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Li J, Wei WF, Song LN, Mei XY, Yuan XS, He JB, Jiang LZ, Li HY, Wu HL, Chen JP. Double low-dose computed tomography (CT) angiography of craniocervical arteries using a test bolus of diluted contrast medium and a personalized contrast protocol. Clin Radiol 2024:S0009-9260(24)00407-0. [PMID: 39198109 DOI: 10.1016/j.crad.2024.07.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 07/24/2024] [Accepted: 07/29/2024] [Indexed: 09/01/2024]
Abstract
AIM To prospectively assess the value of a test bolus of diluted contrast medium (CM) combined with a personalized contrast protocol in craniocervical computed tomography angiography (cc-CTA) with low radiation and CM doses. MATERIALS AND METHODS Eighty-six consecutive subjects were divided into two groups at random (43 in each one): group A: 100/Sn140 kVp, filtered back-projection reconstruction, iopromide (370 mgI/ml) 50 ml; group B: 80/Sn140 kVp, iterative reconstruction, iodixanol (270 mgI/ml). In group B, the test bolus contained 27 ml of diluted CM, a personalized protocol with low-concentration CM was used for angiography, and the test bolus injection duration in angiography remained the same. Artery values over 200 Hounsfield units were considered significant. RESULTS Image quality for all cases was found to be diagnostic. No significant differences were found in the arterial densities of the ascending aorta or basilar artery between the groups. The values of the common carotid artery, internal carotid artery, and middle cerebral artery in group B were significantly lower. The effective dose and average iodine uptake were significantly lower in group B. CONCLUSION With double-low-dose cc-CTA, test bolus scanning based on diluted CM combined with a personalized contrast protocol can yield diagnostic-quality images and significantly reduce the radiation and CM doses.
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Affiliation(s)
- J Li
- Department of Radiology, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China
| | - W-Feng Wei
- Department of Neurosurgery, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China
| | - L-N Song
- Medical Record Department, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China
| | - X-Y Mei
- Department of Radiology, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China
| | - X-S Yuan
- Department of Neurosurgery, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China
| | - J-B He
- Department of Radiology, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China
| | - L-Z Jiang
- Department of Radiology, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China
| | - H-Y Li
- Department of Radiology, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China.
| | - H-Lin Wu
- Department of Radiology, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China.
| | - J-P Chen
- Department of Radiology, Wujin Hospital Affiliated to Jiangsu University, Wujin Clinical College of Xuzhou Medical University, Changzhou 213002, Jiangsu, China.
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Zhou X, Cui M, Liu Y, Wu Y, Hu D, Zhai D, Qin M, Shen J, Ju S, Fan G, Cai W. Low Dose Iodinated Contrast Material and Radiation for Virtual Monochromatic Imaging in Craniocervical Dual-Layer Spectral Detector Computed Tomography Angiography: A Prospective and Randomized Study. Acad Radiol 2024; 31:2501-2510. [PMID: 38135625 DOI: 10.1016/j.acra.2023.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 12/01/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023]
Abstract
RATIONALE AND OBJECTIVES To investigate the feasibility of virtual monochromatic imaging (VMI) of dual-layer spectral detector computed tomography (SDCT) to reduce iodinated contrast material (CM) and radiation dose in craniocervical computed tomography angiography (CTA). MATERIALS AND METHODS A total of 280 consecutively selected patients performed craniocervical CTA with SDCT were prospectively selected and randomly divided into four groups (A, DoseRight index (DRI) 31, iopromide 370mgI/mL, volume 0.8 mL/kg; B, DRI 26, iopromide 370mgI/mL, volume 0.4 mL/kg; C, DRI 26, ioversol 320mgI/mL, volume 0.4 mL/kg; D, DRI 26, iohexol 300mgI/mL, volume 0.4 mL/kg). 50-70 kiloelectron volts (keV) VMIs in group B were reconstructed and compared to group A to select the optimal keV. Then, the optimal keV in groups B, C and D was reconstructed and compared. Objective image quality, including vascular attenuation, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), was evaluated. Subjective image quality was assessed using a 5-point Likert scale. In addition, the effective dose (ED), iodine load and iodine delivery rate (IDR) were compared between groups A and D. RESULTS 55 keV VMI was the optimal VMI in group B. The objective and subjective image quality of 55 keV VMI in group B were equal to or better than those of the CI in group A. The SNR, CNR and subjective image quality in group D were similar to those in group B (P > 0.05). The ED, iodine load and IDR of group D were reduced by 44%, 59% and 19%, respectively, when compared to those of group A. CONCLUSION Low dose iodinated CM and radiation for 55 keV VMI in craniocervical CTA using SDCT could still provide equivalent or better image quality than the conventional scanning protocol.
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Affiliation(s)
- Xiuzhi Zhou
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Manman Cui
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Yan Liu
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Yuanyuan Wu
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Dongliang Hu
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Duchang Zhai
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Mingyu Qin
- Suzhou Medical College of Soochow University, Suzhou, 215026, Jiangsu, China (M.Q.)
| | - Junkang Shen
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Shenghong Ju
- Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, 210009, Jiangsu, China (S.J.)
| | - Guohua Fan
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.)
| | - Wu Cai
- Department of Radiology, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Gusu, Suzhou, 215004, Jiangsu, China (X.Z., M.C., Y.L., Y.W., D.H., D.Z., J.S., G.F., W.C.).
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Wu H, Wang J, Zhou M, Wang Y, Cui C, Zhou C, Chen X, Wang Z. Application of bolus tracking: The effect of ROI positions on the images quality of cervicocerebral CT angiography. Heliyon 2024; 10:e29260. [PMID: 38617933 PMCID: PMC11015132 DOI: 10.1016/j.heliyon.2024.e29260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 03/28/2024] [Accepted: 04/03/2024] [Indexed: 04/16/2024] Open
Abstract
Background Cervicocerebral CT angiography (CTA) using the bolus tracking technique has been widely used for the assessment of cerebrovascular diseases. Regions of interest (ROI) can be placed in the descending aorta, ascending aorta, and the aortic arch. However, no study has compared the arteries and veins display when when the region of interest (ROI) is placed at different sites. In this study, we showed the impact of ROI positions on the image quality of cervicocerebral CTA. Methods Two hundred and seventy patients who underwent cervicocerebral CTA with bolus tracking technique were randomly divided into three groups based on the position of the ROI placement: ascending aorta (Group 1, n = 90), aortic arch (Group 2, n = 90), and descending aorta (Group 3, n = 90). The scanning parameters and contrast agent injection protocols were consistent across all groups. Three observers independently assessed the objective image quality, while two observers jointly assessed the subjective image quality using a grade scale: poor (grade 1), average (grade 2), good (grade 3), and excellent (grade 4). The differences in intravascular CT values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), AVCR (arterial venous contrast ratio), and subjective image quality scores were compared among the three groups. Results The CT values of the intracranial veins (superior sagittal sinus, ethmoid sinus and great cerebral vein) in group 1 were significantly lower than those in group 3 (p < 0.001). However, no significant differences were observed in CT values, SNR and CNR in the internal carotid artery and middle cerebral artery among the three groups. The proportion of images with grade 4 was significantly higher in group 1 than group 2 and 3 (41.1% vs 15.6% and 13.3%, p < 0.001). The proportion of images with grade 1 was significantly lower in group 1 than group 2 and 3 (1.1% vs 6.6% and 17.8%, p < 0.001). Conclusion The ROI positions for cervicocerebral CTA did not affect the arterial image quality, but venous structures imaging was affected when the ROI was placed in the ascending aorta.
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Affiliation(s)
- Huiming Wu
- Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China
| | - Jianhua Wang
- Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China
| | - Maodong Zhou
- Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China
| | - Yajie Wang
- Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China
| | - Can Cui
- Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China
| | - Changsheng Zhou
- Department of Radiology, Jinling Hospital Nanjing University, 305 Zhongshan East road, Nanjing, 210029, China
| | - Xiao Chen
- Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China
| | - Zhongqiu Wang
- Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China
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Yuan Z, Liu T, Zhang B, Wu J, He Y, Chen T, Zhang Z, Li C, Liu Y. Comparison of selected photon shield and organ-based tube current modulation for radiation dose reduction in head computed tomography: A phantom study. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2023:XST230018. [PMID: 37092211 DOI: 10.3233/xst-230018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
OBJECTIVE The aim of this study is to investigate the radiation dose and image quality of head CT using SPS and OBTCM techniques. METHODS Three anthropomorphic head phantoms (1-yr-old, 5-yr-old, and adult) were used. Images were acquired using four modes (Default protocol, OBTCM, SPS, and SPS+OBTCM). Absorbed dose to the lens, anterior brain (brain_A), and posterior brain (brain_P) was measured and compared. Image noise and CNR were assessed in the selected regions of interest (ROIs). RESULTS Compared with that in the Default protocol, the absorbed dose to the lens reduced by up to 28.33%,71.38%, and 71.12% in OBTCM, SPS, and SPS+OBTCM, respectively. The noise level in OBTCM slightly (≤1.45HU) increased than that in Default protocol, and the SPS or SPS+OBTCM mode resulted in a quantitatively small increase (≤2.58HU) in three phantoms. There was no significant difference in CNR of different phantoms under varies scanning modes (p > 0.05). CONCLUSIONS During head CT examinations, the SPS mode can reduce the radiation dose while maintaining image quality. SPS+OBTCM couldn't further effectively reduce the absorbed dose to the lens for 1-yr and 5-yr-old phantoms. Thus, SPS mode in pediatric and SPS+OBTCM mode in adult are better than other modes, and should be used in clinical practice.
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Affiliation(s)
- Zilong Yuan
- Department of Radiology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tao Liu
- Department of Radiology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Biao Zhang
- Department of Radiology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | | | - Yaoyao He
- Department of Radiology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tiao Chen
- Department of Radiology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhaoxi Zhang
- Department of Radiology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Cuiling Li
- Department of Radiological Health, Wuhan Prevention and Treatment for Occupational Disease, Wuhan, China
| | - Yulin Liu
- Department of Radiology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Impact of increasing levels of adaptive statistical iterative reconstruction on image quality in oil-based postmortem CT angiography in coronary arteries. Int J Legal Med 2021; 135:1869-1878. [PMID: 33629138 PMCID: PMC8354936 DOI: 10.1007/s00414-021-02530-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 02/03/2021] [Indexed: 01/03/2023]
Abstract
Introduction Postmortem multi-detector computed tomography (PMCT) has become an important part in forensic imaging. Modern reconstruction techniques such as iterative reconstruction (IR) are frequently used in postmortem CT angiography (PMCTA). The image quality of PMCTA depends on the strength of IR. For this purpose, we aimed to investigate the impact of different advanced IR levels on the objective and subjective PMCTA image quality. Material and methods We retrospectively analyzed the coronary arteries of 27 human cadavers undergoing whole-body postmortem CT angiography between July 2017 and March 2018 in a single center. Iterative reconstructions of the coronary arteries were processed in five different level settings (0%; 30%; 50%; 70%; 100%) by using an adaptive statistical IR method. We evaluated the objective (contrast-to-noise ratio (CNR)) and subjective image quality in several anatomical locations. Results Our results demonstrate that the increasing levels of an IR technique have relevant impact on the image quality in PMCTA scans in forensic postmortem examinations. Higher levels of IR have led to a significant reduction of image noise and therefore to a significant improvement of objective image quality (+ 70%). However, subjective image quality is inferior at higher levels of IR due to plasticized image appearance. Conclusion Objective image quality in PMCTA progressively improves with increasing level of IR with the best CNR at the highest IR level. However, subjective image quality is best at low to medium levels of IR. To obtain a “classic” image appearance with optimal image quality, PMCTAs should be reconstructed at medium levels of IR.
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Sun Y, Hua Y, Wang M, Mao D, Jin X, Li C, Shi K, Xu J. Evaluation of a High Concentrated Contrast Media Injection Protocol in Combination with Low Tube Current for Dose Reduction in Coronary Computed Tomography Angiography: A Randomized, Two-center Prospective Study. Acad Radiol 2017; 24:1482-1490. [PMID: 28800951 DOI: 10.1016/j.acra.2017.07.001] [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: 05/02/2017] [Revised: 07/03/2017] [Accepted: 07/05/2017] [Indexed: 11/25/2022]
Abstract
RATIONALE AND OBJECTIVES The study aimed to prospectively evaluate the radiation dose reduction potential and image quality (IQ) of a high-concentration contrast media (HCCM) injection protocol in combination with a low tube current (mAs) in coronary computed tomography angiography. MATERIALS AND METHODS Eighty-one consecutive patients (mean age: 62 years; 34 females; body mass index: 18-31) were included and randomized-assigned into two groups. All computed tomography (CT) examinations were performed in two groups with the same tube voltage (100 kV), flow rate of contrast medium (5.0 mL/s), and iodine dose (22.8 g). An automatic mAs and low concentration contrast medium (300 mgI/mL) were used in group A, whereas effective mAs was reduced by a factor 0.6 along with HCCM (400 mgI/mL) in group B. Radiation dose was assessed (CT dose index [CTDIvol] and dose length product), and vessel-based objective IQ for various regions of interest (enhancement, noise, signal-to-noise ratio, and contrast-to-noise ratio), subjective IQ, noise, and motion artifacts were analyzed overall and vessel-based with a 5-point Likert scale. RESULTS The CT attenuation of coronary arteries and image noise in group B were significantly higher than those in group A (ranges: 507.5-548.1 Hounsfield units vs 407.5-444.5 Hounsfield units; and 20.3 ± 8.6 vs 17.7 ± 8.0) (P ≤ 0.0166). There was no significant difference between the two groups in signal-to-noise ratio, contrast-to-noise ratio, and subjective IQ of coronary arteries (29.4-31.7, 30.0-37.0, and medium score of 5 in group A vs 29.4-32.4, 27.7-36.3, and medium score of 5 in group B, respectively, P ≥ 0.1859). Both mean CTDIvol and dose length product in group B were 58% of those of group A. CONCLUSIONS HCCM combined with low tube current allows dose reduction in coronary computed tomography angiography and does not compromise IQ.
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Cai W, Hu C, Hu S, Wang X, Gong J, Zhang W, Shi D, Cheng B. Feasibility study of iterative model reconstruction combined with low tube voltage, low iodine load, and low iodine delivery rate in craniocervical CT angiography. Clin Radiol 2017; 73:217.e1-217.e6. [PMID: 29066028 DOI: 10.1016/j.crad.2017.09.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 05/18/2017] [Accepted: 09/20/2017] [Indexed: 12/11/2022]
Abstract
AIM To investigate the feasibility of iterative model reconstruction (IMR) combined with low tube voltage, low iodine load, and low iodine deliver rate in craniocervical computed tomography angiography (CTA). MATERIALS AND METHODS Sixty patients were randomly divided into two groups (n=30 for each): group A: 120 kVp, 50 ml of iopromide at a flow rate of 5 ml/s; filtered back projection (FBP) reconstruction; group B: 80 kVp, 30 ml of iohexol at 4.5 ml/s; hybrid iterative reconstruction (HIR) for group B1 and IMR for group B2. CT attenuation values, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective image quality, effective dose (ED), iodine load, and iodine delivery rate (IDR) were compared. RESULTS CT attenuation values of the arteries were higher in groups B1 and B2 than group A. The SNR and CNR were higher, while image noise was lower, for group B2 compared with groups B1 and A. The best subjective image quality was obtained with group B2. ED, iodine load, and IDR reduction of 69.6%, 51.4%, 27%, respectively, was obtained in group B compared with group A. CONCLUSION IMR combined with 80 kVp and 30 ml of iohexol at a flow rate of 4.5 ml/s for craniocervical CTA can reduce ED, iodine load, and IDR, while improving image quality.
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Affiliation(s)
- W Cai
- Department of Radiology, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China; Department of Radiology, Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - C Hu
- Department of Radiology, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
| | - S Hu
- Department of Radiology, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - X Wang
- Department of Radiology, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - J Gong
- Department of Radiology, Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - W Zhang
- Department of Radiology, Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - D Shi
- Department of Radiology, Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - B Cheng
- Department of Radiology, West China Second University Hospital of Sichuan University, Chengdu, Sichuan, China
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Evaluation of a high iodine delivery rate in combination with low tube current for dose reduction in pulmonary computed tomography angiography. J Thorac Imaging 2015; 29:293-7. [PMID: 25100138 DOI: 10.1097/rti.0000000000000099] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The present study evaluates the combination of a high iodine delivery rate with a low tube current-time product for pulmonary computed tomography angiography (CTA). MATERIALS AND METHODS One-hundred nineteen consecutive patients undergoing pulmonary CTA for suspected pulmonary embolism were included and imaged on a 128-row computed tomography scanner at 100 kVp using highly concentrated contrast material (85 mL Iomeprol; 400 mg iodine/mL). The protocol entailed a flow rate of 5 mL/s and 90 mAs for group A, 3.5 mL/s and 135 mAs for group B, 5 mL/s and 135 mAs for group C, and 3.5 mL/s and 90 mAs for group D. Signal-to-noise ratio and contrast-to-noise ratio (CNR) were determined for the pulmonary artery. Subjective image quality (IQ) was rated on a 5-point scale (1=nondiagnostic IQ to 5=excellent IQ). RESULTS CNR did not differ significantly between groups A (43.7±27.7), B (34.5±17.9), and C (38.9±13.8), as well as between groups B and D (29.9±11.2). CNR was higher in groups A and C than in group D (P<0.02). Subjective IQ was higher in group A than in groups B and D (P<0.05). Subjective IQ was significantly higher in group A compared with group D (P=0.026) and in group C compared with group D (P=0.007). CONCLUSIONS A high iodine delivery rate permits dose reduction in pulmonary CTA and can be recommended in patients with suspected pulmonary embolism.
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Boos J, Kröpil P, Klee D, Heusch P, Schimmöller L, Schaper J, Antoch G, Lanzman RS. Evaluation of the impact of organ-specific dose reduction on image quality in pediatric chest computed tomography. Pediatr Radiol 2014; 44:1065-9. [PMID: 25022489 DOI: 10.1007/s00247-014-2950-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 02/18/2014] [Accepted: 02/26/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Organ-specific dose reduction significantly reduces the radiation exposure of radiosensitive organs. OBJECTIVE The purpose of this study was to assess the impact of a novel organ-specific dose reduction algorithm on image quality of pediatric chest CT. MATERIALS AND METHODS We included 28 children (mean age 10.9 ± 4.8 years, range 3-18 years) who had contrast-enhanced chest CT on a 128-row scanner. CT was performed at 100 kV using automated tube current modulation and a novel organ-specific dose-reduction algorithm (XCare™; Siemens, Forchheim, Germany). Seven children had a previous chest CT performed on a 64-row scanner at 100 kV without organ-specific dose reduction. Subjective image quality was assessed using a five-point scale (1-not diagnostic; 5-excellent). Contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were assessed in the descending aorta. RESULTS Overall mean subjective image quality was 4.1 ± 0.6. In the subgroup of the seven children examined both with and without organ-specific dose reduction, subjective image quality was comparable (score 4.4 ± 0.5 with organ-specific dose reduction vs. 4.4 ± 0.7 without it; P > 0.05). There was no significant difference in mean signal-to-noise ratio and contrast-to-noise ratio with organ-specific dose reduction (38.3 ± 10.1 and 28.5 ± 8.7, respectively) and without the reduction (35.5 ± 8.5 and 26.5 ± 7.8, respectively) (P > 0.05). Volume computed tomography dose index (CTDIvol) and size-specific dose estimates did not differ significantly between acquisitions with the organ-specific dose reduction (1.7 ± 0.8 mGy) and without the reduction (1.7 ± 0.8 mGy) (P > 0.05). CONCLUSION Organ-specific dose reduction does not have an impact on image quality of pediatric chest CT and can therefore be used in clinical practice to reduce radiation dose of radiosensitive organs such as breast and thyroid gland.
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Affiliation(s)
- Johannes Boos
- Department of Diagnostic and Interventional Radiology, University Dusseldorf, Medical Faculty, D-40225, Dusseldorf, Germany
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Schimmöller L, Lanzman R, Dietrich S, Boos J, Heusch P, Miese F, Antoch G, Kröpil P. Evaluation of automated attenuation-based tube potential selection in combination with organ-specific dose reduction for contrast-enhanced chest CT examinations. Clin Radiol 2014; 69:721-6. [DOI: 10.1016/j.crad.2014.02.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 02/10/2014] [Accepted: 02/24/2014] [Indexed: 12/28/2022]
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