1
|
Li Y, Liu X, Zhuang XH, Wang MJ, Song XF. Assessment of low-dose paranasal sinus CT imaging using a new deep learning image reconstruction technique in children compared to adaptive statistical iterative reconstruction V (ASiR-V). BMC Med Imaging 2022; 22:106. [PMID: 35658908 PMCID: PMC9164403 DOI: 10.1186/s12880-022-00834-1] [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: 12/21/2021] [Accepted: 05/27/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose To compare the effects of deep learning image reconstruction (DLIR) and adaptive statistical iterative reconstruction V (ASiR-V) on image quality in low-dose computed tomography (CT) of paranasal sinuses in children. Methods Low-dose CT scans of the paranasal sinuses in 25 pediatric patients were retrospectively evaluated. The raw data were reconstructed with three levels of DLIR (high, H; medium, M; and low, L), filtered back projection (FBP), and ASiR-V (30% and 50%). Image noise was measured in both soft tissue and bone windows, and the signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of the images were calculated. Subjective image quality at the ethmoid sinus and nasal cavity levels of the six groups of reconstructed images was assessed by two doctors using a five-point Likert scale in a double-blind manner. Results The patients’ mean dose-length product and effective dose were 36.65 ± 2.44 mGy·cm and 0.17 ± 0.03 mSv, respectively. (1) Objective evaluation: 1. Soft tissue window: The difference among groups in each parameter was significant (P < 0.05). Pairwise comparisons showed that the H group’ s parameters were significantly better (P < 0.05) than those of the 50% post-ASiR-V group. 2. Bone window: No significant between-group differences were found in the noise of the petrous portion of the temporal bone or its SNR or in the noise of the pterygoid processes of the sphenoids or their SNRs (P > 0.05). Significant differences were observed in the background noise and CNR (P < 0.05). As the DLIR intensity increased, image noise decreased and the CNR improved. The H group exhibited the best image quality. (2) Subjective evaluation: Scores for images of the ethmoid sinuses were not significantly different among groups (P > 0.05). Scores for images of the nasal cavity were significantly different among groups (P < 0.05) and were ranked in descending order as follows: H, M, L, 50% post-ASiR-V, 30% post-ASiR-V, and FBP. Conclusion DLIR was superior to FBP and post-ASiR-V in low-dose CT scans of pediatric paranasal sinuses. At high intensity (H), DLIR provided the best reconstruction effects.
Collapse
|
2
|
Tan D, Mohamad NA, Wong YH, Yeong CH, Cheah PL, Sulaiman N, Abdullah BJJ, Fabell MK, Lim KS. Experimental assessment on feasibility of computed tomography-based thermometry for radiofrequency ablation on tissue equivalent polyacrylamide phantom. Int J Hyperthermia 2019; 36:554-561. [DOI: 10.1080/02656736.2019.1610800] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Affiliation(s)
- Daryl Tan
- School of Medicine, Faculty of Health and Medical Sciences, Taylor’s University, Subang Jaya, Selangor, Malaysia
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor’s University, Subang Jaya, Selangor, Malaysia
| | - Nurul Ashikin Mohamad
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yin How Wong
- School of Medicine, Faculty of Health and Medical Sciences, Taylor’s University, Subang Jaya, Selangor, Malaysia
| | - Chai Hong Yeong
- School of Medicine, Faculty of Health and Medical Sciences, Taylor’s University, Subang Jaya, Selangor, Malaysia
| | - Peng Loon Cheah
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Norshazriman Sulaiman
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Basri Johan Jeet Abdullah
- School of Medicine, Faculty of Health and Medical Sciences, Taylor’s University, Subang Jaya, Selangor, Malaysia
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohd Kamil Fabell
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kok Sing Lim
- Photonics Research Centre, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
3
|
Tan SK, Yeong CH, Raja Aman RRA, Ng KH, Abdul Aziz YF, Chee KH, Sun Z. Low tube voltage prospectively ECG-triggered coronary CT angiography: a systematic review of image quality and radiation dose. Br J Radiol 2018; 91:20170874. [PMID: 29493261 DOI: 10.1259/bjr.20170874] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE This study aimed (1) to perform a systematic review on scanning parameters and contrast medium (CM) reduction methods used in prospectively electrocardiography (ECG-triggered low tube voltage coronary CT angiography (CCTA), (2) to compare the achievable dose reduction and image quality and (3) to propose appropriate scanning techniques and CM administration methods. METHODS A systematic search was performed in PubMed, the Cochrane library, CINAHL, Web of Science, ScienceDirect and Scopus, where 20 studies were selected for analysis of scanning parameters and CM reduction methods. RESULTS The mean effective dose (HE) ranged from 0.31 to 2.75 mSv at 80 kVp, 0.69 to 6.29 mSv at 100 kVp and 1.53 to 10.7 mSv at 120 kVp. Radiation dose reductions of 38 to 83% at 80 kVp and 3 to 80% at 100 kVp could be achieved with preserved image quality. Similar vessel contrast enhancement to 120 kVp could be obtained by applying iodine delivery rate (IDR) of 1.35 to 1.45 g s-1 with total iodine dose (TID) of between 10.9 and 16.2 g at 80 kVp and IDR of 1.08 to 1.70 g s-1 with TID of between 18.9 and 20.9 g at 100 kVp. CONCLUSION This systematic review found that radiation doses could be reduced to a rate of 38 to 83% at 80 kVp, and 3 to 80% at 100 kVp without compromising the image quality. Advances in knowledge: The suggested appropriate scanning parameters and CM reduction methods can be used to help users in achieving diagnostic image quality with reduced radiation dose.
Collapse
Affiliation(s)
- Sock Keow Tan
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | - Chai Hong Yeong
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | | | - Kwan Hoong Ng
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | - Yang Faridah Abdul Aziz
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | - Kok Han Chee
- 1 Department of Biomedical Imaging, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia.,2 Department of Medicine, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | - Zhonghua Sun
- 3 Department of Medical Radiation Sciences, Curtin University , Perth, WA , Australia
| |
Collapse
|
4
|
Wang C, Liao Y, Chen H, Zhen X, Li J, Xu Y, Zhou L. Influence of tube potential on quantitative coronary plaque analyses by low radiation dose computed tomography: a phantom study. Int J Cardiovasc Imaging 2018; 34:1315-1322. [PMID: 29582238 DOI: 10.1007/s10554-018-1344-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/22/2018] [Indexed: 12/18/2022]
Abstract
Previous studies have shown that employing the low dose computed tomography (CT) technique based on low tube potential reduces the radiation dose required for the coronary artery examination protocol. However, low tube potential may adversely influence the CT number of plaque composition. Therefore, we aimed to determine whether quantitative atherosclerotic plaque analysis by a multi-slice, low radiation dose CT protocol using 80 kilovolts (kV) yields results comparable to those of the standard 120 kV protocol. Artificial plaque samples (n = 17) composed of three kinds of plaque were scanned at 120 and 80 kV. Relative low-density and medium-density plaque component volumes obtained by three protocols (80 kV, 60 Hounsfield units [HU] threshold; 120 kV, 60 HU threshold; and 80 kV, 82 HU threshold) were compared. Using the 60 HU threshold, relative volume of the low-density plaque component obtained at 80 kV was lower than that obtained at 120 kV (27 ± 3% vs. 51 ± 5%, P < 0.001), whereas relative volume of the medium-density plaque component obtained at 80 kV was higher than that obtained at 120 kV (73 ± 3% vs. 48 ± 5%, P < 0.001). By contrast, no significant difference in relative volume obtained at 80 kV (82 HU threshold) versus 120 kV (60 HU threshold) was observed for either low-density (52 ± 5% vs. 51 ± 5%) or medium-density (48 ± 5% vs. 48 ± 5%) plaque component. Low tube potential may affect the accuracy of quantitative atherosclerotic plaque analysis. For our phantom test, 82 HU was the optimal threshold for scanning at 80 kV.
Collapse
Affiliation(s)
- Chunhong Wang
- Department of Radiology, Xinyang Central Hospital, Xinyang, 464002, Henan, China
| | - Yuliang Liao
- Department of Biomedical Engineering, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Haibin Chen
- Department of Biomedical Engineering, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Xin Zhen
- Department of Biomedical Engineering, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Jianhong Li
- Department of Radiology, Xinyang Central Hospital, Xinyang, 464002, Henan, China
| | - Yikai Xu
- Department of Medical Imaging Center, Nanfang Hospital, Southern Medical University, No. 1838 Guangzhou Avenue North, Guangzhou, 510515, Guangdong, China.
| | - Linghong Zhou
- Department of Biomedical Engineering, Southern Medical University, Guangzhou, 510515, Guangdong, China.
| |
Collapse
|
5
|
Suntharalingam S, Mikat C, Stenzel E, Erfanian Y, Wetter A, Schlosser T, Forsting M, Nassenstein K. Submillisievert standard-pitch CT pulmonary angiography with ultra-low dose contrast media administration: A comparison to standard CT imaging. PLoS One 2017; 12:e0186694. [PMID: 29045463 PMCID: PMC5646863 DOI: 10.1371/journal.pone.0186694] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 10/05/2017] [Indexed: 11/29/2022] Open
Abstract
Objectives To evaluate the image quality and radiation dose of submillisievert standard-pitch CT pulmonary angiography (CTPA) with ultra-low dose contrast media administration in comparison to standard CTPA. Materials and methods Hundred patients (56 females, 44 males, mean age 69.6±15.4 years; median BMI: 26.6, IQR: 5.9) with suspected pulmonary embolism were examined with two different protocols (n = 50 each, group A: 80 kVp, ref. mAs 115, 25 ml of contrast medium; group B: 100 kVp, ref. mAs 150, 60 ml of contrast medium) using a dual-source CT equipped with automated exposure control. Objective and subjective image qualities, radiation exposure as well as the frequency of pulmonary embolism were evaluated. Results There was no significant difference in subjective image quality scores between two groups regarding pulmonary arteries (p = 0.776), whereby the interobserver agreement was excellent (group A: k = 0.9; group B k = 1.0). Objective image analysis revealed that signal intensities (SI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the pulmonary arteries were equal or significantly higher in group B. There was no significant difference in the frequency of pulmonary embolism (p = 0.65). Using the low dose and low contrast media protocol resulted in a radiation dose reduction by 71.8% (2.4 vs. 0.7 mSv; p<0.001). Conclusions This 80 kVp standard pitch CTPA protocol with 25 ml contrast agent volume can obtain sufficient image quality to exclude or diagnose pulmonary emboli while reducing radiation dose by approximately 71%.
Collapse
Affiliation(s)
- Saravanabavaan Suntharalingam
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
- * E-mail:
| | - Christian Mikat
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Elena Stenzel
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Youssef Erfanian
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Axel Wetter
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Thomas Schlosser
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Michael Forsting
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Kai Nassenstein
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| |
Collapse
|
6
|
Use of low tube voltage and low contrast agent concentration yields good image quality for aortic CT angiography. Clin Radiol 2016; 71:1313.e5-1313.e10. [DOI: 10.1016/j.crad.2016.07.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 07/20/2016] [Accepted: 07/25/2016] [Indexed: 11/22/2022]
|
7
|
Strategies to Lessen the Radiation Risk from CT: A Multination Perspective. CURRENT RADIOLOGY REPORTS 2016. [DOI: 10.1007/s40134-016-0186-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
8
|
Abstract
As endoscopic sinus surgery (ESS) has evolved since its introduction to the United States, so has technology for imaging the sinonasal cavities. Although imaging is most frequently performed for evaluating chronic sinusitis refractory to medical therapy, its uses have expanded beyond inflammatory sinus disease. Multidetector Computed Tomography is the current workhorse for both diagnosis and preoperative planning in prospective ESS patients, while MR imaging remains a complementary tool for evaluating suspected tumors or intracranial and orbital complications of rhinosinusitis. In this article, the authors review current trends and potential future directions in the use of these modalities for sinus imaging.
Collapse
Affiliation(s)
- Benjamin Y Huang
- Department of Radiology, University of North Carolina, CB# 7510, 101 Manning Drive, Chapel Hill, NC 27599, USA.
| | - Brent A Senior
- Department of Otolaryngology-Head and Neck Surgery, University of North Carolina, CB# 7070, 170 Manning Drive, Chapel Hill, NC 27599, USA
| | - Mauricio Castillo
- Department of Radiology, University of North Carolina, CB# 7510, 101 Manning Drive, Chapel Hill, NC 27599, USA
| |
Collapse
|
9
|
Durmus T, Luhur R, Daqqaq T, Schwenke C, Knobloch G, Huppertz A, Hamm B, Lembcke A. Individual selection of X-ray tube settings in computed tomography coronary angiography: Reliability of an automated software algorithm to maintain constant image quality. Eur J Radiol 2016; 85:963-71. [PMID: 27130057 DOI: 10.1016/j.ejrad.2016.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 02/28/2016] [Accepted: 03/02/2016] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To evaluate a software tool that claims to maintain a constant contrast-to-noise ratio (CNR) in high-pitch dual-source computed tomography coronary angiography (CTCA) by automatically selecting both X-ray tube voltage and current. METHODS A total of 302 patients (171 males; age 61±12years; body weight 82±17kg, body mass index 27.3±4.6kg/cm(2)) underwent CTCA with a topogram-based, automatic selection of both tube voltage and current using dedicated software with quality reference values of 100kV and 250mAs/rotation (i.e., standard values for an average adult weighing 75kg) and an injected iodine load of 222mg/kg. RESULTS The average radiation dose was estimated to be 1.02±0.64mSv. All data sets had adequate contrast enhancement. Average CNR in the aortic root, left ventricle, and left and right coronary artery was 15.7±4.5, 8.3±2.9, 16.1±4.3 and 15.3±3.9 respectively. Individual CNR values were independent of patients' body size and radiation dose. However, individual CNR values may vary considerably between subjects as reflected by interquartile ranges of 12.6-18.6, 6.2-9.9, 12.8-18.9 and 12.5-17.9 respectively. Moreover, average CNR values were significantly lower in males than females (15.1±4.1 vs. 16.6±11.7 and 7.9±2.7 vs. 8.9±3.0, 15.5±3.9 vs. 16.9±4.6 and 14.7±3.6 vs. 16.0±4.1 respectively). CONCLUSION A topogram-based automatic selection of X-ray tube settings in CTCA provides diagnostic image quality independent of patients' body size. Nevertheless, considerable variation of individual CNR values between patients and significant differences of CNR values between males and females occur which questions the reliability of this approach.
Collapse
Affiliation(s)
- Tahir Durmus
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany.
| | - Reny Luhur
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Tareef Daqqaq
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | | | - Gesine Knobloch
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | | | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Alexander Lembcke
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| |
Collapse
|
10
|
Han BK, Rigsby CK, Leipsic J, Bardo D, Abbara S, Ghoshhajra B, Lesser JR, Raman SV, Crean AM, Nicol ED, Siegel MJ, Hlavacek A. Computed Tomography Imaging in Patients with Congenital Heart Disease, Part 2: Technical Recommendations. An Expert Consensus Document of the Society of Cardiovascular Computed Tomography (SCCT). J Cardiovasc Comput Tomogr 2015; 9:493-513. [DOI: 10.1016/j.jcct.2015.07.007] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 07/17/2015] [Indexed: 02/06/2023]
|
11
|
Objective and subjective image quality of primary and recurrent squamous cell carcinoma on head and neck low-tube-voltage 80-kVp computed tomography. Neuroradiology 2015; 57:645-51. [DOI: 10.1007/s00234-015-1512-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 03/13/2015] [Indexed: 11/24/2022]
|
12
|
Zhang C, Yu Y, Zhang Z, Wang Q, Zheng L, Feng Y, Zhou Z, Zhang G, Li K. Imaging quality evaluation of low tube voltage coronary CT angiography using low concentration contrast medium. PLoS One 2015; 10:e0120539. [PMID: 25811785 PMCID: PMC4374912 DOI: 10.1371/journal.pone.0120539] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 01/23/2015] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To compare the image quality of prospectively ECG-gated low voltage coronary computed tomography angiography (CTA) with an administration of low concentration contrast medium. METHOD AND MATERIALS A total of 101 patients, each with a heart rate below 65 beats per minute (BPM), underwent a prospectively ECG-gated axial scan in CT coronary angiography on a 64-slice CT scanner. All patients were allocated in three groups (group A: n=31, 80 kVp, 300 mgI/ml; group B: n=34, 100 kVp, 300 mgI/ml; group C: n=36, 120 kVp, 370 mgI/ml). The CT attenuation values of aortic root (AR), left main coronary artery (LMA), right main coronary artery (RMA) and chest subcutaneous fat tissue were measured. The contrast-to-noise ratio (CNR) of AR, LMA and RMA were calculated according to the formulas below. The values of computed tomography dose index (CTDI) and dose-length product (DLP) were recorded. Image quality was assessed on a 5-point scale. The results were compared using the one-way ANOVA and rank sum tests. RESULTS The values of CNR and SNR for vessels in group A and group B were not significantly different from group C (each p > 0.05). The effective radiation dose in group A (1.51 ± 0.70 mSv) and group B (2.59 ± 1.24 mSv) were both lower than group C (4.92 ± 2.82 mSv) (each p < 0.05). There was no significant difference among the image quality scores of group A (4.10 ± 0.41), group B (3.90 ± 0.48) and group C (4.04 ± 0.36) (each P > 0.05). CONCLUSION Low tube voltage coronary CT angiography using low concentration contrast medium does not affect the imaging quality for assessing the coronary arteries compared with high voltage coronary CT angiography using high concentration contrast medium. Meanwhile low concentration contrast medium allowed 47-69% of radiation dose reduction.
Collapse
Affiliation(s)
- Chengzhong Zhang
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| | - Yuejun Yu
- Department of Interventional Radiology, Weifang People's Hospital, Weifang, Shandong, People’s Republic of China
| | - Zaixian Zhang
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| | - Qingguo Wang
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| | - Linfeng Zheng
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| | - Yan Feng
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| | - Zhiguo Zhou
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| | - Guixiang Zhang
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| | - Kangan Li
- Department of Radiology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China
| |
Collapse
|
13
|
Non-linear image blending improves visualization of head and neck primary squamous cell carcinoma compared to linear blending in dual-energy CT. Clin Radiol 2015; 70:168-75. [DOI: 10.1016/j.crad.2014.10.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 10/26/2014] [Accepted: 10/30/2014] [Indexed: 11/20/2022]
|
14
|
Zhang J, He B, Wang YL, Han D. Application of 270 mgI/mL Iodinated Contrast Media in Dual-Source Computed Tomography Coronary Artery Imaging. ACTA CARDIOLOGICA SINICA 2014; 30:538-45. [PMID: 27122832 DOI: 10.6515/acs20140421a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND This study aimed to explore the application of 270 mg I/mL iodinated contrast agent with a tube voltage of 100 kV scanning in coronary computed tomography angiography (CCTA). METHODS This CCTA study was a prospective observational study. The two radiologists were blinded to both patient information and image date arrangement. One-hundred twenty patients (body mass index < 25.0 kg/m(2)) were randomly divided into three groups based on contrast agent concentrations of 370, 320, and 270 mg I/mL, scanning at an injection rate of 5 ml/s. Then, the coronary artery branches of the three groups were compared, and the display rate, mean computed tomography (CT) value, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), image noise, and radiation dose were analyzed. RESULTS The artery display rates of the four main branches of coronaries in the three groups were all 100%, and the difference in the display rates of the remaining small branches in the three groups exhibited no statistical significance (p > 0.05). A comparison of the mean CT value of the coronary artery of three groups in the ascending aorta, descending aorta, left main, left ventricular wall, right coronary artery, left anterior descending, and left circumflex showed a statistically significant difference (p < 0.05). A comparison of the SNR, CNR, image noise, and radiation dose showed no statistically significant difference (p > 0.05). CONCLUSIONS Using a tube voltage of 100 kV combined with 270 mg I/mL iodinated contrast media in CCTA examination can achieve the "double low dose" effect while ensuring image quality. KEY WORDS Contrast agent; Contrast to noise ratio; Coronary angiography; Signal noise ratio.
Collapse
Affiliation(s)
- Jun Zhang
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, Kunming 650032, China
| | - Bo He
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, Kunming 650032, China
| | - Yuan-Ling Wang
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, Kunming 650032, China
| | - Dan Han
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, Kunming 650032, China
| |
Collapse
|
15
|
Raman SP, Mahesh M, Blasko RV, Fishman EK. CT scan parameters and radiation dose: practical advice for radiologists. J Am Coll Radiol 2014; 10:840-6. [PMID: 24183553 DOI: 10.1016/j.jacr.2013.05.032] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/29/2013] [Indexed: 10/26/2022]
Abstract
Although there has been increasing recognition of the importance of reducing radiation dose when performing multidetector CT examinations, the increasing complexity of CT scanner technology, as well as confusion about the importance of many different CT scan parameters, has served as an impediment to radiologists seeking to create lower dose protocols. The authors seek to guide radiologists through the manipulation of 8 fundamental CT scan parameters that can be altered or optimized to reduce patient radiation dose, including detector configuration, tube current, tube potential, reconstruction algorithm, patient positioning, scan range, reconstructed slice thickness, and pitch. Although there is always an inherent trade-off between image quality or noise and patient radiation dose, in many cases, a reasoned manipulation of these 8 parameters can allow the safer imaging of patients (with lower dose) while preserving diagnostic image quality.
Collapse
Affiliation(s)
- Siva P Raman
- Department of Radiology, Johns Hopkins University, Baltimore, Maryland.
| | | | | | | |
Collapse
|
16
|
Can dual-energy CT improve the assessment of tumor margins in oral cancer? Oral Oncol 2013; 50:221-7. [PMID: 24373911 DOI: 10.1016/j.oraloncology.2013.12.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 11/28/2013] [Accepted: 12/02/2013] [Indexed: 12/16/2022]
Abstract
OBJECTIVES The aim was to investigate the image quality of dual-energy computed-tomography (DECT) compared to single-energy images at 80 kV and 140 kV in oral tumors. MATERIALS AND METHODS Forty patients underwent a contrast-enhanced DECT scan on a definition flash-CT. Four reconstructions (80 kV, 140 kV, mixed (M), and optimum-contrast (OC)) were assessed by four blinded readers for subjective image quality (10-point scale/10=best). For objective quality assessment, linear attenuation measurements (line density profiles (LDP)) were positioned at the tumor margin, and the difference between minimum and maximum was calculated. Signal-to-noise ratios (SNR) were measured in the tongue. RESULTS The mean image quality for all readers was 5.1±0.3, 8.4±0.3, 8.1±0.2, and 8.3±0.2 for the 140 kV, 80 kV, M, and OC, respectively (P<001 between 140 kV and all others). The mean difference between the minimum and maximum within the LDP was 139.4±59.0, 65.7±29.5, 105.1±46.5, and 118.7±59.4 for the 80 kV, 140 kV, M, and OC, respectively (P<001). The SNR for the tongue was 3.8±2.1, 3.8±2.1, 4.2±2.4, and 4.1±2.3 for the 80 kV, 140 kV, M, and OC, respectively. DISCUSSION DECT of oral tumors offers high image quality, with subjectively rated image quality and attenuation contrast at the tumor margin similar to that of 80 kV; DECT, however, provides a significantly higher SNR compared to 80 kV.
Collapse
|
17
|
Raman SP, Johnson PT, Deshmukh S, Mahesh M, Grant KL, Fishman EK. CT dose reduction applications: available tools on the latest generation of CT scanners. J Am Coll Radiol 2013; 10:37-41. [PMID: 23290672 DOI: 10.1016/j.jacr.2012.06.025] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 06/18/2012] [Indexed: 12/23/2022]
Abstract
Increasing concerns about radiation dose have led CT manufacturers to further develop radiation dose reduction tools in the latest generation of CT scanners. These tools include automated tube current modulation, automated tube potential selection, and iterative reconstruction. This review details the principles underlying each of these 3 dose reduction utilities and their different permutations on each of the major vendors' equipment. If available on the user's equipment, all 3 of these tools should be used in conjunction to enable maximum radiation dose savings.
Collapse
Affiliation(s)
- Siva P Raman
- Department of Radiology, Johns Hopkins University, Baltimore, MD 21287, USA.
| | | | | | | | | | | |
Collapse
|
18
|
Williams MC, Weir NW, Mirsadraee S, Millar F, Baird A, Minns F, Uren NG, McKillop G, Bull RK, van Beek EJR, Reid JH, Newby DE. Iterative reconstruction and individualized automatic tube current selection reduce radiation dose while maintaining image quality in 320-multidetector computed tomography coronary angiography. Clin Radiol 2013; 68:e570-7. [PMID: 23838086 PMCID: PMC3807656 DOI: 10.1016/j.crad.2013.05.098] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 05/13/2013] [Accepted: 05/29/2013] [Indexed: 01/22/2023]
Abstract
AIM To assess the effect of two iterative reconstruction algorithms (AIDR and AIDR3D) and individualized automatic tube current selection on radiation dose and image quality in computed tomography coronary angiography (CTCA). MATERIALS AND METHODS In a single-centre cohort study, 942 patients underwent electrocardiogram-gated CTCA using a 320-multidetector CT system. Images from group 1 (n = 228) were reconstructed with a filtered back projection algorithm (Quantum Denoising Software, QDS+). Iterative reconstruction was used for group 2 (AIDR, n = 379) and group 3 (AIDR3D, n = 335). Tube current was selected based on body mass index (BMI) for groups 1 and 2, and selected automatically based on scout image attenuation for group 3. Subjective image quality was graded on a four-point scale (1 = excellent, 4 = non-diagnostic). RESULTS There were no differences in age (p = 0.975), body mass index (p = 0.435), or heart rate (p = 0.746) between the groups. Image quality improved with iterative reconstruction and automatic tube current selection [1.3 (95% confidence intervals (CI): 1.2-1.4), 1.2 (1.1-1.2) and 1.1 (1-1.2) respectively; p < 0.001] and radiation dose decreased [274 (260-290), 242 (230-253) and 168 (156-180) mGy cm, respectively; p < 0.001]. CONCLUSION The application of the latest iterative reconstruction algorithm and individualized automatic tube current selection can substantially reduce radiation dose whilst improving image quality in CTCA.
Collapse
Affiliation(s)
- M C Williams
- University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, Edinburgh, UK.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|