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Assessment of Imaging Protocol and Patients Radiation Exposure in Computed Tomography Colonography. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11114761] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the screening and identifying of colon and rectum malignancy, computed tomography colonography (CTC) is a highly effective imaging technique, albeit patients receiving a significant effective dose. Accordingly, patient dose evaluation is an important need, seeking to ensure benefits outweigh the projected cancer risk. Objective: For CTC procedures carried out in the Radiology Department, Medical Imaging Operation Services, King Fahad Medical City (KFMC), evaluation is done using the current American College of Radiology (ACR) imaging protocol and concomitant patient-effective doses. Study is carried out on a sample size of 55 CTC procedures, involving 25 males (45%) and 30 females (55%). The patients were classified as follows: two groups based on CT machine; four groups based on the applied protocol; and three groups based on the procedure results. All procedures were carried out using two machines, the products of two different vendors (a GE Healthcare DISCOVERY CT 750 HD 64 slices dual-energy scanner and a Philips Brilliance CT 64 slices scanner). The overall mean, standard deviation (SD), median, and range of the effective dose (in mSv) were 11.57 ± 7.75, 9.25 (2.17–31.93). Automatic tube current modulation (ATCM) shows a significant increase in CTDIvol up to 69% and effective dose (mSv) up to 95% than the manual tube current (mA) compared to the standard protocol. The CT protocol variation results in a three-fold variation in patient-effective dose. The technologist role is crucial in selecting a noise reference based on patient weight and adjusting tube current per slice to avoid overexposure during ATCM protocol.
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Liu JJ, Xue HD, Liu W, Yan J, Pan WD, Li B, Xu K, Wang Y, Li P, Xiao Y, Jin ZY. CT colonography with spectral filtration and advanced modeled iterative reconstruction in the third-generation dual-source CT: image quality, radiation dose and performance in clinical utility. Acad Radiol 2021; 28:e127-e136. [PMID: 32434689 DOI: 10.1016/j.acra.2020.03.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 03/17/2020] [Accepted: 03/18/2020] [Indexed: 12/23/2022]
Abstract
RATIONALE AND OBJECTIVES To evaluate image quality, radiation dose and its diagnostic performance in clinical utility of CT colonography (CTC) applying spectral filtration and advanced modeled iterative reconstruction (ADMIRE) techniques in third-generation dual-source CT. MATERIALS AND METHODS A total of 125 patients for screening or diagnostic purposes underwent CTC at 120kVp standard dose (120kVp-STD) with filtered-back projection reconstruction (FBP) in supine position, then at a tin-filtered 150 kVp low dose (Sn150kVp-LD) and a tin-filtered 100 kVp ultra-low dose (Sn100kVp-ULD) with ADMIRE reconstruction in prone position. Radiation metrics were recorded. Objective and subjective image qualities were compared, and the diagnostic performance was assessed for both colonic and extracolonic findings using CTC reporting and data system (C-RADS). RESULTS The effective dose was significantly lower for Sn150kVp-LD and Sn100kVp-ULD than 120kVp-STD protocol, resulting in 22.5% and 87.5% reductions (1.55±0.30 and 0.25±0.07 mSv vs. 2.00±0.52 mSv; both p<0.01), respectively. Image noise and signal-to-noise ratio were improved significantly for Sn150kVp-LD with ADMIRE compared with 120kVp-STD, both of which had similar excellent 2D and 3D subjective image quality with equivalent diagnostic performance. Sn100kVp-ULD with ADMIRE had decreased subjective image quality and significant different C-RADS extracolonic-score (E-score) compared with 120kVp-STD, however, C-RADS colonic-score (C-score) of that showed no significantly difference. CONCLUSION Sn150kVp and Sn100kVp with ADMIRE reconstruction provide an alternative low dose CTC strategy and could be feasible in clinical screening or diagnostic scenarios.
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Affiliation(s)
- Jing-Juan Liu
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Hua-Dan Xue
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Wei Liu
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China.
| | - Jing Yan
- Siemens Medical System, 201318, Shanghai, China
| | - Wei-Dong Pan
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Bin Li
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Kai Xu
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Yun Wang
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Ping Li
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Yi Xiao
- Department of General Surgery, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
| | - Zheng-Yu Jin
- Department of Radiology, Peking Union Medical College Hospital, Shuaifuyuan No. 1, Dongcheng District, 100730, Beijing, China
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Popic J, Tipuric S, Balen I, Mrzljak A. Computed tomography colonography and radiation risk: How low can we go? World J Gastrointest Endosc 2021; 13:72-81. [PMID: 33763187 PMCID: PMC7958467 DOI: 10.4253/wjge.v13.i3.72] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 01/23/2021] [Accepted: 02/19/2021] [Indexed: 02/06/2023] Open
Abstract
Computed tomography colonography (CTC) has become a key examination in detecting colonic polyps and colorectal carcinoma (CRC). It is particularly useful after incomplete optical colonoscopy (OC) for patients with sedation risks and patients anxious about the risks or potential discomfort associated with OC. CTC's main advantages compared with OC are its non-invasive nature, better patient compliance, and the ability to assess the extracolonic disease. Despite these advantages, ionizing radiation remains the most significant burden of CTC. This opinion review comprehensively addresses the radiation risk of CTC, incorporating imaging technology refinements such as automatic tube current modulation, filtered back projections, lowering the tube voltage, and iterative reconstructions as tools for optimizing low and ultra-low dose protocols of CTC. Future perspectives arise from integrating artificial intelligence in computed tomography machines for the screening of CRC.
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Affiliation(s)
- Jelena Popic
- Department of Radiology, University Hospital Merkur, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Sandra Tipuric
- Department of Family Medicine, Health Center Zagreb-East, Zagreb 10000, Croatia
| | - Ivan Balen
- Department of Gastroenterology and Endocrinology, General Hospital Slavonski brod “Dr. Josip Bencevic”, Slavonski Brod 35000, Croatia
| | - Anna Mrzljak
- Department of Medicine, Merkur University Hospital, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
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Cianci R, Delli Pizzi A, Esposito G, Timpani M, Tavoletta A, Pulsone P, Basilico R, Cotroneo AR, Filippone A. Ultra-low dose CT colonography with automatic tube current modulation and sinogram-affirmed iterative reconstruction: Effects on radiation exposure and image quality. J Appl Clin Med Phys 2018; 20:321-330. [PMID: 30586479 PMCID: PMC6333183 DOI: 10.1002/acm2.12510] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 11/03/2018] [Accepted: 11/20/2018] [Indexed: 12/14/2022] Open
Abstract
Objective To assess the radiation dose and image quality of ultra‐low dose (ULD)‐CT colonography (CTC) obtained with the combined use of automatic tube current (mAs) modulation with a quality reference mAs of 25 and sinogram‐affirmed iterative reconstruction (SAFIRE), compared to low‐dose (LD) CTC acquired with a quality reference mAs of 55 and reconstructed with filtered back projection (FBP). Methods Eighty‐two patients underwent ULD‐CTC acquisition in prone position and LD‐CTC acquisition in supine position. Both ULD‐CTC and LD‐CTC protocols were compared in terms of radiation dose [weighted volume computed tomography dose index (CTDIvol) and effective dose], image noise, image quality, and polyp detection. Results The mean effective dose of ULD‐CTC was significantly lower than that of LD‐CTC (0.98 and 2.69 mSv respectively, P < 0.0001) with an overall dose reduction of 63.2%. Image noise was comparable between ULD‐CTC and LD‐CTC (28.6 and 29.8 respectively, P = 0.09). There was no relevant difference when comparing image quality scores and polyp detection for both 2D and 3D images. Conclusion ULD‐CTC allows to significantly reduce the radiation dose without meaningful image quality degradation compared to LD‐CTC.
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Affiliation(s)
- Roberta Cianci
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Andrea Delli Pizzi
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Gianluigi Esposito
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Mauro Timpani
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Alessandra Tavoletta
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Pierluigi Pulsone
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Raffaella Basilico
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Antonio Raffaele Cotroneo
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
| | - Antonella Filippone
- Department of Neuroscience Imaging and Clinical Sciences, University "G. d'Annunzio", SS. Annunziata Hospital, Chieti, Italy
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Virtual Computed Tomography Colonography: Evaluation of 2D and Virtual 3D Image Quality of Sub-mSv Examinations Enabled by Third-generation Dual Source Scanner Featuring Tin Filtering. Acad Radiol 2018; 25:1046-1051. [PMID: 29371121 DOI: 10.1016/j.acra.2017.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 12/04/2017] [Accepted: 12/17/2017] [Indexed: 12/12/2022]
Abstract
RATIONALE AND OBJECTIVES To evaluate two- and three-dimensional (2D and 3D) image quality of sub-milliSievert (mSv) computed tomography (CT) colonography utilizing a third-generation dual source CT scanner featuring a tin filter. METHODS We retrospectively evaluated 26 consecutive patients who underwent third-generation dual source CT colonography, nine with the standard-dose clinical-scan protocol (SDP) and 17 with a low-dose protocol (LDP) featuring a tin filter. Radiation dose was evaluated by volume computed tomography dose index (CTDIvol), dose length product (DLP), effective dose (E), and size-specific dose estimate. Objective image quality was evaluated utilizing signal-to-noise ratio (SNR) derived from standardized placed regions of interest on the transverse 2D images and the ratio of SNR/CTDIvol (normalized SNR). Two radiologists in consensus assessed subjective image quality of the virtual 3D images. RESULTS There were no significant differences in subjective image quality (P = .661). All examinations were rated "excellent" or "good" for diagnostic confidence. The mean total for DLP/E was 143.4 ± 29.8 mGy/3.00 ± 0.40 mSv in the SDP and therefore significantly higher than in the LDP with 36.9 ± 8.7 mGy/0.75 ± 0.16 mSv (P < .001). The SNR was 8.9 ± 2.1 in the SDP and 4.9 ± 0.8 in the LDP. CONCLUSIONS Third-generation dual source CT featuring a tin filter enables consistent sub-mSv colonography without substantially impairing image quality.
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Obaro AE, Burling DN, Plumb AA. Colon cancer screening with CT colonography: logistics, cost-effectiveness, efficiency and progress. Br J Radiol 2018; 91:20180307. [PMID: 29927637 DOI: 10.1259/bjr.20180307] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Colorectal cancer (CRC) incidence and mortality can be significantly reduced by population screening. Several different screening methods are currently in use, and this review focuses specifically on the imaging technique computed tomographic colonography (CTC). The challenges and logistics of CTC screening, as well as the importance of test accuracy, uptake, quality assurance and cost-effectiveness will be discussed. With comparable advanced adenoma detection rates to colonoscopy (the most commonly used whole-colon investigation), CTC is a less-invasive alternative, requiring less laxative, and with the potential benefit that it permits assessment of extra colonic structures. Three large-scale European trials have contributed valuable evidence supporting the use of CTC in population screening, and highlight the importance of selecting appropriate clinical management pathways based on initial CTC findings. Future research into CTC-screening will likely focus on radiologist training and CTC quality assurance, with identification of evidence-based key performance indicators that are associated with clinically-relevant outcomes such as the incidence of post-test interval cancers (CRC occurring after a presumed negative CTC). In comparison to other CRC screening techniques, CTC offers a safe and accurate option that is particularly useful when colonoscopy is contraindicated. Forthcoming cost-effectiveness analyses which evaluate referral thresholds, the impact of extra-colonic findings and real-world uptake will provide useful information regarding the feasibility of future CTC population screening.
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Affiliation(s)
- Anu E Obaro
- 1 Centre for Medical Imaging, University College London , London , UK.,2 St Mark's Academic Institute, St Mark's Hospital , Harrow , UK
| | - David N Burling
- 2 St Mark's Academic Institute, St Mark's Hospital , Harrow , UK
| | - Andrew A Plumb
- 1 Centre for Medical Imaging, University College London , London , UK
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Abstract
CT colonography (CTC) has demonstrated equivalent accuracy to optical colonoscopy in the detection of clinically relevant polyps and tumors but this is only possible when technique is optimized. The two most important features of a high-quality CTC are a well-prepared colon and a distended colon. This article will discuss the dietary, bowel preparation, and fecal/fluid tagging options to best prepare the colon. Strategies to optimally distend the colon will also be discussed. CT scan techniques including patient positioning and radiation dose optimization will be reviewed. With proper technique which includes sufficient bowel preparation, fecal/fluid tagging, bowel distension, and optimized scan technique, high-quality CTC examinations should become more feasible, easier to interpret, and more consistently reproducible leading to increased utilization and increased referrals.
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Yee J, McFarland E. Extracolonic findings and radiation at CT colonography: what the referring provider needs to know. Abdom Radiol (NY) 2018; 43:554-565. [PMID: 29450613 DOI: 10.1007/s00261-018-1461-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A better understanding of the risks and benefits of extracolonic findings and radiation dose will aid in the safe and proper implementation of CT colonography in clinical practice. The majority of extracolonic findings in screening patients are benign and can be ignored by referring physicians. Radiologists also need to be responsible in reporting extracolonic findings. Referring providers must be knowledgeable about the theoretic risks and controversies regarding the use of ionizing radiation. Screening CT colonography imparts a low-level of radiation to patients that is equivalent or less than annual background dose.
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Affiliation(s)
- Judy Yee
- Department of Radiology, Albert Einstein College of Medicine, Montefiore Medical Center, 111 East 210th St, Bronx, NY, 10467, USA.
| | - Elizabeth McFarland
- SSM St. Joseph Health Center, 300 Capitol Drive, St. Charles, MO, 63301, USA
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Vasan V, Brewington C. The Role of CT Colonography as a Screening Tool for Colorectal Cancer. CURRENT COLORECTAL CANCER REPORTS 2017. [DOI: 10.1007/s11888-017-0378-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Pooler BD, Lubner MG, Kim DH, Chen OT, Li K, Chen GH, Pickhardt PJ. Prospective Evaluation of Reduced Dose Computed Tomography for the Detection of Low-Contrast Liver Lesions: Direct Comparison with Concurrent Standard Dose Imaging. Eur Radiol 2016; 27:2055-2066. [PMID: 27595834 DOI: 10.1007/s00330-016-4571-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 08/08/2016] [Accepted: 08/22/2016] [Indexed: 12/22/2022]
Abstract
OBJECTIVES To prospectively compare the diagnostic performance of reduced-dose (RD) contrast-enhanced CT (CECT) with standard-dose (SD) CECT for detection of low-contrast liver lesions. METHODS Seventy adults with non-liver primary malignancies underwent abdominal SD-CECT immediately followed by RD-CECT, aggressively targeted at 60-70 % dose reduction. SD series were reconstructed using FBP. RD series were reconstructed with FBP, ASIR, and MBIR (Veo). Three readers-blinded to clinical history and comparison studies-reviewed all series, identifying liver lesions ≥4 mm. Non-blinded review by two experienced abdominal radiologists-assessing SD against available clinical and radiologic information-established the reference standard. RESULTS RD-CECT mean effective dose was 2.01 ± 1.36 mSv (median, 1.71), a 64.1 ± 8.8 % reduction. Pooled per-patient performance data were (sensitivity/specificity/PPV/NPV/accuracy) 0.91/0.78/0.60/0.96/0.81 for SD-FBP compared with RD-FBP 0.79/0.75/0.54/0.91/0.76; RD-ASIR 0.84/0.75/0.56/0.93/0.78; and RD-MBIR 0.84/0.68/0.49/0.92/0.72. ROC AUC values were 0.896/0.834/0.858/0.854 for SD-FBP/RD-FBP/RD-ASIR/RD-MBIR, respectively. RD-FBP (P = 0.002) and RD-MBIR (P = 0.032) AUCs were significantly lower than those of SD-FBP; RD-ASIR was not (P = 0.052). Reader confidence was lower for all RD series (P < 0.001) compared with SD-FBP, especially when calling patients entirely negative. CONCLUSIONS Aggressive CT dose reduction resulted in inferior diagnostic performance and reader confidence for detection of low-contrast liver lesions compared to SD. Relative to RD-ASIR, RD-FBP showed decreased sensitivity and RD-MBIR showed decreased specificity. KEY POINTS • Reduced-dose CECT demonstrates inferior diagnostic performance for detecting low-contrast liver lesions. • Reader confidence is lower with reduced-dose CECT compared to standard-dose CECT. • Overly aggressive dose reduction may result in misdiagnosis, regardless of reconstruction algorithm. • Careful consideration of perceived risks versus benefits of dose reduction is crucial.
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Affiliation(s)
- B Dustin Pooler
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA
| | - Meghan G Lubner
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA
| | - David H Kim
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA
| | - Oliver T Chen
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA
| | - Ke Li
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA.,Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA
| | - Guang-Hong Chen
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA.,Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA
| | - Perry J Pickhardt
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA. .,Department of Radiology, University of Wisconsin School of Medicine & Public Health, E3/311 Clinical Science Center, 600 Highland Ave., Madison, WI, 53792-3252, USA.
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Lambert L, Ourednicek P, Briza J, Giepmans W, Jahoda J, Hruska L, Danes J. Sub-milliSievert ultralow-dose CT colonography with iterative model reconstruction technique. PeerJ 2016; 4:e1883. [PMID: 27069813 PMCID: PMC4824919 DOI: 10.7717/peerj.1883] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/12/2016] [Indexed: 12/14/2022] Open
Abstract
Purpose. The purpose of this study was to evaluate the technical and diagnostic performance of sub-milliSievert ultralow-dose (ULD) CT colonograpy (CTC) in the detection of colonic and extracolonic lesions. Materials and Methods. CTC with standard dose (SD) and ULD acquisitions of 64 matched patients, half of them with colonic findings, were reconstructed with filtered back projection (FBP), hybrid (HIR) and iterative model reconstruction techniques (IMR). Image noise in six colonic segments, in the left psoas muscle and aorta were measured. Image quality of the left adrenal gland and of the colon in the endoscopic and 2D view was rated on a five point Likert scale by two observers, who also completed the reading of CTC for colonic and extracolonic findings. Results. The mean radiation dose estimate was 4.1 ± 1.4 mSv for SD and 0.86 ± 0.17 mSv for ULD for both positions (p < 0.0001). In ULD-IMR, SD-IMR and SD-HIR, the endoluminal noise was decreased in all colonic segments compared to SD-FBP (p < 0.001). There were 27 small (6–9 mm) and 17 large (≥10 mm) colonic lesions that were classified as sessile polyps (n = 38), flat lesions (n = 3), or as a mass (n = 3). Per patient sensitivity and specificity were 0.82 and 0.93 for ULD-FBP, 0.97 and 0.97 for ULD-HIR, 0.97 and 1.0 for ULD-IMR. Per polyp sensitivity was 0.84 for ULD-FBP, 0.98 for ULD-HIR, 0.98 for ULD-IMR. Significantly less extracolonic findings were detected in ULD-FBP and ULD-HIR, but in the E4 category by C-RADS (potentially important findings), the detection was similar. Conclusion. Both HIR and IMR are suitable for sub-milliSievert ULD CTC without sacrificing diagnostic performance of the study.
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Affiliation(s)
- Lukas Lambert
- Department of Radiology, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague , Prague , Czech Republic
| | - Petr Ourednicek
- Department of Imaging Methods, St. Anne's University Hospital in Brno , Brno , Czech Republic
| | - Jan Briza
- First Department of Surgery, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague , Prague , Czech Republic
| | - Walter Giepmans
- Clinical Science & Application Computed Tomography, Philips Healthcare , Best , The Netherlands
| | - Jiri Jahoda
- Department of Radiology, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague , Prague , Czech Republic
| | - Lukas Hruska
- Department of Imaging Methods, St. Anne's University Hospital in Brno , Brno , Czech Republic
| | - Jan Danes
- Department of Radiology, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague , Prague , Czech Republic
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12
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Yamamura S, Oda S, Imuta M, Utsunomiya D, Yoshida M, Namimoto T, Yuki H, Kidoh M, Funama Y, Baba H, Yamashita Y. Reducing the Radiation Dose for CT Colonography: Effect of Low Tube Voltage and Iterative Reconstruction. Acad Radiol 2016; 23:155-62. [PMID: 25872861 DOI: 10.1016/j.acra.2015.03.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Revised: 02/27/2015] [Accepted: 03/08/2015] [Indexed: 12/17/2022]
Abstract
RATIONALE AND OBJECTIVES The purpose of this study was to assess the effect of a low-tube-voltage technique and iterative reconstruction (IR) on the radiation dose and image quality of computed tomography colonography (CTC). MATERIALS AND METHODS We studied 30 patients (14 women and 16 men; mean age, 64.5 ± 13.1 years; range, 39-90 years) with colorectal cancer referred for surgical treatment. All underwent CTC with fecal tagging under a standard 120-kVp protocol in the supine position and a 100-kVp protocol in the prone position. The 120-kVp images were reconstructed with filtered back projection (FBP). The 100-kVp images were postprocessed using FBP and a hybrid type of IR (adaptive iterative dose reduction 3D). The effective radiation dose (ED), image noise, and contrast-to-noise ratio (CNR) were compared among the three protocols. The visual image quality was scored on a four-point scale. RESULTS The mean ED was significantly lower under the 100-kVp protocol than the 120-kVp protocol, resulting in a 27% radiation dose decrease (3.5 ± 2.0 vs 2.5 ± 1.5 mSv; P < .01). Image noise decreased by 48%, and the mean attenuation of tagged fluid increased from 452 to 558 HU on images acquired at 100 kVp with IR compared to that in the 120-kVp protocol; these differences were significant. The mean CNR was significantly higher under the 100 kVp with IR than the other two protocols. We found no significant differences in the visual scores for diagnostic utility between the 100 kVp with IR and the 120 kVp with FBP protocol (P = .10). CONCLUSIONS Low-tube-voltage CTC reduced the radiation dose by approximately 27% while maintaining the image quality.
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Chang K, Heisler M, Mahesh M, Baird G, Mayo-Smith W. CT colonography at low tube potential: using iterative reconstruction to decrease noise. Clin Radiol 2015; 70:981-8. [DOI: 10.1016/j.crad.2015.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 03/24/2015] [Accepted: 05/12/2015] [Indexed: 01/15/2023]
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14
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Patel JD, Chang KJ. The role of virtual colonoscopy in colorectal screening. Clin Imaging 2015; 40:315-20. [PMID: 26298421 DOI: 10.1016/j.clinimag.2015.07.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 07/06/2015] [Indexed: 02/07/2023]
Abstract
Colorectal cancer is the second leading cause of cancer-related deaths in the United States. The earlier colorectal cancer is detected, the better chance a person has of surviving 5 years after being diagnosed, emphasizing the need for effective and regular colorectal screening. Computed tomographic colonography has repeatedly demonstrated sensitivities equivalent to the current gold standard, optical colonoscopy, in the detection of clinically relevant polyps. It is an accurate, safe, affordable, available, reproducible, quick, and cost-effective option for colorectal screening and should be considered for mass screening.
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Affiliation(s)
- Jay D Patel
- Department of Diagnostic Imaging, The Warren Alpert Medical School of Brown University/Rhode Island Hospital, 593 Eddy St., Providence, RI 02903.
| | - Kevin J Chang
- Director of CT Colonography, Division of Body Imaging, Department of Diagnostic Imaging, The Warren Alpert Medical School of Brown University/Rhode Island Hospital, 593 Eddy St., Providence, RI 02908.
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Lambert L, Danes J, Jahoda J, Masek M, Lisy J, Ourednicek P. Submilisievert ultralow-dose CT colonography using iterative reconstruction technique: a feasibility study. Acta Radiol 2015; 56:517-25. [PMID: 24855290 DOI: 10.1177/0284185114533683] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 04/08/2014] [Indexed: 12/24/2022]
Abstract
BACKGROUND Computed tomography (CT) colonography is a well established modality for the examination of symptomatic patients as well as in screening. Recent technical advances in improving image quality by iterative reconstruction contribute to the reduction of the radiation dose which is a major concern in CT imaging. PURPOSE To evaluate image quality of ultralow-dose submilisievert CT colonography using hybrid iterative reconstruction technique. MATERIAL AND METHODS Sixteen patients underwent contrast-enhanced CT colonography with standard protocol in supine position and ultralow-dose protocol in prone position. Ultralow-dose datasets were reconstructed with filtered back projection and an advanced hybrid iterative reconstruction technique. Two radiologists independently evaluated 96 colonic segments for image quality in the endoluminal view and axial thin sections. Colonic distension, smoothness of colonic wall and distortion of folds in the endoluminal view, sharpness of colonic wall delineation, perceived image noise, and presence of photon starvation artifact were rated on a five-point scale. Intraluminal noise expressed as standard deviation of Hounsfield density was measured in all segments. RESULTS The mean radiation dose was 0.42 mSv and 5.48 mSv in prone and supine scans, respectively. All distended segments were rated evaluable in standard dose and ultralow-dose series reconstructed with the iterative reconstruction technique, whereas in 61% segments image quality was rated poor or unacceptable in ultralow-dose series where filtered back projection was used with worst ratings in the rectum and the sigmoid colon. CONCLUSION This pilot study shows that iterative reconstruction technique is a feasible method to decrease the radiation dose from CT colonography for both positions below 1mSv. Further investigations of larger scale need to be done to clarify, whether such a low radiation dose would influence the detection of polyps.
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Affiliation(s)
- Lukas Lambert
- Department of Radiology, First Faculty of Medicine of Charles University, Prague, Czech Republic
| | - Jan Danes
- Department of Radiology, First Faculty of Medicine of Charles University, Prague, Czech Republic
| | - Jiri Jahoda
- Department of Radiology, First Faculty of Medicine of Charles University, Prague, Czech Republic
| | - Martin Masek
- Department of Radiology, First Faculty of Medicine of Charles University, Prague, Czech Republic
| | - Jiri Lisy
- Department of Radiology, 2nd Faculty of Medicine of Charles University and Motol University Hospital, Prague, Czech Republic
| | - Petr Ourednicek
- Department of Imaging Methods, St. Anne’s University Hospital, Brno, Czech Republic
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Lubner MG, Pooler BD, Kitchin DR, Tang J, Li K, Kim DH, Munoz del Rio A, Chen GH, Pickhardt PJ. Sub-milliSievert (sub-mSv) CT colonography: a prospective comparison of image quality and polyp conspicuity at reduced-dose versus standard-dose imaging. Eur Radiol 2015; 25:2089-102. [PMID: 25903700 DOI: 10.1007/s00330-015-3603-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 01/09/2015] [Accepted: 01/15/2015] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To prospectively compare reduced-dose (RD) CT colonography (CTC) with standard-dose (SD) imaging using several reconstruction algorithms. METHODS Following SD supine CTC, 40 patients (mean age, 57.3 years; 17 M/23 F; mean BMI, 27.2) underwent an additional RD supine examination (targeted dose reduction, 70-90%). DLP, CTDI(vol), effective dose, and SSDE were compared. Several reconstruction algorithms were applied to RD series. SD-FBP served as reference standard. Objective image noise, subjective image quality and polyp conspicuity were assessed. RESULTS Mean CTDI(vol) and effective dose for RD series was 0.89 mGy (median 0.65) and 0.6 mSv (median 0.44), compared with 3.8 mGy (median 3.1) and 2.8 mSv (median 2.3) for SD series, respectively. Mean dose reduction was 78%. Mean image noise was significantly reduced on RD-PICCS (24.3 ± 19HU) and RD-MBIR (19 ± 18HU) compared with RD-FBP (90 ± 33), RD-ASIR (72 ± 27) and SD-FBP (47 ± 14 HU). 2D image quality score was higher with RD-PICCS, RD-MBIR, and SD-FBP (2.7 ± 0.4/2.8 ± 0.4/2.9 ± 0.6) compared with RD-FBP (1.5 ± 0.4) and RD-ASIR (1.8 ± 0.44). A similar trend was seen with 3D image quality scores. Polyp conspicuity scores were similar between SD-FBP/RD-PICCS/RD-MBIR (3.5 ± 0.6/3.2 ± 0.8/3.3 ± 0.6). CONCLUSION Sub-milliSievert CTC performed with iterative reconstruction techniques demonstrate decreased image quality compared to SD, but improved image quality compared to RD images reconstructed with FBP. KEY POINTS • CT colonography dose can be substantially lowered using advanced iterative reconstruction techniques. • Iterative reconstruction techniques (MBIR/PICCS) reduce image noise and improve image quality. • The PICCS/MBIR-reconstructed, reduced-dose series shows decreased 2D/3D image quality compared to the standard-dose series. • Polyp conspicuity was similar on standard-dose images compared to reduced-dose images reconstructed with MBIR/PICCS.
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Affiliation(s)
- Meghan G Lubner
- Departments of Radiology, University of Wisconsin School of Medicine and Public Health, E3/311 Clinical Sciences Center, 600 Highland Ave, Madison, WI, 53792-3252, USA,
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Näppi JJ, Regge D, Yoshida H. Context-specific method for detection of soft-tissue lesions in non-cathartic low-dose dual-energy CT colonography. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2015; 9414:94142Y. [PMID: 25964710 DOI: 10.1117/12.2081284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
In computed tomographic colonography (CTC), orally administered fecal-tagging agents can be used to indicate residual feces and fluid that could otherwise hide or imitate lesions on CTC images of the colon. Although the use of fecal tagging improves the detection accuracy of CTC, it can introduce image artifacts that may cause lesions that are covered by fecal tagging to have a different visual appearance than those not covered by fecal tagging. This can distort the values of image-based computational features, thereby reducing the accuracy of computer-aided detection (CADe). We developed a context-specific method that performs the detection of lesions separately on lumen regions covered by air and on those covered by fecal tagging, thereby facilitating the optimization of detection parameters separately for these regions and their detected lesion candidates to improve the detection accuracy of CADe. For pilot evaluation, the method was integrated into a dual-energy CADe (DE-CADe) scheme and evaluated by use of leave-one-patient-out evaluation on 66 clinical non-cathartic low-dose dual-energy CTC (DE-CTC) cases that were acquired at a low effective radiation dose and reconstructed by use of iterative image reconstruction. There were 22 colonoscopy-confirmed lesions ≥6 mm in size in 21 patients. The DE-CADe scheme detected 96% of the lesions at a median of 6 FP detections per patient. These preliminary results indicate that the use of context-specific detection can yield high detection accuracy of CADe in non-cathartic low-dose DE-CTC examinations.
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Affiliation(s)
- Janne J Näppi
- 3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 25 New Chardon Street, Suite 400C, Boston, MA 02114, USA
| | - Daniele Regge
- Institute for Cancer Research and Treatment, Strada Provinciale 142, IT-10060 Candiolo, Turin, Italy
| | - Hiroyuki Yoshida
- 3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 25 New Chardon Street, Suite 400C, Boston, MA 02114, USA
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Shen H, Liang D, Luo M, Duan C, Cai W, Zhu S, Qiu J, Li W. Pilot study on image quality and radiation dose of CT colonography with adaptive iterative dose reduction three-dimensional. PLoS One 2015; 10:e0117116. [PMID: 25635839 PMCID: PMC4311968 DOI: 10.1371/journal.pone.0117116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 12/17/2014] [Indexed: 12/19/2022] Open
Abstract
Objective To investigate image quality and radiation dose of CT colonography (CTC) with adaptive iterative dose reduction three-dimensional (AIDR3D). Methods Ten segments of porcine colon phantom were collected, and 30 pedunculate polyps with diameters ranging from 1 to 15 mm were simulated on each segment. Image data were acquired with tube voltage of 120 kVp, and current doses of 10 mAs, 20 mAs, 30 mAs, 40 mAs, 50 mAs, respectively. CTC images were reconstructed using filtered back projection (FBP) and AIDR3D. Two radiologists blindly evaluated image quality. Quantitative evaluation of image quality included image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Qualitative image quality was evaluated with a five-score scale. Radiation dose was calculated based on dose-length product. Ten volunteers were examined supine 50 mAs with FBP and prone 20 mAs with AIDR3D, and image qualities were assessed. Paired t test was performed for statistical analysis. Results For 20 mAs with AIDR3D and 50 mAs with FBP, image noise, SNRs and CNRs were (16.4 ± 1.6) HU vs. (16.8 ± 2.6) HU, 1.9 ± 0.2 vs. 1.9 ± 0.4, and 62.3 ± 6.8 vs. 62.0 ± 6.2, respectively; qualitative image quality scores were 4.1 and 4.3, respectively; their differences were all not statistically significant. Compared with 50 mAs with FBP, radiation dose (1.62 mSv) of 20 mAs with AIDR3D was decreased by 60.0%. There was no statistically significant difference in image noise, SNRs, CNRs and qualitative image quality scores between prone 20 mAs with AIDR3D and supine 50 mAs with FBP in 10 volunteers, the former reduced radiation dose by 61.1%. Conclusion Image quality of CTC using 20 mAs with AIDR3D could be comparable to standard 50 mAs with FBP, radiation dose of the former reduced by about 60.0% and was only 1.62 mSv.
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Affiliation(s)
- Hesong Shen
- Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Dan Liang
- Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Mingyue Luo
- Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- * E-mail:
| | - Chaijie Duan
- Research Center of Biomedical Engineering, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong, China
| | - Wenli Cai
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Shanshan Zhu
- Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jianping Qiu
- Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Wenru Li
- Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
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Lambert L, Ourednicek P, Jahoda J, Lambertova A, Danes J. Model-based vs hybrid iterative reconstruction technique in ultralow-dose submillisievert CT colonography. Br J Radiol 2015; 88:20140667. [PMID: 25605346 DOI: 10.1259/bjr.20140667] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE To compare image quality of different reconstruction techniques in submillisievert ultralow-dose CT colonography (CTC) and to correlate colonic findings with subsequent optical colonoscopy. METHODS 58 patients underwent ultralow-dose CTC. The images were reconstructed with filtered back projection (FBP), hybrid iterative reconstruction (HIR) or model-based iterative reconstruction (MBIR) techniques. In each segment, endoluminal noise (expressed as standard deviation of endoluminal density) was measured and image quality was rated on a five-point Likert scale by two independent readers. Colonic lesions were evaluated in consensus and correlated with subsequent optical colonoscopy where possible. RESULTS The estimated radiation dose was 0.41 ± 0.05 mSv for the supine and 0.42 ± 0.04 mSv for the prone acquisitions. In the endoluminal view, the image quality was rated better in HIR, whereas better scores were obtained in MBIR in the cross-sectional view, where the endoluminal noise was the lowest (p < 0.0001). Five (26%) polyps were not identified using both computer-aided detection and endoluminal inspection in FBP images vs only one (5%) in MBIR and none in HIR images. CONCLUSION This study showed that in submillisievert ultralow-dose CTC, the image quality for the endoluminal view is better when HIR is used, whereas MBIR yields superior images for the cross-sectional view. The inferior quality of images reconstructed with FBP may result in decreased detection of colonic lesions. ADVANCES IN KNOWLEDGE Radiation dose from CTC can be safely reduced <1 mSv for both positions when iterative reconstruction is used. MBIR provides better image quality in the cross-sectional view and HIR in the endoluminal view.
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Affiliation(s)
- L Lambert
- 1 Department of Radiology, First Faculty of Medicine of Charles University in Prague, Prague, Czech Republic
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Näppi JJ, Tachibana R, Regge D, Yoshida H. Information-Preserving Pseudo-Enhancement Correction for Non-Cathartic Low-Dose Dual-Energy CT Colonography. ABDOMINAL IMAGING : COMPUTATIONAL AND CLINICAL APPLICATIONS : 6TH INTERNATIONAL WORKSHOP, ABDI 2014, HELD IN CONJUNCTION WITH MICCAI 2014, CAMBRIDGE, MA, USA, SEPTEMBER 14, 2014. ABDI (WORKSHOP) (6TH : 2014 : CAMBRIDGE, MASS.) 2014; 8676:159-168. [PMID: 26236780 PMCID: PMC4521593 DOI: 10.1007/978-3-319-13692-9_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
In CT colonography (CTC), orally administered positive-contrast fecal-tagging agents can cause artificial elevation of the observed radiodensity of adjacent soft tissue. Such pseudo-enhancement makes it challenging to differentiate polyps and folds reliably from tagged materials, and it is also present in dual-energy CTC (DE-CTC). We developed a method that corrects for pseudo-enhancement on DE-CTC images without distorting the dual-energy information contained in the data. A pilot study was performed to evaluate the effect of the method visually and quantitatively by use of clinical non-cathartic low-dose DE-CTC data from 10 patients including 13 polyps covered partially or completely by iodine-based fecal tagging. The results indicate that the proposed method can be used to reduce the pseudo-enhancement distortion of DE-CTC images without losing material-specific dual-energy information. The method has potential application in improving the accuracy of automated image-processing applications, such as computer-aided detection and virtual bowel cleansing in CTC.
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Affiliation(s)
- Janne J. Näppi
- 3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 25 New Chardon Street, Suite 400C, Boston, MA 02114, USA
| | - Rie Tachibana
- 3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 25 New Chardon Street, Suite 400C, Boston, MA 02114, USA
| | - Daniele Regge
- Institute for Cancer Research and Treatment, Candiolo Str. Prov. 142, 10060 Turin, Italy
| | - Hiroyuki Yoshida
- 3D Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 25 New Chardon Street, Suite 400C, Boston, MA 02114, USA
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Evaluation of dose reduction and image quality in CT colonography: comparison of low-dose CT with iterative reconstruction and routine-dose CT with filtered back projection. Eur Radiol 2014; 25:221-9. [PMID: 25097128 DOI: 10.1007/s00330-014-3350-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/31/2014] [Accepted: 07/15/2014] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To prospectively evaluate the radiation dose and image quality comparing low-dose CT colonography (CTC) reconstructed using different levels of iterative reconstruction techniques with routine-dose CTC reconstructed with filtered back projection. METHODS Following institutional ethics clearance and informed consent procedures, 210 patients underwent screening CTC using automatic tube current modulation for dual positions. Examinations were performed in the supine position with a routine-dose protocol and in the prone position, randomly applying four different low-dose protocols. Supine images were reconstructed with filtered back projection and prone images with iterative reconstruction. Two blinded observers assessed the image quality of endoluminal images. Image noise was quantitatively assessed by region-of-interest measurements. RESULTS The mean effective dose in the supine series was 1.88 mSv using routine-dose CTC, compared to 0.92, 0.69, 0.57, and 0.46 mSv at four different low doses in the prone series (p < 0.01). Overall image quality and noise of low-dose CTC with iterative reconstruction were significantly improved compared to routine-dose CTC using filtered back projection. The lowest dose group had image quality comparable to routine-dose images. CONCLUSIONS Low-dose CTC with iterative reconstruction reduces the radiation dose by 48.5 to 75.1% without image quality degradation compared to routine-dose CTC with filtered back projection. KEY POINTS • Low-dose CTC reduces radiation dose ≥ 48.5% compared to routine-dose CTC. • Iterative reconstruction improves overall CTC image quality compared with FBP. • Iterative reconstruction reduces overall CTC image noise compared with FBP. • Automated exposure control with iterative reconstruction is useful for low-dose CTC.
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The time has arrived for national reimbursement of screening CT colonography. AJR Am J Roentgenol 2013; 201:73-9. [PMID: 23789660 DOI: 10.2214/ajr.13.10656] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE CT colonography (CTC) has been fully validated as an accurate screening test for colorectal carcinoma and is being disseminated globally. There is an abundance of new literature addressing the prior concerns of the U.S. Preventive Services Task Force and the Centers for Medicare & Medicaid Services. Specific areas related to radiation dose, extracolonic findings, and generalizability of CTC to senior patients are discussed. CONCLUSION The time has arrived for national reimbursement of CTC in the United States.
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