1
|
Lee WC, Poon JK, Siah JJH, Chong MC, Lai C. Feasibility of low contrast volume and low injection flow rate in CT pulmonary angiography. J Med Imaging Radiat Sci 2024:101349. [PMID: 38897899 DOI: 10.1016/j.jmir.2023.11.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/12/2023] [Accepted: 11/22/2023] [Indexed: 06/21/2024]
Abstract
BACKGROUND Computed Tomography Pulmonary Angiography (CTPA) is currently the gold standard for diagnosing Pulmonary Embolism (PE), with a high flowrate (>4.5ml/s) for contrast media (CM) administration recommended for sufficient pulmonary artery opacification. However, this may not be achievable for patients with challenging IV access. AIM To determine if a low volume CM, low flowrate (LVLF) CTPA protocol produces images of similar image quality compared to a standard protocol in two aspects, in terms of peak arterial enhancement through the quantitative measurement of Hounsfield unit (HU) and based on subjective overall image quality. METHODS Retrospective collection of 151 patients who underwent CTPA via 320 slice multi-detector CT due to clinical suspicion of PE. 80 patients underwent the standard protocol, with a fixed flowrate of 4.5ml/s and 50ml of CM, while 71 patients underwent the LVLF protocol with up to a 37% and 30% reduction in flowrate and CM administered, respectively. Two independent radiographers measured the attenuation of multiple pulmonary arteries in HU, with ≥200HU being considered diagnostic. Overall image quality was also reviewed using a 5-point close-ended questionnaire by two independent radiologists. RESULTS There was no significant difference in terms of attenuation measured in HU for the seven regions of interest (main pulmonary trunk, right and left pulmonary arteries, right and left lobar arteries, and right and left subsegmental arteries (RSA and LSA)) between the LVLF and standard CTPA protocol. Similarly, there were no significant differences in the overall image quality score obtained from standard and LVLF protocols reported by both radiologists. CONCLUSION The LVLF protocol can achieve similar enhancement and subjective image quality as the standard CTPA protocol, potentially allowing for further optimisation in the CM dosage.
Collapse
Affiliation(s)
- Wan Chin Lee
- Radiography, Changi General Hospital, Singapore.
| | - Jun Kai Poon
- Health and Social Science Cluster, Singapore Institute of Technology, Singapore, Singapore
| | | | | | - Christopher Lai
- Health and Social Science Cluster, Singapore Institute of Technology, Singapore, Singapore
| |
Collapse
|
2
|
Schönfeld T, Seitz P, Krieghoff C, Ponorac S, Wötzel A, Olthoff S, Schaudt S, Steglich J, Gutberlet M, Gohmann RF. High-pitch CT pulmonary angiography (CTPA) with ultra-low contrast medium volume for the detection of pulmonary embolism: a comparison with standard CTPA. Eur Radiol 2024; 34:1921-1931. [PMID: 37656178 PMCID: PMC10873234 DOI: 10.1007/s00330-023-10101-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 06/29/2023] [Accepted: 07/05/2023] [Indexed: 09/02/2023]
Abstract
OBJECTIVE To investigate the feasibility and image quality of high-pitch CT pulmonary angiography (CTPA) with reduced iodine volume in normal weight patients. METHODS In total, 81 normal weight patients undergoing CTPA for suspected pulmonary arterial embolism were retrospectively included: 41 in high-pitch mode with 20 mL of contrast medium (CM); and 40 with normal pitch and 50 mL of CM. Subjective image quality was assessed and rated on a 3-point scale. For objective image quality, attenuation and noise values were measured in all pulmonary arteries from the trunk to segmental level. Contrast-to-noise ratio (CNR) was calculated. Radiation dose estimations were recorded. RESULTS There were no statistically significant differences in patient and scan demographics between high-pitch and standard CTPA. Subjective image quality was rated good to excellent in over 90% of all exams with no significant group differences (p = 0.32). Median contrast opacification was lower in high-pitch CTPA (283.18 [216.06-368.67] HU, 386.81 [320.57-526.12] HU; p = 0.0001). CNR reached a minimum of eight in all segmented arteries, but was lower in high-pitch CTPA (8.79 [5.82-12.42], 11.01 [9.19-17.90]; p = 0.005). Median effective dose of high-pitch CTPA was lower (1.04 [0.72-1.27] mSv/mGy·cm; 1.49 [1.07-2.05] mSv/mGy·cm; p < 0.0001). CONCLUSION High-pitch CTPA using ultra-low contrast volume (20 mL) rendered diagnostic images for the detection of pulmonary arterial embolism in most instances. Compared to standard CTPA, the high-pitch CTPA exams with drastically reduced contrast medium volume had also concomitantly reduced radiation exposure. However, objective image quality of high-pitch CTPA was worse, though likely still within acceptable limits for confident diagnosis. CLINICAL RELEVANCE This study provides valuable insights on the performance of a high-pitch dual-source CTPA protocol, offering potential benefits in reducing contrast medium and radiation dose while maintaining sufficient image quality for accurate diagnosis in patients suspected of pulmonary embolism. KEY POINTS • High-pitch CT pulmonary angiography (CTPA) with ultra-low volume of contrast medium and reduced radiation dose renders diagnostic examinations with comparable subjective image quality to standard CTPA in most patients. • Objective image quality of high-pitch CTPA is reduced compared to standard CTPA, but contrast opacification and contrast-to-noise ratio remain above diagnostic thresholds. • Challenges of high-pitch CTPA may potentially be encountered in patients with severe heart failure or when performing a Valsalva maneuver during the examination.
Collapse
Affiliation(s)
- Tobias Schönfeld
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
- Department of General and Geriatric Medicine, St. Elisabeth-Hospital Leipzig, Biedermannstr. 84, 04277, Leipzig, Germany
- Medical Faculty, University of Leipzig, Liebigstr. 27, 04103, Leipzig, Germany
| | - Patrick Seitz
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Christian Krieghoff
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Slavica Ponorac
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
- Institute of Radiology, University Medical Centre Ljubljana, Zaloška Cesta 7, 1000, Ljubljana, Slovenia
| | - Alexander Wötzel
- Emergency Department, Helios Park-Clinic Leipzig, Strümpellstr. 41, 04289, Leipzig, Germany
| | - Stefan Olthoff
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Sebastian Schaudt
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
- Medical Faculty, University of Leipzig, Liebigstr. 27, 04103, Leipzig, Germany
| | - Jonas Steglich
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Matthias Gutberlet
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany
- Medical Faculty, University of Leipzig, Liebigstr. 27, 04103, Leipzig, Germany
- Leipzig Heart Institute, Russenstr. 69a, 04289, Leipzig, Germany
| | - Robin F Gohmann
- Department of Diagnostic and Interventional Radiology, Heart Center Leipzig, Strümpellstr. 39, 04289, Leipzig, Germany.
- Medical Faculty, University of Leipzig, Liebigstr. 27, 04103, Leipzig, Germany.
| |
Collapse
|
3
|
Saeed S, Niehoff JH, Boriesosdick J, Michael A, Woeltjen MM, Surov A, Moenninghoff C, Borggrefe J, Kroeger JR. Minimizing Contrast Media Dose in CT Pulmonary Angiography with Clinical Photon Counting Using High Pitch Technique. Acad Radiol 2024; 31:686-692. [PMID: 37393176 DOI: 10.1016/j.acra.2023.05.018] [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: 03/09/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 07/03/2023]
Abstract
RATIONALE AND OBJECTIVES To evaluate the potential to reduce the amount of iodinated contrast media (CM) for computer tomographic pulmonary angiography (CTPA) with a novel photon-counting-detector CT (PCCT). MATERIALS AND METHODS Overall, 105 patients referred for CTPA were retrospectively included in this study. CTPA was performed using bolus tracking and high-pitch dual-source scanning (FLASH mode) on a novel PCCT (Naeotom Alpha, Siemens Healthineers). CM (Accupaque 300, GE Healthcare) dose was lowered stepwise following the introduction of the new CT scanner. Thus, patients could be divided into 3 groups as follows: group 1, n = 29, 35 ml of CM; group 2, n = 62, 45 ml of CM and group 3, n = 14, 60 ml of CM. Four readers independently assessed the image quality (Likert-scale 1-5) and adequate assessment of the segmental pulmonary arteries. Additionally, the pulmonary arterial contrast opacification was measured. RESULTS The subjective image quality was rated highest in group 1 with 4.6 compared to 4.5 (group 2) and 4.1 (group 3) with a significant difference between groups 1 and 3 (p < 0.001) and between groups 2 and 3 (p = 0.003). In all groups, almost all segmental pulmonary arteries could be assessed adequately without significant differences (18.5 vs. 18.7 vs. 18.4). Mean attenuation in the pulmonary trunk did not differ significantly between groups 321 ± 92 HU versus 345 ± 93 HU versus 347 ± 88 HU (p = 0.69). CONCLUSION Significant CM dose reduction is possible without a reduction in image quality. PCCT enables diagnostic CTPA with 35 ml of CM.
Collapse
Affiliation(s)
- Saher Saeed
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany.
| | - Julius H Niehoff
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Jan Boriesosdick
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Arwed Michael
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Matthias M Woeltjen
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Alexey Surov
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Christoph Moenninghoff
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Jan Borggrefe
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Jan Robert Kroeger
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| |
Collapse
|
4
|
Geng W, Gao Y, Zhao N, Yan H, Ma W, An Y, Jia L, Lu B. Dose Reduction of Dynamic Computed Tomography Myocardial Perfusion Imaging by Tube Voltage Change: Investigation in a Swine Model. Front Cardiovasc Med 2022; 9:823974. [PMID: 35310988 PMCID: PMC8927626 DOI: 10.3389/fcvm.2022.823974] [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: 11/28/2021] [Accepted: 02/15/2022] [Indexed: 11/18/2022] Open
Abstract
Background It is unclear whether tube voltage influences the measurement of perfusion parameters. The present study sought to evaluate the influence of tube voltage change on myocardial blood flow (MBF) measurements in dynamic computed tomography myocardial perfusion imaging (CTP). Methods and Results Seven swine [mean weight 55.8 kg ± 1.6 (standard deviation)] underwent rest and stress dynamic CTP with tube voltages of 100 and 70 kV. The image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), radiation dose and MBF value were compared. The 70 kV images had higher CT attenuation and higher image noise (27.9 ± 2.4 vs. 21.5 ± 1.9, P < 0.001) than the 100 kV images, resulting in a higher SNR (20.5 ± 1.6 vs. 15.6 ± 1.8, P < 0.001) and CNR (17.6 ± 1.5 vs. 12.4 ± 1.7, P < 0.001). Compared to the use of conventional 100 kV, 70 kV yielded an approximately 64.6% radiation dose reduction while generating comparable MBF values, both at rest (88.3 ± 14.9 ml/100 g/min vs. 85.6 ± 17.4 ml/100 g/min, P = 0.21) and stress (101.4 ± 21.5 ml/100 g/min vs. 99.6 ± 21.4 ml/100 g/min, P = 0.58) states. Conclusion Dynamic CTP using 70 kV instead of 100 kV does not substantially influence the MBF value but significantly reduces the radiation dose. Additional research is required to investigate the clinical significance of this change.
Collapse
Affiliation(s)
- Wenlei Geng
- Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Yang Gao
- Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Na Zhao
- Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Hankun Yan
- Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Wei Ma
- Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Yunqiang An
- Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Liujun Jia
- Animal Experimental Center, Beijing Key Laboratory of Pre-Clinical Research and Evaluation for Cardiovascular Implant Materials, State Key Laboratory of Cardiovascular Disease, Beijing, China
| | - Bin Lu
- Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
- *Correspondence: Bin Lu,
| |
Collapse
|
5
|
Acute Pulmonary Embolism: Prognostic Role of Computed Tomography Pulmonary Angiography (CTPA). Tomography 2022; 8:529-539. [PMID: 35202207 PMCID: PMC8880178 DOI: 10.3390/tomography8010042] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 02/06/2022] [Accepted: 02/08/2022] [Indexed: 12/24/2022] Open
Abstract
Computed Tomography Pulmonary Angiography (CTPA) is considered the gold standard diagnostic technique in patients with suspected acute pulmonary embolism in emergency departments. Several studies have been conducted on the predictive value of CTPA on the outcomes of pulmonary embolism (PE). The purpose of this article is to provide an updated review of the literature reporting imaging parameters and quantitative CT scores to predict the severity of PE.
Collapse
|
6
|
Vlahos I, Jacobsen MC, Godoy MC, Stefanidis K, Layman RR. Dual-energy CT in pulmonary vascular disease. Br J Radiol 2022; 95:20210699. [PMID: 34538091 PMCID: PMC8722250 DOI: 10.1259/bjr.20210699] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Dual-energy CT (DECT) imaging is a technique that extends the capabilities of CT beyond that of established densitometric evaluations. CT pulmonary angiography (CTPA) performed with dual-energy technique benefits from both the availability of low kVp CT data and also the concurrent ability to quantify iodine enhancement in the lung parenchyma. Parenchymal enhancement, presented as pulmonary perfused blood volume maps, may be considered as a surrogate of pulmonary perfusion. These distinct capabilities have led to new opportunities in the evaluation of pulmonary vascular diseases. Dual-energy CTPA offers the potential for improvements in pulmonary emboli detection, diagnostic confidence, and most notably severity stratification. Furthermore, the appreciated insights of pulmonary vascular physiology conferred by DECT have resulted in increased use for the assessment of pulmonary hypertension, with particular utility in the subset of patients with chronic thromboembolic pulmonary hypertension. With the increasing availability of dual energy-capable CT systems, dual energy CTPA is becoming a standard-of-care protocol for CTPA acquisition in acute PE. Furthermore, qualitative and quantitative pulmonary vascular DECT data heralds promise for the technique as a "one-stop shop" for diagnosis and surveillance assessment in patients with pulmonary hypertension. This review explores the current application, clinical value, and limitations of DECT imaging in acute and chronic pulmonary vascular conditions. It should be noted that certain manufacturers and investigators prefer alternative terms, such as spectral or multi-energy CT imaging. In this review, the term dual energy is utilised, although readers can consider these terms synonymous for purposes of the principles explained.
Collapse
Affiliation(s)
- Ioannis Vlahos
- Department of Thoracic Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Megan C Jacobsen
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Myrna C Godoy
- Department of Thoracic Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Rick R Layman
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| |
Collapse
|
7
|
Nguyen ET, Hague C, Manos D, Memauri B, Souza C, Taylor J, Dennie C. Canadian Society of Thoracic Radiology/Canadian Association of Radiologists Best Practice Guidance for Investigation of Acute Pulmonary Embolism, Part 1: Acquisition and Safety Considerations. Can Assoc Radiol J 2021; 73:203-213. [PMID: 33781098 DOI: 10.1177/08465371211000737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Acute pulmonary embolism (APE) is a well-recognized cause of circulatory system compromise and even demise which can frequently present a diagnostic challenge for the physician. The diagnostic challenge is primarily due to the frequency of indeterminate presentations as well as several other conditions which can have a similar clinical presentation. This often obliges the physician to establish a firm diagnosis due to the potentially serious outcomes related to this disease. Computed tomography pulmonary angiography (CTPA) has increasingly cemented its role as the primary investigation tool in this clinical context and is widely accepted as the standard of care due to several desired attributes which include great accuracy, accessibility, rapid turn-around time and the ability to suggest an alternate diagnosis when APE is not the culprit. In Part 1 of this guidance document, a series of up-to-date recommendations are provided to the reader pertaining to CTPA protocol optimization (including scan range, radiation and intravenous contrast dose), safety measures including the departure from breast and gonadal shielding, population-specific scenarios (pregnancy and early post-partum) and consideration of alternate diagnostic techniques when clinically deemed appropriate.
Collapse
Affiliation(s)
- Elsie T Nguyen
- Department of Radiology, Joint Department of Medical Imaging, Toronto General Hospital, University of Toronto, Ontario, Canada
| | - Cameron Hague
- Department of Radiology, University of British Columbia, Ontario, Canada
| | - Daria Manos
- Department of Diagnostic Radiology, Dalhousie University, Ontario, Canada
| | - Brett Memauri
- Department of Radiology, University of Manitoba, Cardiothoracic Sciences Division, St. Boniface General Hospital, Ontario, Canada
| | - Carolina Souza
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ontario, Canada
| | - Jana Taylor
- Department of Radiology, McGill University Health Centre, Ontario, Canada
| | - Carole Dennie
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ontario, Canada.,Department of Radiology, University of Ottawa, Ottawa Hospital Research Institute, Ontario, Canada
| |
Collapse
|
8
|
Aldosari S, Sun Z. A Systematic Review of Double Low-dose CT Pulmonary Angiography in Pulmonary Embolism. Curr Med Imaging 2020; 15:453-460. [PMID: 32008552 DOI: 10.2174/1573405614666180813120619] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 07/20/2018] [Accepted: 07/31/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND The aim of this study is to perform a systematic review of the feasibility and clinical application of double low-dose CT pulmonary angiography (CTPA) in the diagnosis of patients with suspected pulmonary embolism. DISCUSSION A total of 13 studies were found to meet selection criteria reporting both low radiation dose (70 or 80 kVp versus 100 or 120 kVp) and low contrast medium dose CTPA protocols. Lowdose CTPA resulted in radiation dose reduction from 29.6% to 87.5% in 12 studies (range: 0.4 to 23.5 mSv), while in one study, radiation dose was increased in the dual-energy CT group when compared to the standard 120 kVp group. CTPA with use of low contrast medium volume (range: 20 to 75 ml) was compared to standard CTPA (range: 50 to 101 ml) in 12 studies with reduction between 25 and 67%, while in the remaining study, low iodine concentration was used with 23% dose reduction achieved. Quantitative assessment of image quality (in terms of signal-to-noise ratio and contrast-to-noise ratio) showed that low-dose CTPA was associated with higher, lower and no change in image quality in 3, 3 and 6 studies, respectively when compared to the standard CTPA protocol. The subjective assessment indicated similar image quality in 11 studies between low-dose and standard CTPA groups, and improved image quality in 1 study with low-dose CTPA. CONCLUSION This review shows that double low-dose CTPA is feasible in the diagnosis of pulmonary embolism with significant reductions in both radiation and contrast medium doses, without compromising diagnostic image quality.
Collapse
Affiliation(s)
- Sultan Aldosari
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Australia
| | - Zhonghua Sun
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Australia
| |
Collapse
|
9
|
Chi J, Xu D, Yin S, Li M, Shen L, Ding N, Chen X, Ji Y. Reducing the radiation dose of pediatric paranasal sinus CT using an ultralow tube voltage (70 kVp) combined with iterative reconstruction: Feasibility and image quality. Medicine (Baltimore) 2020; 99:e21886. [PMID: 32846848 PMCID: PMC7447483 DOI: 10.1097/md.0000000000021886] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND As the gold standard for imaging sinus disease, the main disadvantage of computed tomography (CT) of the pediatric paranasal sinus is radiation exposure. Because of this, 1 protocol for CT should reduce radiation dose while maintaining image quality. The aim of this study is to evaluate the image quality of dose-reduced paranasal sinus computed tomography (CT) using an ultralow tube voltage (70 kVp) combined with iterative reconstruction (IR) in children. METHODS CT scans of the paranasal sinus were performed using different protocols [70 kVp protocols with IR, Group A, n = 80; 80 kVp protocols with a filtered back projection algorithm, Group B, n = 80] in 160 pediatric patients. Then, the volume-weighted CT dose index, dose-length product, and effective dose were estimated. Image noise, the signal-to-noise ratio and the diagnostic image quality were also evaluated. RESULTS For the radiation dose, the volume-weighted CT dose index, dose-length product and effective dose values were significantly lower for the 70 kVp protocols than for the 80 kVp protocols (P < .001). Compared with the 80 kVp protocols, the 70 kVp protocols had significantly higher levels of image noise (P = .001) and a lower signal-to-noise ratio (P = .002). No significant difference in the overall subjective image quality grades was observed between these 2 groups (P = .098). CONCLUSION The ultralow tube voltage (70 kVp) technique combined with IR enabled a significant dose reduction in CT examinations performed in the pediatric paranasal sinus while maintaining diagnostic image quality with clinically acceptable image noise.
Collapse
|
10
|
Alobeidi H, Alshamari M, Widell J, Eriksson T, Lidén M. Minimizing contrast media dose in CT pulmonary angiography with high-pitch technique. Br J Radiol 2020; 93:20190995. [PMID: 32436788 PMCID: PMC7336071 DOI: 10.1259/bjr.20190995] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/30/2020] [Accepted: 04/23/2020] [Indexed: 02/01/2023] Open
Abstract
OBJECTIVES To perform CT pulmonary angiography (CTPA) using a minimal amount of iodinated contrast media. METHODS 47 patients (25 females) with mean age 69 years (range 41-82 years) referred for contrast-enhanced chest CT were prospectively included in this Phase IV clinical drug trial. All participants underwent a study specific CTPA in addition to the chest CT. The participants received 80 mg I/kg body weight Iohexol contrast media using a preparatory saline bolus, a dual flow contrast/saline bolus and a saline flush, and a scanner protocol with 80 kVp dual source high-pitch mode. Three readers independently assessed the image quality on the 3-point scale non-diagnostic, adequate or good-excellent image quality. Additionally, the pulmonary arterial contrast opacification was measured. RESULTS On average, the patients received 16.8 ml Iohexol 350 mg I/mL (range 12-20 ml). Mean patient weight was 71 kg (range 50-85 kg). Identically for all readers, pulmonary embolism (PE) was detected in 1/47 participants. The median number of examinations visually scored concerning pulmonary embolism as good-excellent was 47/47 (range 44-47); adequate 0/47 (0-3) and non-diagnostic 0/47 (range 0-0). The proportion adequate or better examinations was for all readers 47/47, 100% [95% confidence interval 92-100%]. The mean attenuation ± standard deviation in the pulmonary trunk was 325 ± 72 Hounsfield unit (range 165-531 Hounsfield unit). CONCLUSIONS Diagnostic CTPA with 17 ml contrast media is possible in non-obese patients using low kVp, high pitch and carefully designed contrast media administration. ADVANCES IN KNOWLEDGE By combining several procedures in a CTPA protocol, the contrast media dose can be minimized.
Collapse
Affiliation(s)
- Hanan Alobeidi
- Department of Radiology, Örebro university Hospital, Region Örebro län, S-70185 Örebro, Sweden
| | - Muhammed Alshamari
- Department of Radiology, Faculty of Medicine and Health, Örebro University, S-70182 Örebro, Sweden
| | - Jonas Widell
- Department of Radiology, Örebro university Hospital, Region Örebro län, S-70185 Örebro, Sweden
| | - Tomas Eriksson
- Department of Radiology, Örebro university Hospital, Region Örebro län, S-70185 Örebro, Sweden
| | - Mats Lidén
- Department of Radiology, Faculty of Medicine and Health, Örebro University, S-70182 Örebro, Sweden
| |
Collapse
|
11
|
Rajiah P, Ciancibello L, Novak R, Sposato J, Landeras L, Gilkeson R. Ultra-low dose contrast CT pulmonary angiography in oncology patients using a high-pitch helical dual-source technology. ACTA ACUST UNITED AC 2020; 25:195-203. [PMID: 31063136 DOI: 10.5152/dir.2019.17498] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
PURPOSE We aimed to determine if the image quality and vascular enhancement are preserved in computed tomography pulmonary angiography (CTPA) studies performed with ultra-low contrast and optimized radiation dose using high-pitch helical mode of a second generation dual source scanner. METHODS We retrospectively evaluated oncology patients who had CTPA on a 128-slice dual-source scanner, with a high-pitch helical mode (3.0), following injection of 30 mL of Ioversal at 4 mL/s with body mass index (BMI) dependent tube potential (80-120 kVp) and current (130-150 mAs). Attenuation, noise, and signal-to-noise ratio (SNR) were measured in multiple pulmonary arteries. Three independent readers graded the images on a 5-point Likert scale for central vascular enhancement (CVE), peripheral vascular enhancement (PVE), and overall quality. RESULTS There were 50 males and 101 females in our study. BMI ranged from 13 to 38 kg/m2 (22.8±4.4 kg/m2). Pulmonary embolism was present in 29 patients (18.9%). Contrast enhancement and SNR were excellent in all the pulmonary arteries (395.3±131.1 and 18.3±5.7, respectively). Image quality was considered excellent by all the readers, with average reader scores near the highest possible score of 5.0 (CVE, 4.83±0.48; PVE, 4.68±0.65; noise/quality, 4.78±0.47). The average radiation dose length product (DLP) was 161±60 mGy.cm. CONCLUSION Using a helical high-pitch acquisition technique, CTPA images of excellent diagnostic quality, including visualization of peripheral segmental/sub-segmental branches can be obtained using an ultra-low dose of iodinated contrast and low radiation dose.
Collapse
Affiliation(s)
- Prabhakar Rajiah
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA;Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Leslie Ciancibello
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| | - Ronald Novak
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA;Rebecca D. Considine Research Institute, Akron Children's Hospital, Akron, Ohio, USA
| | - Jennifer Sposato
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| | - Luis Landeras
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA;Department of Radiology, University of Chicago, Chicago, Illinois, USA
| | - Robert Gilkeson
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| |
Collapse
|
12
|
Kamr WH, El-Tantawy AM, Harraz MM, Tawfik AI. Pulmonary embolism: Low dose contrast MSCT pulmonary angiography with modified test bolus technique. Eur J Radiol Open 2020; 7:100254. [PMID: 32984447 PMCID: PMC7494793 DOI: 10.1016/j.ejro.2020.100254] [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: 07/28/2020] [Accepted: 08/24/2020] [Indexed: 11/04/2022] Open
Abstract
Test bolus technique increase the diagnostic quality score of the scans performed. Provides better evaluation of the pulmonary arteries and its subsegmental branches. Increase the main pulmonary artery average density, decrease average density of the aorta and pulmonary veins. Increase the confidence and accuracy rate of diagnostic examinations. Volume of IV contrast decreased by 40 % than in bolus tracking.
Purpose This study aims to prove that the test bolus technique provides a better selective imaging study of the pulmonary arterial system in comparison to the automatic bolus-tracking technique. Method A prospective study included 600 patients, classified into 2 groups where each group consisted of 300 patients. In group A, we used the bolus tracking technique with 80−100 ml of contrast while in group B test bolus technique was used with 50 mL of contrast. Results It was clear that the Main PA average density was 260.5 HU in group A and increased to 320 HU in group B with P value < 0.002. The Ascending aorta average density decreased from 250 HU in group A to 130 HU in group B with P value <.001. The average score was increased by 35 % (from 1.75 in group A to 2.8 in group B with P value < .001). The Volume of IV contrast needed decreased by 40 % in group B compared to group A. Conclusion MSCTPA using test bolus method reduces the amount of the contrast used with better opacification of the pulmonary artery and its sub segmental branches in addition to reduced artifact.
Collapse
|
13
|
Hendriks BMF, Schnerr RS, Milanese G, Jeukens CRLPN, Niesen S, Eijsvoogel NG, Wildberger JE, Das M. Computed Tomography Pulmonary Angiography during Pregnancy: Radiation Dose of Commonly Used Protocols and the Effect of Scan Length Optimization. Korean J Radiol 2019; 20:313-322. [PMID: 30672171 PMCID: PMC6342764 DOI: 10.3348/kjr.2017.0779] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 07/24/2018] [Indexed: 01/21/2023] Open
Abstract
Objective To evaluate the radiation dose for pregnant women and fetuses undergoing commonly used computed tomography of the pulmonary arteries (CTPA) scan protocols and subsequently evaluate the simulated effect of an optimized scan length. Materials and Methods A total of 120 CTPA datasets were acquired using four distinctive scan protocols, with 30 patients per protocol. These datasets were mapped to Cristy phantoms in order to simulate pregnancy and to assess the effect of an effective radiation dose (in mSv) in the first, second, or third trimester of pregnancy, including a simulation of fetal dose in second and third trimesters. The investigated scan protocols involved a 64-slice helical scan at 120 kVp, a high-pitch dual source acquisition at 100 kVp, a dual-energy acquisition at 80/140 kVp, and an automated-kV-selection, high pitch helical scan at a reference kV of 100 kVref. The effective dose for women and fetuses was simulated before and after scan length adaptation. The original images were interpreted before and after scan length adaptations to evaluate potentially missed diagnoses. Results Large inter-scanner and inter-protocol variations were found; application of the latest technology decreased the dose for non-pregnant women by 69% (7.0–2.2 mSv). Individual scan length optimization proved safe and effective, decreasing the fetal dose by 76–83%. Nineteen (16%) cases of pulmonary embolism were diagnosed and, after scan length optimization, none were missed. Conclusion Careful CTPA scan protocol selection and additional optimization of scan length may result in significant radiation dose reduction for a pregnant patient and her fetus, whilst maintaining diagnostic confidence.
Collapse
Affiliation(s)
- Babs M F Hendriks
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands.,CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands.
| | - Roald S Schnerr
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Gianluca Milanese
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands.,Department of Surgical Sciences, Division of Radiology, University of Parma, Parma, Italy
| | - Cécile R L P N Jeukens
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Sandra Niesen
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Nienke G Eijsvoogel
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands.,CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Joachim E Wildberger
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands.,CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Marco Das
- Department of Radiology & Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands.,Department of Diagnostic and Interventional Radiology, Duisburg, Germany
| |
Collapse
|
14
|
You SK, Choi YH, Cheon JE, Kim WS, Kim IO, Lee SM, Cho HH. Effect of low tube voltage and low iodine concentration abdominal CT on image quality and radiation dose in children: preliminary study. Abdom Radiol (NY) 2019; 44:1928-1935. [PMID: 30683980 DOI: 10.1007/s00261-019-01896-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE To evaluate the image quality of a double-low protocol (low tube voltage and low iodine concentration) for abdominal CT in children. MATERIALS AND METHODS The double-low protocol was compared to the conventional protocol in pediatric patients weighing less than 40 kg from May 2016 to December 2016. Double-low protocol (Group A, n = 18): tube voltage, 70 kVp; and iodine concentration,: 250 mgI/mL versus Conventional protocol (Group B, n = 13): tube voltage, 80-100 kVp; and iodine concentration, 350 mgI/mL. Mean attenuation, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were compared between the two groups. Image contrast, noise, beam-hardening artifacts, and overall image quality were subjectively scored. Reader performance for correctly differentiating two groups by visual assessment was evaluated. Radiation dose and total iodine load were recorded. RESULTS The mean attenuations of the portal vein and liver and the mean image noise in Group A were higher than in Group B (p = 0.04, 0.03, 0.004, respectively). The mean SNR and CNR of the main portal vein and liver were lower in Group A without any statistically significant difference. There were no statistically significant differences between the two groups in qualitative analysis (image contrast, image noise, and overall image quality) with substantial agreement between the reviewers (weighted kappa values; 0.59-0.76). Significantly diminished radiation dose and iodine load were observed in Group A compared with Group B (25.0%, 36.8% reduction; p = 0.007, 0.006, respectively). CONCLUSION The double-low protocol was feasible for pediatric abdominal CT and reduced both radiation dose and iodine load, while maintaining image quality.
Collapse
|
15
|
Optimizing Pulmonary Embolism Computed Tomography in the Age of Individualized Medicine: A Prospective Clinical Study. Invest Radiol 2019; 53:306-312. [PMID: 29438139 DOI: 10.1097/rli.0000000000000443] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE The aim of the study was to simultaneously optimize contrast media (CM) injection and scan parameters for the individual patient during computed tomography pulmonary angiography (CTPA). METHODS In this study (NCT02611115), 235 consecutive patients suspected of having pulmonary embolism were prospectively enrolled. Automated kV selection software on a third-generation multidetector computed tomography adapted tube voltage to the individual patient, based on scout scans. The contrast injection protocol was adapted to both patient body weight and kV-setting selection via a predefined formula, based on previous research. Injection data were collected from a contrast media and radiation dose monitoring software. Attenuation was measured in Hounsfield units (HU) in the pulmonary trunk (PT); attenuation values 200 HU or greater were considered diagnostic. Subjective image quality was assessed by using a 4-point Likert scale at the level of the PT, lobar, segmental, and subsegmental arteries. Results between groups were reported as mean ± SD. RESULTS Two hundred twenty-two patients (94%) were scanned at a kV setting below 100 kV: n = 108 for 70 kV, n = 82 for 80 kV, and n = 32 for 90 kV. Mean CM bolus volume (in milliliters) and total iodine load (in grams of iodine) for 70 to 90 kV were as follows: 24 ± 3 mL and 7 ± 1 g I, 29 ± 4 mL and 9 ± 2 g I, and 38 ± 4 mL and 11 ± 1 g I, respectively. Mean flow rates (in milliliters per second) and iodine delivery rates (in grams of iodine per second) were 3.0 ± 0.4 mL/s and 0.9 ± 0.1 g I/s (70 kV), 3.6 ± 0.4 mL/s and 1.0 ± 0.1 g I/s (80 kV), and 4.7 ± 0.5 mL/s and 1.3 ± 0.1 g I/s (90 kV). Mean radiation doses were 1.3 ± 0.3 mSv at 70 kV, 1.7 ± 0.4 mSv at 80 kV, and 2.2 ± 0.6 mSv at 90 kV. Mean vascular attenuation in the PT for each kV group was as follows: 397 ± 101 HU for 70 kV, 398 ± 96 HU for 80 kV, and 378 ± 100 HU for 90 kV, P = 0.59. Forty-six patients (21%) showed pulmonary embolism on the CTPA. One scan (90 kV) showed nondiagnostic segmental pulmonary arteries, and 5% of subsegmental arteries were of nondiagnostic image quality. All other segments were considered diagnostic-excellent subjective image quality. CONCLUSIONS Simultaneously optimizing both CM injections and kV settings to the individual patient in CTPA results in diagnostic attenuation with on average 24 to 38 mL of CM volume and a low radiation dose for most patients. This individualized protocol may help overcome attenuation-variation problems between patients and kV settings in CTPA.
Collapse
|
16
|
Aldosari S, Jansen S, Sun Z. Patient-specific 3D printed pulmonary artery model with simulation of peripheral pulmonary embolism for developing optimal computed tomography pulmonary angiography protocols. Quant Imaging Med Surg 2019; 9:75-85. [PMID: 30788248 PMCID: PMC6351806 DOI: 10.21037/qims.2018.10.13] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 10/26/2018] [Indexed: 11/06/2022]
Abstract
BACKGROUND Computed tomography pulmonary angiography (CTPA) is the preferred imaging modality for diagnosis of patients with suspected pulmonary embolism (PE). Radiation dose associated with CTPA has been significantly reduced due to the use of dose-reduction strategies, however, investigation of low-dose CTPA with use of different kVp and pitch values has not been systematically studied. The aim of this study was to utilize a 3D printed pulmonary model with simulation of small thrombus in the pulmonary arteries for development of optimal CTPA protocols. METHODS Animal blood clots were inserted into the pulmonary arteries to simulate peripheral embolism based on a realistic 3D printed pulmonary artery model. The 3D printed model was scanned with 192-slice 3rd generation dual-source CT with 1 mm slice thickness and 0.5 mm reconstruction interval. All images were reconstructed with advanced modelled iterative reconstruction (IR) at a strength level of 3. CTPA scanning parameters were as follows: 70, 80, 100 and 120 kVp, 0.9, 2.2 and 3.2 pitch values. Quantitative assessment of image quality was determined by measuring signal-to-noise ratio (SNR) in both main pulmonary arteries, while qualitative analysis of images was scored by two experienced radiologists (score of 1 indicates poor visualization of thrombus with no confidence, and score of 5 excellent visualization of thrombus with high confidence) to determine the image quality in relation to different scanning protocols for detection of thrombus in the pulmonary arteries. RESULTS No significant differences were found in SNR measurements among all CTPA protocols (P>0.05), regardless of kVp or pitch values used, although SNR was higher with 120 kVp and 0.9 and 2.2 pitch protocols than that in other protocols. The thrombi were detected in all images, with 70 kVp and 3.2 pitch protocol scored the lowest with a score of 3 by two observers, and images with other protocols were scored 4 or 5. Lowering kVp from 120 to 70 with use of high-pitch 2.2 or 3.2 protocol resulted in up to 80% dose reduction without significantly affecting image quality. CONCLUSIONS Low-dose CT pulmonary angiography protocols comprising 70 kVp and high pitch 2.2 or 3.2 allow for detection of peripheral PE with significant reduction in radiation dose while images are still considered diagnostic.
Collapse
Affiliation(s)
- Sultan Aldosari
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Australia
| | - Shirley Jansen
- Department of Vascular and Endovascular Surgery, Sir Charles Gairdner Hospital, Perth, Australia
- Curtin Medical School, Curtin University, Perth, Australia
- Faculty of Health and Medical Sciences, University of Western Australia, Crawley, Australia
- Heart and Vascular Research Institute, Harry Perkins Medical Research Institute, Perth, Australia
| | - Zhonghua Sun
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Australia
| |
Collapse
|
17
|
Aldosari S, Jansen S, Sun Z. Optimization of computed tomography pulmonary angiography protocols using 3D printed model with simulation of pulmonary embolism. Quant Imaging Med Surg 2019; 9:53-62. [PMID: 30788246 DOI: 10.21037/qims.2018.09.15] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background Three-dimensional (3D) printing has been shown to accurately replicate anatomical structures and pathologies in complex cardiovascular disease. Application of 3D printed models to simulate pulmonary arteries and pulmonary embolism (PE) could assist development of computed tomography pulmonary angiography (CTPA) protocols with low radiation dose, however, this has not been studied in the literature. The aim of this study was to investigate optimal CTPA protocols for detection of PE based on a 3D printed pulmonary model. Methods A patient-specific 3D printed pulmonary artery model was generated with thrombus placed in both main pulmonary arteries to represent PE. The model was scanned with 128-slice dual-source CT with slice thickness of 1 and 0.5 mm reconstruction interval. The tube voltage was selected to range from 70, 80, 100 to 120 kVp, and pitch value from 0.9 to 2.2 and 3.2. Quantitative assessment of image quality in terms of signal-to-noise ratio (SNR) was measured in the main pulmonary arteries and within the thrombus regions to determine the relationship between image quality and scanning protocols. Both two-dimensional (2D) and 3D virtual intravascular endoscopy (VIE) images were generated to demonstrate pulmonary artery and thrombus appearances. Results PE was successfully simulated in the 3D printed pulmonary artery model. There were no significant differences in SNR measured in the main pulmonary arteries with 100 and 120 kVp CTPA protocols (P>0.05), regardless of pitch value used. SNR was significantly lower in the high-pitch 3.2 protocols when compared to other protocols using 70 and 80 kVp (P<0.05). There were no significant differences in SNR measured within the thrombus among the 100 and 120 kVp protocols (P>0.05). For low dose 70 and 80 kVp protocols, SNR was significantly lower in the high-pitch of 3.2 protocols than that in other protocols with different pitch values (P<0.01). 2D images showed the pulmonary arteries and thrombus clearly, while 3D VIE demonstrated intraluminal appearances of pulmonary wall and thrombus in all protocols, except for the 70 kVp and pitch 3.2 protocol, with visualization of thrombus and pulmonary artery wall affected by artifact associated with high image noise. Radiation dose was reduced by up to 80% when lowering kVp from 120 to 100 and 80 kVp with use of 3.2 high-pitch protocol, without significantly affecting image quality. Conclusions Low-dose CT pulmonary angiography can be achieved with use of low kVp (80 and 100) and high-pitch protocol with significant reduction in radiation dose while maintaining diagnostic images of PE. Use of high pitch, 3.2 in 70 kVp protocol should be avoided due to high image noise and poorer quality.
Collapse
Affiliation(s)
- Sultan Aldosari
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Western Australia, Australia
| | - Shirley Jansen
- Department of Vascular and Endovascular Surgery, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia.,School of Public Health, Curtin University, Perth, Western Australia, Australia.,Faculty of Health and Medical Sciences, University of Western Australia, Crawley, Western Australia, Australia.,Heart and Vascular Research Institute, Harry Perkins Medical Research Institute, Perth, Western Australia, Australia
| | - Zhonghua Sun
- Discipline of Medical Radiation Sciences, School of Molecular and Life Sciences, Curtin University, Perth, Western Australia, Australia
| |
Collapse
|
18
|
Martin SS, van Assen M, Griffith LP, De Cecco CN, Varga-Szemes A, Bauer MJ, Wichmann JL, Vogl TJ, Schoepf UJ. Dual-Energy CT Pulmonary Angiography: Quantification of Disease Burden and Impact on Management. CURRENT RADIOLOGY REPORTS 2018. [DOI: 10.1007/s40134-018-0297-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
19
|
Tao SM, Li X, Schoepf UJ, Nance JW, Jacobs BE, Zhou CS, Gu HF, Lu MJ, Lu GM, Zhang LJ. Comparison of the effect of radiation exposure from dual-energy CT versus single-energy CT on double-strand breaks at CT pulmonary angiography. Eur J Radiol 2018; 101:92-96. [PMID: 29571808 DOI: 10.1016/j.ejrad.2018.02.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/19/2017] [Accepted: 02/03/2018] [Indexed: 11/19/2022]
Abstract
PURPOSE To compare the effect of dual-source dual-energy CT versus single-energy CT on DNA double-strand breaks (DSBs) in blood lymphocytes at CT pulmonary angiography (CTPA). METHODS AND MATERIALS Sixty-two patients underwent either dual-energy CTPA (Group 1: n = 21, 80/Sn140 kVp, 89/38 mAs; Group 2: n = 20, 100/Sn140 kVp, 89/76 mAs) or single-energy CTPA (Group 3: n = 21, 120 kVp, 110 mAs). Blood samples were obtained before and 5 min after CTPA. DSBs were assessed with fluorescence microscopy and Kruskal-Walls tests were used to compare DSBs levels among groups. Volume CT dose index (CTDIvol), dose length product (DLP) and organ radiation dose were compared using ANOVA. RESULTS There were increased excess DSB foci per lymphocyte 5 min after CTPA examinations in three groups (Group 1: P = .001; Group 2: P = .001; Group 3: P = .006). There were no differences among groups regarding excess DSB foci/cell and percentage of excess DSBs (Group 1, 23%; Group 2, 24%; Group 3, 20%; P = .932). CTDIvol, DLP and organ radiation dose in Group 1 were the lowest among the groups (all P < .001). CONCLUSION DSB is increased following dual-source and single-source CTPA, while dual-source dual-energy CT protocols do not increase the estimated radiation dose and also do not result in a higher incidence of DNA DSBs in patients undergoing CTPA.
Collapse
Affiliation(s)
- Shu Min Tao
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China
| | - Xie Li
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China
| | - U Joseph Schoepf
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China; Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Ashley River Tower, MSC 226, 25 Courtenay Dr. Charleston, SC 29401, United States
| | - John W Nance
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Ashley River Tower, MSC 226, 25 Courtenay Dr. Charleston, SC 29401, United States
| | - Brian E Jacobs
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Ashley River Tower, MSC 226, 25 Courtenay Dr. Charleston, SC 29401, United States
| | - Chang Sheng Zhou
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China
| | - Hai Feng Gu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China
| | - Meng Jie Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China
| | - Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.
| |
Collapse
|
20
|
Suntharalingam S, Allmendinger T, Blex S, Al-Bayati M, Nassenstein K, Schweiger B, Forsting M, Wetter A. Spectral Beam Shaping in Unenhanced Chest CT Examinations: A Phantom Study on Dose Reduction and Image Quality. Acad Radiol 2018; 25:153-158. [PMID: 29055683 DOI: 10.1016/j.acra.2017.08.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/12/2017] [Accepted: 08/21/2017] [Indexed: 10/18/2022]
Abstract
RATIONALE AND OBJECTIVES This study aimed to determine the optimal tube potential for unenhanced chest computed tomographies (CTs) with age-related phantoms. MATERIALS AND METHODS Three physical anthropomorphic phantoms (newborn, 5-year-old child, and adult) were scanned on a third-generation dual-source CT using CAREkV in semi-mode and CAREDose4D (ref. KV: 120; ref. mAs 50). Scans were performed with all available tube potentials (70-150 kV and Sn150 kV). The lowest volume computed tomography dose index (CTDIvol) was selected to perform additional Sn100-kV scans with matched and half (Sn100-half) CTDIvol value. Image quality was evaluated on the basis of contrast-to-noise ratio (CNR). RESULTS For the newborn phantom, 70-110 kV was selected as the optimal range (0.36-0.37 mGy). Using Sn150 kV led to an increase in radiation dose (0.75 mGy) without improving CNR (96.9 vs 101.5). Sn100-half showed a decrease in CNR (73.1 vs 101.5). The lowest CTDIvol for the child phantom was achieved between 100 and 120 kV (0.78-0.80 mGy). Using Sn150 kV increased radiation dose (1.02 mGy) without improvement of CNR (92.4 vs 95.8). At Sn100-half CNR was decreased (61.4 vs 95.8). For adults, 140 and 150 kV revealed the lowest CTDIvol (2.68 and 2.67 mGy). The Sn150 kV scan delivered comparable CNR (54.4 vs 56.6), but a lower CTDIvol (2.08 mGy). At Sn100-half CNR was comparable to the 150 kV scan (58.1 vs 56.6). CONCLUSION Unenhanced chest CT performed at 100 kV or 150 kV with tin filtration enables radiation dose reduction for the adult phantom, but not for the pediatric phantoms.
Collapse
|
21
|
Meyer M, Haubenreisser H, Schabel C, Leidecker C, Schmidt B, Schoenberg SO, Henzler T. CT pulmonary angiography in patients with acute or chronic renal insufficiency: Evaluation of a low dose contrast material protocol. Sci Rep 2018; 8:1995. [PMID: 29386532 PMCID: PMC5792433 DOI: 10.1038/s41598-018-20254-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 01/09/2018] [Indexed: 12/28/2022] Open
Abstract
Adverse effects of intravenous contrast media (CM) in patients with renal risk factors and acute kidney injury are still controversially discussed. The aim of this study was to investigate whether dual-energy (DE) pulmonary CT angiography (CTPA) in combination with a noise optimized virtual monoenergetic imaging algorithm allows for a reduction of CM. This IRB-approved study comprised 150 patients with suspected pulmonary embolism (78 male; mean age 65 ± 17years). 50 patients with acute/chronic renal failure were examined on a 3rd generation dual-source CT with an optimized DE CTPA protocol and a low CM injection protocol (5.4 g iodine). 100 further patients were either examined with a standard CTPA protocol or a standard DE CTPA (32 g iodine). For the DE CTPA virtual monoenergetic spectral datasets (40-100 keV) were reconstructed. Main pulmonary arteries at 50 keV and peripheral pulmonary arteries at 40 keV datasets provided the highest contrast-to-noise-ratio (CNR) for both the standard DE CTPA and the optimized protocol, with significantly higher CNR values for the standard DE CTPA protocol (p < 0.05). No pulmonary embolism was missed on the optimized CM protocol. DE CTPA utilizing image reconstruction at 40/50 keV allowed for a reduction of 84% in iodine load while maintaining CNR, which is especially important in patients with acute/chronic renal failure.
Collapse
Affiliation(s)
- Mathias Meyer
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Mannheim, Germany.
| | - Holger Haubenreisser
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Mannheim, Germany
| | - Christoph Schabel
- Department of Radiology, Duke University Medical Center, Durham, NC, United States
| | | | - Bernhard Schmidt
- Imaging & Therapy Division, Siemens Healthcare, Forchheim, Germany
| | - Stefan O Schoenberg
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Mannheim, Germany
| | - Thomas Henzler
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim - Heidelberg University, Mannheim, Germany
| |
Collapse
|
22
|
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
|
23
|
Hu X, Ma L, Zhang J, Li Z, Shen Y, Hu D. Use of pulmonary CT angiography with low tube voltage and low-iodine-concentration contrast agent to diagnose pulmonary embolism. Sci Rep 2017; 7:12741. [PMID: 29038563 PMCID: PMC5643383 DOI: 10.1038/s41598-017-13077-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 09/18/2017] [Indexed: 12/26/2022] Open
Abstract
Pulmonary CT angiography (CTPA) is regarded as the preferred imaging method in diagnosing pulmonary embolism (PE). Considering the harm of radiation exposure and the side effect of iodinated contrast agent, CTPA protocol with low tube voltage and low dose of contrast agent became research hotspot in last decade. The present study evaluates the image quality, radiation dose, positive rate of PE and the location of PE with a CTPA protocol using low tube voltage (80 kVp) and low-iodine-concentration contrast agent (270 mg I/ml) in patients suspected of PE compared to a conventional CTPA protocol (120 kVp, 350 mg I/ml). The results showed that 80 kVp CTPA protocol with 40 ml 270 mg I/ml achieved equally subjective image quality and a positive rate for diagnosing PE, though the quantitative image quality was reduced compared to the 120 kVp CTPA protocol with 40 ml 350 mg I/ml administered, with a 63.6% decrease in radiation dose and a 22.9% reduction in iodine content of contrast agent. Our results document that CTPA protocol with low tube voltage and low iodine concentration of contrast agent is satisfied to the clinical application.
Collapse
Affiliation(s)
- Xuemei Hu
- Department of Radiology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Liya Ma
- Department of Radiology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Jinhua Zhang
- Department of Radiology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Zhen Li
- Department of Radiology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Yaqi Shen
- Department of Radiology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China.
| | - Daoyu Hu
- Department of Radiology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
24
|
Nagayama Y, Nakaura T, Oda S, Tsuji A, Urata J, Furusawa M, Tanoue S, Utsunomiya D, Yamashita Y. Value of 100 kVp scan with sinogram-affirmed iterative reconstruction algorithm on a single-source CT system during whole-body CT for radiation and contrast medium dose reduction: an intra-individual feasibility study. Clin Radiol 2017; 73:217.e7-217.e16. [PMID: 29029768 DOI: 10.1016/j.crad.2017.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 07/04/2017] [Accepted: 09/12/2017] [Indexed: 01/28/2023]
Abstract
AIM To perform an intra-individual investigation of the usefulness of a contrast medium (CM) and radiation dose-reduction protocol using single-source computed tomography (CT) combined with 100 kVp and sinogram-affirmed iterative reconstruction (SAFIRE) for whole-body CT (WBCT; chest-abdomen-pelvis CT) in oncology patients. MATERIALS AND METHODS Forty-three oncology patients who had undergone WBCT under both 120 and 100 kVp protocols at different time points (mean interscan intervals: 98 days) were included retrospectively. The CM doses for the 120 and 100 kVp protocols were 600 and 480 mg iodine/kg, respectively; 120 kVp images were reconstructed with filtered back-projection (FBP), whereas 100 kVp images were reconstructed with FBP (100 kVp-F) and the SAFIRE (100 kVp-S). The size-specific dose estimate (SSDE), iodine load and image quality of each protocol were compared. RESULTS The SSDE and iodine load of 100 kVp protocol were 34% and 21%, respectively, lower than of 120 kVp protocol (SSDE: 10.6±1.1 versus 16.1±1.8 mGy; iodine load: 24.8±4versus 31.5±5.5 g iodine, p<0.01). Contrast enhancement, objective image noise, contrast-to-noise-ratio, and visual score of 100 kVp-S were similar to or better than of 120 kVp protocol. CONCLUSION Compared with the 120 kVp protocol, the combined use of 100 kVp and SAFIRE in WBCT for oncology assessment with an SSCT facilitated substantial reduction in the CM and radiation dose while maintaining image quality.
Collapse
Affiliation(s)
- Y Nagayama
- Department of Radiology, Kumamoto City Hospital 1-1-60, Koto, Higashi-ku, Kumamoto City, 862-0909, Japan; Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan.
| | - T Nakaura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - S Oda
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - A Tsuji
- Department of Radiology, Kumamoto City Hospital 1-1-60, Koto, Higashi-ku, Kumamoto City, 862-0909, Japan
| | - J Urata
- Department of Radiology, Kumamoto City Hospital 1-1-60, Koto, Higashi-ku, Kumamoto City, 862-0909, Japan
| | - M Furusawa
- Department of Radiology, Kumamoto City Hospital 1-1-60, Koto, Higashi-ku, Kumamoto City, 862-0909, Japan
| | - S Tanoue
- Department of Radiology, Kumamoto City Hospital 1-1-60, Koto, Higashi-ku, Kumamoto City, 862-0909, Japan; Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - D Utsunomiya
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| | - Y Yamashita
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto 860-8556, Japan
| |
Collapse
|
25
|
CT Angiography: Post-processed Contrast Enhancement for Improved Detection of Pulmonary Embolism. Acad Radiol 2017; 24:131-136. [PMID: 27863899 DOI: 10.1016/j.acra.2016.09.024] [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: 08/07/2016] [Revised: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 11/24/2022]
Abstract
RATIONALE AND OBJECTIVES The study aimed to improve the detection of pulmonary embolism via an iodine contrast enhancement tool in patients who underwent suboptimal enhanced computed tomography angiography (CTA). MATERIALS AND METHODS We evaluated the CT examinations of 41 patients who underwent CTA for evaluation of the pulmonary arteries which suffered from suboptimal contrast enhancement. The contrast enhancement of the reconstructed images was increased via a post-processing tool (vContrast). Image noise and contrast-to-noise ratio (CNR) were assessed in eight different regions: main pulmonary artery, right and left pulmonary arteries, right and left segment arteries, muscle, subcutaneous fat, and bone. For subjective image assessment, three experienced radiologists evaluated the diagnostic quality. RESULTS While employing the post-processing algorithm, the CNR for contrast-filled lumen and thrombus/muscle improves significantly by a factor of 1.7 (CNR without vContrast = 8.48 ± 6.79/CNR with vContrast = 14.46 ± 5.29) (P <0.01). No strengthening of artifacts occurred, and the mean Hounsfield unit values of the muscle, subcutaneous fat, and the bone showed no significant changes. Subjective image analysis illustrated a significant improvement using post-processing for clinically relevant criteria such as diagnostic confidence. CONCLUSIONS vContrast makes CT angiograms with inadequate contrast applicable for diagnostic evaluation, offering an improved visualization of the pulmonary arteries. In addition, vContrast can help in the significant reduction of the iodine contrast material.
Collapse
|
26
|
Li X, Chen GZ, Zhao YE, Schoepf UJ, Albrecht MH, Bickford MW, Gu HF, Zhang LJ, Lu GM. Radiation Optimized Dual-source Dual-energy Computed Tomography Pulmonary Angiography: Intra-individual and Inter-individual Comparison. Acad Radiol 2017; 24:13-21. [PMID: 27789203 DOI: 10.1016/j.acra.2016.09.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 09/11/2016] [Accepted: 09/14/2016] [Indexed: 11/28/2022]
Abstract
OBJECTIVES This study aimed to intra-individually and inter-individually compare image quality, radiation dose, and diagnostic accuracy of dual-source dual-energy computed tomography pulmonary angiography (CTPA) protocols in patients with suspected pulmonary embolism (PE). METHODS Thirty-three patients with suspected PE underwent initial and follow-up dual-energy CTPA at 80/Sn140 kVp (group A) or 100/Sn140 kVp (group B), which were assigned based on tube voltages. Subjective and objective CTPA image quality and lung perfusion map image quality were evaluated. Diagnostic accuracies of CTPA and perfusion maps were assessed by two radiologists independently. Effective dose (ED) was calculated and compared. RESULTS Mean computed tomography (CT) values of pulmonary arteries were higher in group A than group B (P = .006). There was no difference in signal-to-noise ratio and contrast-to-noise ratio between the two groups (both P > .05). Interobserver agreement for evaluating subjective image quality of CTPA and color-coded perfusion images was either good (κ = 0.784) or excellent (κ = 0.887). Perfusion defect scores and diagnostic accuracy of CTPA showed no difference between both groups (both P > .05). Effective dose of group A was reduced by 45.8% compared to group B (P < .001). CONCLUSIONS Second-generation dual-source dual-energy CTPA with 80/Sn140 kVp allows for sufficient image quality and diagnostic accuracy for detecting PE while substantially reducing radiation dose.
Collapse
Affiliation(s)
- Xie Li
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Guo Zhong Chen
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Yan E Zhao
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - U Joseph Schoepf
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China; Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina
| | - Moritz H Albrecht
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina
| | - Matthew W Bickford
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina
| | - Hai Feng Gu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China.
| | - Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, No. 305, Zhongshan East Road, Nanjing, Jiangsu, 210002, China.
| |
Collapse
|
27
|
State-of-the-Art Pulmonary CT Angiography for Acute Pulmonary Embolism. AJR Am J Roentgenol 2016; 208:495-504. [PMID: 27897042 DOI: 10.2214/ajr.16.17202] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Pulmonary CT angiography (CTA) is the imaging modality of choice in suspected acute pulmonary embolism (PE). Current pulmonary CTA techniques involve ever lower doses of contrast medium and radiation along with advanced postprocessing applications to enhance image quality, diagnostic accuracy, and provide added value in patient management. The objective of this article is to summarize these current developments and discuss the appropriate use of state-of-the-art pulmonary CTA. CONCLUSION Pulmonary CTA is well established as a fast and reliable means of excluding or diagnosing PE. Continued developments in CT system hardware and postprocessing techniques will allow incremental reductions in radiation and contrast material requirements while improving image quality. Advances in risk stratification and prognostication from pulmonary CTA examinations should further refine its clinical value while minimizing the potential harm from overutilization and overdiagnosis.
Collapse
|
28
|
Martini K, Meier A, Higashigaito K, Saltybaeva N, Alkadhi H, Frauenfelder T. Prospective Randomized Comparison of High-pitch CT at 80 kVp Under Free Breathing with Standard-pitch CT at 100 kVp Under Breath-Hold for Detection of Pulmonary Embolism. Acad Radiol 2016; 23:1335-1341. [PMID: 27639625 DOI: 10.1016/j.acra.2016.07.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 12/11/2022]
Abstract
RATIONALE AND OBJECTIVES To prospectively compare high-pitch computed tomography (HPCT) under free breathing (FB) with standard-pitch CT (SPCT) under breath-hold (BH) for detection of pulmonary embolism (PE). MATERIALS AND METHODS One hundred consecutive patients (47 females; mean age 58.7 ± 16.6) randomly underwent HPCT-FB (n = 50) or SPCT-BH (n = 50). Radiation doses were documented. One reader measured pulmonary artery attenuation and noise; mean signal-to-noise ratio (SNR) was calculated. Two readers assessed image quality, diagnostic confidence for detection of PE, motion artifacts, assessability of anatomical structures, and presence of transient interruption of contrast as sign of Valsalva maneuver. Inter-reader agreement was calculated. RESULTS Radiation dose was significantly lower in HPCT compared to SPCT (2.68 ± 0.60 mGy vs 6.01 ± 2.26 mGy; P < .001). Mean pulmonary artery attenuation and image noise were significantly higher in HPCT (attenuation: 479 Hounsfield unit (HU) vs 343HU; P < .001; noise: 16 HU vs 10 HU; P < .001) whereas SNR was similar between groups (34 HU vs 38 HU; P = .258). HPCT had significantly higher diagnostic confidence for PE detection (P = .048), less cardiac and breathing artifacts (P < .001), better assessability of anatomical structures, and fewer cases of transient interruption of contrast (P < .001) compared to the SPCT. CONCLUSIONS HPCT-FB allows for a significant reduction of breathing and motion artifacts compared to SPCT-BH. Diagnostic confidence, assessability of vascular and bronchial structures, as well as SNR are maintained.
Collapse
Affiliation(s)
- K Martini
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091 Zürich, Switzerland.
| | - A Meier
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091 Zürich, Switzerland
| | - K Higashigaito
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091 Zürich, Switzerland
| | - N Saltybaeva
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091 Zürich, Switzerland
| | - H Alkadhi
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091 Zürich, Switzerland
| | - T Frauenfelder
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, CH-8091 Zürich, Switzerland
| |
Collapse
|
29
|
Boos J, Kröpil P, Lanzman RS, Aissa J, Schleich C, Heusch P, Sawicki LM, Antoch G, Thomas C. CT pulmonary angiography: simultaneous low-pitch dual-source acquisition mode with 70 kVp and 40 ml of contrast medium and comparison with high-pitch spiral dual-source acquisition with automated tube potential selection. Br J Radiol 2016; 89:20151059. [PMID: 27007972 DOI: 10.1259/bjr.20151059] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To assess the feasibility of a 70-kVp CT pulmonary angiography (CTPA) protocol using simultaneous dual-source (SimDS) acquisition mode with 40 ml of contrast medium (CM) and comparison with a high-pitch spiral dual-source (SpiralDS) acquisition protocol with automated tube potential selection (ATPS). METHODS Following the introduction of a new 70-kVp/40-ml SimDS-CTPA protocol in December 2014 for all patients with a body mass index (BMI) below 35 kg m(-2), the first 35 patients were retrospectively included in this study and assigned to Group A (BMI: 27 ± 4 kg m(-2), age: 66 ± 15 years). The last 35 patients with a BMI below 35 kg m(-2) who had received SpiralDS-CTPA with ATPS were included for comparison (Group B) (70 ml CM; BMI: 27 ± 4 kg m(-2), age: 68 ± 16 years). Subjective image quality (image quality) was assessed by two radiologists (from 1, non-diagnostic, to 4, excellent). Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), volumetric CT dose index (CTDIvol), dose-length product (DLP) and effective dose were assessed. RESULTS All examinations were of diagnostic image quality. Subjective image quality, SNR and CNR were comparable between Groups A and B (3.7 ± 0.6 vs 3.7 ± 0.5, 14.6 ± 6.0 vs 13.9 ± 3.7 and 12.4 ± 5.7 vs 11.6 ± 3.3, respectively; p > 0.05). CTDIvol, DLP and effective dose were significantly lower in Group A than in Group B (4.5 ± 1.6 vs 7.5 ± 2.1 mGy, 143.3 ± 44.8 vs 278.3 ± 79.44 mGy cm and 2.0 ± 0.6 vs 3.9 ± 1.1 mSv, respectively; p < 0.05). CONCLUSION 70-kVp SimDS-CTPA with 40 ml of CM is feasible and provides diagnostic image quality, while radiation dose and CM can be reduced by almost 50% and 40%, respectively, compared with a SpiralDS-CTPA protocol with ATPS. ADVANCES IN KNOWLEDGE 70-kVp SimDS-CTPA with 40 ml of CM is feasible in patients with a BMI up to 35 kg m(-2) and can help reduce radiation exposure and CM in these patients.
Collapse
Affiliation(s)
- Johannes Boos
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Patric Kröpil
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Rotem S Lanzman
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Joel Aissa
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Christoph Schleich
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Philipp Heusch
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Lino M Sawicki
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Gerald Antoch
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| | - Christoph Thomas
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Dusseldorf, Dusseldorf, Germany
| |
Collapse
|