indexed: 02/06/2023]
|
7
|
Vonder M, van der Werf NR, Leiner T, Greuter MJ, Fleischmann D, Vliegenthart R, Oudkerk M, Willemink MJ. The impact of dose reduction on the quantification of coronary artery calcifications and risk categorization: A systematic review. J Cardiovasc Comput Tomogr 2018; 12:352-363. [DOI: 10.1016/j.jcct.2018.06.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 05/18/2018] [Accepted: 06/11/2018] [Indexed: 11/29/2022]
|
8
|
Tang YC, Liu YC, Hsu MY, Tsai HY, Chen CM. Adaptive Iterative Dose Reduction 3D Integrated with Automatic Tube Current Modulation for CT Coronary Artery Calcium Quantification: Comparison to Traditional Filtered Back Projection in an Anthropomorphic Phantom and Patients. Acad Radiol 2018; 25:1010-1017. [PMID: 29395796 DOI: 10.1016/j.acra.2017.12.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 12/20/2017] [Accepted: 12/23/2017] [Indexed: 01/05/2023]
Abstract
RATIONALE AND OBJECTIVES We aimed to evaluate integrated adaptive iterative dose reduction 3D (AIDR 3D) algorithm in automatic tube current modulation (ATCM) for the quantification of coronary artery calcium score (CACS) and cardiac risk stratification. MATERIALS AND METHODS A thoracic phantom with calcium inserts of known densities was scanned with filtered back projection (FBP) and AIDR 3D algorithms in small- and medium-sized phantoms. Twenty-four patients underwent two consecutive scans of CACS with FBP and AIDR 3D algorithms. The absolute Agatston score, Agatston score risk, volume score, and Agatston score percentile-based risk were compared, and concordance coefficients and agreement plots were made. RESULTS Agatston and volume scores were significantly different between the phantom sizes (P < .01). There were no significant differences in the Agatston scores between FBP and AIDR 3D for the medium phantoms (P = .25). In the patients, there were no significant differences in Agatston and volume scores between FBP and AIDR 3D (P = .06 and P = .09, respectively). The correlation coefficients of Agatston and volume scores with AIDR 3D were excellent compared to those of FBP. There were no significant differences in Agatston score risk and Agatston score percentile-based risk between FBP and AIDR 3D (P = .74 and P = 1, respectively). There was mean dose reduction of 57.8% ± 18.6% for AIDR 3D. CONCLUSION The absolute Agatston score differed between FBP and AIDR 3D reconstructions. However, the cardiac risk categorizations of the two methods were comparable. An integrated AIDR 3D algorithm with automatic tube current modulation enables radiation dose savings at a consistent noise level without sacrificing CACS.
Collapse
|
9
|
Tesche C, Duguay TM, Schoepf UJ, van Assen M, De Cecco CN, Albrecht MH, Varga-Szemes A, Bayer RR, Ebersberger U, Nance JW, Thilo C. Current and future applications of CT coronary calcium assessment. Expert Rev Cardiovasc Ther 2018; 16:441-453. [PMID: 29734858 DOI: 10.1080/14779072.2018.1474347] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
INTRODUCTION Computed tomographic (CT) coronary artery calcium scoring (CAC) has been validated as a well-established screening method for cardiovascular risk stratification and treatment management that is used in addition to traditional risk factors. The purpose of this review is to present an update on current and future applications of CAC. Areas covered: The topic of CAC is summarized from its introduction to current application with focus on the validation and clinical integration including cardiovascular risk prediction and outcome, cost-effectiveness, impact on downstream medical testing, and the technical advances in scanner and software technology that are shaping the future of CAC. Furthermore, this review aims to provide guidance for the appropriate clinical use of CAC. Expert commentary: CAC is a well-established screening test in preventive care that is underused in daily clinical practice. The widespread clinical implementation of CAC will be decided by future technical advances in CT image acquisition, cost-effectiveness, and reimbursement status.
Collapse
Affiliation(s)
- Christian Tesche
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA.,b Department of Cardiology and Intensive Care Medicine , Heart Center Munich-Bogenhausen , Munich , Germany
| | - Taylor M Duguay
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA
| | - U Joseph Schoepf
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA.,c Division of Cardiology, Department of Medicine , Medical University of South Carolina , Charleston , SC , USA
| | - Marly van Assen
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA.,d Center for Medical Imaging North East Netherlands , University Medical Center Groningen, University of Groningen , Groningen , The Netherlands
| | - Carlo N De Cecco
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA
| | - Moritz H Albrecht
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA.,e Department of Diagnostic and Interventional Radiology , University Hospital Frankfurt , Frankfurt , Germany
| | - Akos Varga-Szemes
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA
| | - Richard R Bayer
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA.,c Division of Cardiology, Department of Medicine , Medical University of South Carolina , Charleston , SC , USA
| | - Ullrich Ebersberger
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA.,b Department of Cardiology and Intensive Care Medicine , Heart Center Munich-Bogenhausen , Munich , Germany
| | - John W Nance
- a Division of Cardiovascular Imaging, Department of Radiology and Radiological Science , Medical University of South Carolina , Charleston , SC , USA
| | - Christian Thilo
- f Department of Internal Medicine I - Cardiology , Central Hospital of Augsburg , Augsburg , Germany
| |
Collapse
|
10
|
Vonder M, van der Aalst CM, Vliegenthart R, van Ooijen PMA, Kuijpers D, Gratama JW, de Koning HJ, Oudkerk M. Coronary Artery Calcium Imaging in the ROBINSCA Trial: Rationale, Design, and Technical Background. Acad Radiol 2018; 25:118-128. [PMID: 28843465 DOI: 10.1016/j.acra.2017.07.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/18/2017] [Accepted: 07/20/2017] [Indexed: 01/20/2023]
Abstract
RATIONALE AND OBJECTIVES To describe the rationale, design, and technical background of coronary artery calcium (CAC) imaging in the large-scale population-based cardiovascular disease screening trial (Risk Or Benefit IN Screening for CArdiovascular Diseases [ROBINSCA]). MATERIALS AND METHODS First, literature search was performed to review the logistics, setup, and settings of previously performed CAC imaging studies, and current clinical CAC imaging protocols of participating centers in the ROBINSCA trial were evaluated. A second literature search was performed to evaluate the impact of computed tomography parameter settings on CAC score. RESULTS Based on literature reviews and experts opinion an imaging protocol accompanied by data management protocol was created for ROBINSCA. The imaging protocol should consist of a fixed tube voltage, individually tailored tube current setting, mid-diastolic electrocardiography-triggering, fixed field-of-view, fixed reconstruction kernel, fixed slice thickness, overlapping reconstruction and without iterative reconstruction. The analysis of scans is performed with one type and version of CAC scoring software, by two dedicated and experienced researchers. The data management protocol describes the organization of data handling between the coordinating center, participating centers, and core analysis center. CONCLUSION In this paper we describe the rationale and technical considerations to be taken in developing CAC imaging protocol, and we present a detailed protocol that can be implemented for CAC screening purposes.
Collapse
Affiliation(s)
- Marleen Vonder
- University of Groningen, University Medical Center Groningen, Center for Medical Imaging North-East Netherlands (CMI-NEN), Groningen, The Netherlands
| | - Carlijn M van der Aalst
- Erasmus MC-University Medical Centre, Department of Public Health, Rotterdam, The Netherlands
| | - Rozemarijn Vliegenthart
- University of Groningen, University Medical Center Groningen, Center for Medical Imaging North-East Netherlands (CMI-NEN), Groningen, The Netherlands
| | - Peter M A van Ooijen
- University of Groningen, University Medical Center Groningen, Center for Medical Imaging North-East Netherlands (CMI-NEN), Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Radiology, Groningen, The Netherlands
| | - Dirkjan Kuijpers
- University of Groningen, University Medical Center Groningen, Center for Medical Imaging North-East Netherlands (CMI-NEN), Groningen, The Netherlands; Department of Radiology, Haaglanden Medical Center Bronovo, The Hague, The Netherlands
| | - Jan Willem Gratama
- University of Groningen, University Medical Center Groningen, Center for Medical Imaging North-East Netherlands (CMI-NEN), Groningen, The Netherlands; Department of Radiology, Gelre Hospital, Apeldoorn, The Netherlands
| | - Harry J de Koning
- Erasmus MC-University Medical Centre, Department of Public Health, Rotterdam, The Netherlands
| | - Matthijs Oudkerk
- University of Groningen, University Medical Center Groningen, Center for Medical Imaging North-East Netherlands (CMI-NEN), Groningen, The Netherlands.
| |
Collapse
|
11
|
Iterative beam-hardening correction with advanced modeled iterative reconstruction in low voltage CT coronary calcium scoring with tin filtration: Impact on coronary artery calcium quantification and image quality. J Cardiovasc Comput Tomogr 2017; 11:354-359. [DOI: 10.1016/j.jcct.2017.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 07/06/2017] [Accepted: 07/23/2017] [Indexed: 11/23/2022]
|
12
|
Computed tomography is important in appropriately diagnosing patients with third-degree atrioventricular block and second-degree atrioventricular block but not Wenckebach type. Int J Cardiol 2017; 228:700-706. [DOI: 10.1016/j.ijcard.2016.11.187] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/06/2016] [Indexed: 11/21/2022]
|
13
|
Correction Factors for CT Coronary Artery Calcium Scoring Using Advanced Modeled Iterative Reconstruction Instead of Filtered Back Projection. Acad Radiol 2016; 23:1480-1489. [PMID: 27614365 DOI: 10.1016/j.acra.2016.07.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/16/2016] [Accepted: 07/19/2016] [Indexed: 11/19/2022]
Abstract
RATIONALE AND OBJECTIVES Iterative reconstruction (IR) computed tomography (CT) techniques allow for radiation dose reduction while maintaining image quality. However, CT coronary artery calcium (CAC) scores may be influenced by certain IR algorithms. The aim of our study is to identify suitable correction factors to ensure consistency between IR and filtered back projection (FBP)-based CAC scoring. MATERIAL AND METHODS A phantom study was performed to derive suitable correction factors for CAC scores and volume (VOL) values with advanced modeled iterative reconstruction (or ADMIRE) strength level 3 (ADM3) and 5 (ADM5) vs FBP. CT data from 40 patients were retrospectively analyzed, and CAC score and VOL values were obtained following reconstruction with FBP, ADM3, and ADM5. Linear regression analysis was performed to obtain correction factors. Results with and without application of the correction factors were compared. Inter-reader agreement for risk class stratification was analyzed. RESULTS Phantom experiments determined a correction factor of 1.14 for ADM3 and 1.25 for ADM5. FBP-based CAC scores (897 ± 1413) were significantly higher than uncorrected scores with ADM3 (746 ± 1184, P ≤ .001) and ADM5 (640 ± 1036, P ≤ .001). After application of correction factors, no significant differences were found for CAC scores based on FBP (897 ± 1413) and ADM3 (853 ± 1353, P = .07). The inter-reader agreement for risk stratification was excellent (k = 0.91). CONCLUSION ADM3 can be applied to CAC scoring with use of a correction factor. When applying a correction factor of 1.14, excellent agreement with standard FBP for both CAC score and VOL can be achieved.
Collapse
|
14
|
den Harder AM, Wolterink JM, Willemink MJ, Schilham AM, de Jong PA, Budde RP, Nathoe HM, Išgum I, Leiner T. Submillisievert coronary calcium quantification using model-based iterative reconstruction: A within-patient analysis. Eur J Radiol 2016; 85:2152-2159. [DOI: 10.1016/j.ejrad.2016.09.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 09/26/2016] [Accepted: 09/29/2016] [Indexed: 11/16/2022]
|
15
|
Choi AD, Leifer ES, Yu J, Shanbhag SM, Bronson K, Arai AE, Chen MY. Prospective evaluation of the influence of iterative reconstruction on the reproducibility of coronary calcium quantification in reduced radiation dose 320 detector row CT. J Cardiovasc Comput Tomogr 2016; 10:359-63. [PMID: 27591767 PMCID: PMC7458582 DOI: 10.1016/j.jcct.2016.07.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 07/13/2016] [Accepted: 07/16/2016] [Indexed: 01/07/2023]
Abstract
BACKGROUND Coronary artery calcium (CAC) predicts coronary heart disease events and is important for individualized cardiac risk assessment. This report assesses the interscan variability of CT for coronary calcium quantification using image acquisition with standard and reduced radiation dose protocols and whether the use of reduced radiation dose acquisition with iterative reconstruction (IR; "reduced-dose/IR ") allows for similar image quality and reproducibility when compared to standard radiation dose acquisition with filtered back projection (FBP; "standard-dose/FBP") on 320-detector row computed tomography (320-CT). METHODS 200 consecutive patients (60 ± 9 years, 59% male) prospectively underwent two standard- and two reduced-dose acquisitions (800 total scans, 1600 reconstructions) using 320 slice CT and 120 kV tube voltage. Automated tube current modulation was used and for reduced-dose scans, prescribed tube current was lowered by 70%. Image noise and Agatston scores were determined and compared. RESULTS Regarding stratification by Agatston score categories (0, 1-10, 11-100, 101-400, >400), reduced-dose/IR versus standard-dose/FBP had excellent agreement at 89% (95% CI: 86-92%) with kappa 0.86 (95% CI: 0.81-0.90). Standard-dose/FBP rescan agreement was 93% (95% CI: 89-96%) with kappa = 0.91 (95% CI: 0.86-0.95) while reduced-dose/IR rescan agreement was similar at 91% (95% CI: 87-94%) with kappa 0.88 (95% CI: 0.83-0.93). Image noise was significantly higher but clinically acceptable for reduced-dose/IR (18 Hounsfield Unit [HU] mean) compared to standard-dose/FBP (16 HU; p < 0.0001). Median radiation exposure was 74% lower for reduced- (0.37 mSv) versus standard-dose (1.4 mSv) acquisitions. CONCLUSION Rescan agreement was excellent for reduced-dose image acquisition with iterative reconstruction and standard-dose acquisition with filtered back projection for the quantification of coronary calcium by CT. These methods make it possible to reduce radiation exposure by 74%. CLINICAL TRIAL REGISTRATION URL: https://clinicaltrials.gov/ct2/show/NCT01621594. UNIQUE IDENTIFIER NCT01621594.
Collapse
Affiliation(s)
- Andrew D Choi
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA; Division of Cardiology and Department of Radiology, The George Washington University School of Medicine, Washington, DC, USA
| | - Eric S Leifer
- Office of Biostatistics Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jeannie Yu
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Sujata M Shanbhag
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Kathie Bronson
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Andrew E Arai
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Marcus Y Chen
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
16
|
Schaafs LA, Lenk J, Hamm B, Niehues SM. Reducing the dose of CT of the paranasal sinuses: potential of an iterative reconstruction algorithm. Dentomaxillofac Radiol 2016; 45:20160127. [PMID: 27351346 DOI: 10.1259/dmfr.20160127] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To evaluate the feasibility and image quality of low-dose CT of the paranasal sinuses using iterative reconstruction with adaptive-iterative dose reduction in three dimensions (AIDR 3D) in comparison with conventional image protocols of older scanner generations. METHODS Sinus CT scans of 136 patients were assessed retrospectively. Patients underwent CT either with low-dose settings (Protocol A: 80 kV, 30 mA s; Protocol B: 120 kV, 15 mA s or C: 80 kV, 90 mA s) reconstructed using AIDR 3D (Protocols A and B) or filtered back projection (FBP) (Protocol C) or with standard dose (Protocol D: 120 kV, 80 mA s) and FBP. Image quality was assessed in consensus by two blinded readers scoring the diagnostic image quality (from 1 = excellent to 5 = non-diagnostic) and conspicuity of important anatomic landmarks (from 0 = not visible to 2 = completely visible; maximum score of 16 points) as well as osseous structures (maximum score of 12 points). Dose-length product, effective dose (ED), CT dose index and scan length were retrieved for each scan and compared. RESULTS Mean ED could be lowered by 82% when using Protocol A. The best image quality was found using Protocol B (mean score = 2.1 ± 0.51). Conspicuity of relevant anatomic landmarks was best with Protocol A (mean score = 11.97 ± 1.88). Protocol B provided the highest conspicuity of osseous structures (mean score = 8.27 ± 1.58). Image noise was highest in images obtained using Protocol A. CONCLUSIONS AIDR 3D allows a significant dose reduction while maintaining a good diagnostic image quality and conspicuity of relevant anatomic structures.
Collapse
Affiliation(s)
- Lars-Arne Schaafs
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Julian Lenk
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Stefan Markus Niehues
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
17
|
Diagnostic Phase of Calcium Scoring Scan Applied as the Center of Acquisition Window of Coronary Computed Tomography Angiography Improves Image Quality in Minimal Acquisition Window Scan (Target CTA Mode) Using the Second Generation 320-Row CT. ScientificWorldJournal 2016; 2016:1017851. [PMID: 26977449 PMCID: PMC4764755 DOI: 10.1155/2016/1017851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 01/04/2016] [Accepted: 01/13/2016] [Indexed: 11/30/2022] Open
Abstract
Objective. To compare the image quality of coronary computed tomography angiography (CCTA) acquired under two conditions: 75% fixed as the acquisition window center (Group 75%) and the diagnostic phase for calcium scoring scan as the center (CS; Group CS). Methods. 320-row cardiac CT with a minimal acquisition window (scanned using “Target CTA” mode) was performed on 81 patients. In Group 75% (n = 40), CS was obtained and reconstructed at 75% and the center of the CCTA acquisition window was set at 75%. In Group CS (n = 41), CS was obtained at 75% and the diagnostic phase showing minimal artifacts was applied as the center of the CCTA acquisition window. Image quality was evaluated using a four-point scale (4-excellent) and the mean scores were compared between groups. Results. The CCTA scan diagnostic phase occurred significantly earlier in CS (75.7 ± 3.2% vs. 73.6 ± 4.5% for Groups 75% and CS, resp., p = 0.013). The mean Group CS image quality score (3.58 ± 0.63) was also higher than that for Group 75% (3.19 ± 0.66, p < 0.0001). Conclusions. The image quality of CCTA in Target CTA mode was significantly better when the center of acquisition window is adjusted using CS.
Collapse
|
18
|
Szilveszter B, Elzomor H, Károlyi M, Kolossváry M, Raaijmakers R, Benke K, Celeng C, Bartykowszki A, Bagyura Z, Lux Á, Merkely B, Maurovich-Horvat P. The effect of iterative model reconstruction on coronary artery calcium quantification. Int J Cardiovasc Imaging 2015; 32:153-60. [DOI: 10.1007/s10554-015-0740-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 08/11/2015] [Indexed: 01/07/2023]
|