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Yap LPP, Sani FM, Chung E, Gowdh NFM, Ng WL, Wong JHD. Customised weight-based volume contrast media protocol for multiphase abdominal computed tomography. Singapore Med J 2024:00077293-990000000-00085. [PMID: 38305361 DOI: 10.4103/singaporemedj.smj-2021-461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 10/19/2022] [Indexed: 02/03/2024]
Abstract
INTRODUCTION Multiphase computed tomography (CT) using fixed volume contrast media may lead to high radiation exposure and toxicity in patients with low body weight. We evaluated a customised weight-based protocol for multiphase CT in terms of radiation exposure, image quality and cost savings. METHODS A total of 224 patients were recruited. An optimised CT protocol was applied using 100 kV and 1 mL/kg of contrast media dosing. The image quality and radiation dose exposure of this CT protocol were compared to those of a standard 120 kV, 80 mL fixed volume protocol. The radiation dose information and CT Hounsfield units were recorded. The signal-to-noise ratio, contrast-to-noise ratio (CNR) and figure of merit (FOM) were used as comparison metrics. The images were assessed for contrast opacification and visual quality by two radiologists. The renal function, contrast media volume and cost were also evaluated. RESULTS The median effective dose was lowered by 16% in the optimised protocol, while the arterial phase images achieved significantly higher CNR and FOM. The radiologists' evaluation showed more than 97% absolute agreement with no significant differences in image quality. No significant differences were found in the pre- and post-CT estimated glomerular filtration rate. However, contrast media usage was significantly reduced by 1,680 mL, with an overall cost savings of USD 421 in the optimised protocol. CONCLUSION The optimised weight-based protocol is cost-efficient and lowers radiation dose while maintaining overall contrast enhancement and image quality.
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Affiliation(s)
- Lilian Poh Poh Yap
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Biomedical Imaging, Universiti Malaya Medical Centre, Lembah Pantai, Kuala Lumpur, Malaysia
| | - Fadhli Mohamed Sani
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Biomedical Imaging, Universiti Malaya Medical Centre, Lembah Pantai, Kuala Lumpur, Malaysia
| | - Eric Chung
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Biomedical Imaging, Universiti Malaya Medical Centre, Lembah Pantai, Kuala Lumpur, Malaysia
| | - Nadia Fareeda Muhammad Gowdh
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Biomedical Imaging, Universiti Malaya Medical Centre, Lembah Pantai, Kuala Lumpur, Malaysia
| | - Wei Lin Ng
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Biomedical Imaging, Universiti Malaya Medical Centre, Lembah Pantai, Kuala Lumpur, Malaysia
| | - Jeannie Hsiu Ding Wong
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Biomedical Imaging, Universiti Malaya Medical Centre, Lembah Pantai, Kuala Lumpur, Malaysia
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Macri F, Khasanova E, Niu BT, Parakh A, Patino M, Kambadakone A, Sahani DV. Optimal Abdominal CT Image Quality in Non-Lean Patients: Customization of CM Injection Protocols and Low-Energy Acquisitions. Diagnostics (Basel) 2023; 13:2279. [PMID: 37443673 PMCID: PMC10377374 DOI: 10.3390/diagnostics13132279] [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: 02/24/2023] [Revised: 06/20/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
We compared the image quality of abdominopelvic single-energy CT with 100 kVp (SECT-100 kVp) and dual-energy CT with 65 keV (DECT-65 keV) obtained with customized injection protocols to standard abdominopelvic CT scans (SECT-120 kVp) with fixed volumes of contrast media (CM). We retrospectively included 91 patients (mean age, 60.7 ± 15.8 years) with SECT-100 kVp and 83 (mean age, 60.3 ± 11.7 years) patients with DECT-65 keV in portovenous phase. Total body weight-based customized injection protocols were generated by a software using the following formula: patient weight (kg) × 0.40/contrast concentration (mgI/mL) × 1000. Patients had a prior abdominopelvic SECT-120 kVp with fixed injection. Iopamidol-370 was administered for all examinations. Quantitative and qualitative image quality comparisons were made between customized and fixed injection protocols. Compared to SECT-120 kVp, customized injection yielded a significant reduction in CM volume (mean difference = 9-12 mL; p ≤ 0.001) and injection rate (mean differences = 0.2-0.4 mL/s; p ≤ 0.001) in all weight categories. Improvements in attenuation, noise, signal-to-noise and contrast-to-noise ratios were observed for both SECT-100 kVp and DECT-65 keV compared to SECT-120 kVp in all weight categories (e.g., pancreas DECT-65 keV, 1.2-attenuation-fold increase vs. SECT-120 kVp; p < 0.001). Qualitative scores were ≥4 in 172 cases (98.8.4%) with customized injections and in all cases with fixed injections (100%). These findings suggest that customized CM injection protocols may substantially reduce iodine dose while yielding higher image quality in SECT-100 kVp and DECT-65 keV abdominopelvic scans compared to SECT-120 kVp using fixed CM volumes.
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Affiliation(s)
- Francesco Macri
- Department of Radiology, Geneva University Hospitals, University of Geneva, 1211 Geneva, Switzerland
| | - Elina Khasanova
- Department of Radiology, Geneva University Hospitals, University of Geneva, 1211 Geneva, Switzerland
| | - Bonnie T Niu
- Faculty of Medicine, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Anushri Parakh
- Department of Radiology, Abdominal Division, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Manuel Patino
- Department of Radiology, Abdominal Division, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Avinash Kambadakone
- Department of Radiology, Abdominal Division, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Dushyant V Sahani
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
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Kesen S, Svensson A, Thor D, Brismar TB. Hepatic enhancement at computed tomography: is there a dependence on body weight past institutional contrast dosing limits? Acta Radiol 2023; 64:435-440. [PMID: 35266404 PMCID: PMC9905147 DOI: 10.1177/02841851221079014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Although described in product monographs, the maximum contrast media (CM) dose at computed tomography (CT) varies among institutions. PURPOSE To investigate whether an upper limit of 40 g of iodine in women and 50 g in men is sufficient or if there is a body weight (BW) dependence of mean hepatic enhancement (MHE) beyond those thresholds. MATERIAL AND METHODS At our institution, CM injection duration is fixed to 30 s and dosed 600 mg iodine/kg up to 40 g in women and 50 g in men. Pre- and post-contrast hepatic attenuation values (HU) were retrospectively obtained in 200 women and 200 men with glomerular filtration rate >45 mL/min undergoing 18-flurodeoxyglucose PET-CT (18F-FDG PET-CT) of which half weighed below and half above those dose thresholds using iodixanol 320 mg iodine/mL or iomeprol 400 mg iodine/mL. The correlation between BW and MHE was assessed by simple linear regression. RESULTS Weight range was 41-120 kg in women and 47-137 kg in men. There was no significant relationship between MHE and BW in women receiving <40 g (r = -0.05, P = 0.63) or in men receiving <50 g (r = 0.18, P = 0.07). Above those thresholds there was an inverse relationship (r = -0.64, P<0.001 in women and r = -0.30, P<0.002 in men). There was no apparent upper limit where the dependence of hepatic MHE on BW decreased. Hepatosteatosis limited MHE. CONCLUSION Adjusting CM to BW diminishes the dependence of MHE on BW. There was no apparent upper limit for the relationship between BW and MHE in heavier patients at CM-enhanced CT.
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Affiliation(s)
- Savas Kesen
- Division of Radiology, Department of Clinical Science, Intervention and Technology at Karolinska Institutet, Stockholm, Sweden,Department of Radiology, Södersjukhuset, Stockholm, Sweden,Savas Kesen, Division of Radiology, Department of Clinical Science, Intervention and Technology at Karolinska Institutet, Stockholm, Sweden and Södersjukhuset, Department of Radiology, Stockholm, Sweden.
| | - Anders Svensson
- Division of Radiology, Department of Clinical Science, Intervention and Technology at Karolinska Institutet, Stockholm, Sweden,Department of Radiology, Imaging and Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Daniel Thor
- Medical Radiation Physics and Nuclear Medicine, Imaging and Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Torkel B. Brismar
- Division of Radiology, Department of Clinical Science, Intervention and Technology at Karolinska Institutet, Stockholm, Sweden,Department of Radiology, Imaging and Physiology, Karolinska University Hospital, Stockholm, Sweden
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Setiawan H, Chen C, Abadi E, Fu W, Marin D, Ria F, Samei E. A patient-informed approach to predict iodinated-contrast media enhancement in the liver. Eur J Radiol 2022; 156:110555. [PMID: 36265222 PMCID: PMC10777297 DOI: 10.1016/j.ejrad.2022.110555] [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: 03/06/2022] [Revised: 07/20/2022] [Accepted: 10/07/2022] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To devise a patient-informed time series model that predicts liver contrast enhancement, by integrating clinical data and pharmacokinetics models, and to assess its feasibility to improve enhancement consistency in contrast-enhanced liver CT scans. METHODS The study included 1577 Chest/Abdomen/Pelvis CT scans, with 70-30% training/validation-testing split. A Gaussian function was used to approximate the early arterial, late arterial, and the portal venous phases of the contrast perfusion curve of each patient using their respective bolus tracking and diagnostic scan data. Machine learning models were built to predict the Gaussian parameters of each patient using the patient attributes (weight, height, age, sex, BMI). Pearson's coefficient, mean absolute error, and root mean squared error were used to assess the prediction accuracy. RESULTS The integration of the pharmacokinetics model with a two-layered neural network achieved the highest prediction accuracy on the test data (R2 = 0.61), significantly exceeding the performance of the pharmacokinetics model alone (R2 = 0.11). Applying the model demonstrated that adjusting the contrast administration directed by the model may reduce clinical enhancement inconsistency by up to 40 %. CONCLUSIONS A new model using a Gaussian function and supervised machine learning can be used to build liver parenchyma contrast enhancement prediction model. The model can have utility in clinical settings to optimize and improve consistency in contrast-enhanced liver imaging.
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Affiliation(s)
- Hananiel Setiawan
- Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Center for Virtual Imaging Trials, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Graduate Program in Medical Physics, School of Medicine, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA.
| | - Chaofan Chen
- School of Computing and Information Science, The University of Maine, 5711 Boardman Hall, Room 348, Orono, ME 04469, USA
| | - Ehsan Abadi
- Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Center for Virtual Imaging Trials, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Graduate Program in Medical Physics, School of Medicine, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, 305 Nello L. Teer Engineering Building, Box 90271, Durham, NC 27708, USA; Department of Radiology, School of Medicine, Duke University, Box 3808 DUMC, Durham, NC 27710, USA
| | - Wanyi Fu
- Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Center for Virtual Imaging Trials, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, 305 Nello L. Teer Engineering Building, Box 90271, Durham, NC 27708, USA
| | - Daniele Marin
- Graduate Program in Medical Physics, School of Medicine, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Department of Radiology, School of Medicine, Duke University, Box 3808 DUMC, Durham, NC 27710, USA
| | - Francesco Ria
- Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Center for Virtual Imaging Trials, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Clinical Imaging Physics Group, Duke University Health System, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA
| | - Ehsan Samei
- Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Center for Virtual Imaging Trials, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Clinical Imaging Physics Group, Duke University Health System, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Graduate Program in Medical Physics, School of Medicine, Duke University, 2424 Erwin Rd, Ste. 302, Durham, NC 27705, USA; Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, 305 Nello L. Teer Engineering Building, Box 90271, Durham, NC 27708, USA; Department of Biomedical Engineering, Pratt School of Engineering, Duke University, 305 Nello L. Teer Engineering Building, Box 90271, Durham, NC 27708, USA; Department of Radiology, School of Medicine, Duke University, Box 3808 DUMC, Durham, NC 27710, USA; Physics Building, Science Drive Campus, Box 90305, Durham, NC 27708, USA
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He M, Wang X, Xu J, Li J, Chang X, Zins M, Jin Z, Xue H. Diffuse Involvement of Pancreas is not Always Autoimmune Pancreatitis. Acad Radiol 2022; 29:1523-1531. [PMID: 35279380 DOI: 10.1016/j.acra.2022.01.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/09/2022] [Accepted: 01/16/2022] [Indexed: 02/07/2023]
Abstract
RATIONALE AND OBJECTIVES To determine the prevalence of diffuse involvement of pancreas and to identify the findings of malignancies using enhancement computed tomography (CT). MATERIALS AND METHODS A total of 1,0249 patients performed enhancement CT in our hospital over 62 months were investigated and the final study cohort includes 245 patients (170 males, 75 females; mean age, 56.94 ± 12.17 years). The reference standard is the final clinical/pathological diagnosis. The lesion-to-aorta enhancement ratio (LAR) on the pancreatic arterial phase, portal phase and delayed phase (DP) and the traditional CT findings were evaluated. Intergroup comparisons between malignancies and non-malignancies lesions were performed. Univariate and multivariate analyses were conducted to identify findings predicting malignancies. RESULTS The prevalence of malignancy was 45.3% (111/245) of diffuse enlargement of pancreas. All benign lesions were autoimmune pancreatitis 54.7% (n = 134). The most common malignant lesion was pancreatic ductal adenocarcinoma (n = 88, 35.9%). Other rare lesions with malignant potential included pancreatic neuroendocrine tumor (n = 11, 4.5%), lymphoma (n = 4, 1.6%), metastasis (n = 4, 1.6%), solid pseudopapillary neoplasm (n = 3, 1.2%) and acinar cell carcinoma (n = 1, 0.4%). Residual normal pancreas parenchyma, heterogeneity, short axis (cut-off value, 3.15 cm) and LARDP (cut-off value, 0.75) were independent predictors of malignancies. When the above predictors were combined, a sensitivity of 94.2%, a specificity of 90.8% were attained. CONCLUSION Diffuse involvement of the pancreas is rare and is not a specific sign of autoimmune pancreatitis, and it is associated with a wide spectrum of malignant conditions. Dynamic enhancement CT is helpful to identifying malignancies.
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Affiliation(s)
- Ming He
- Department of Radiology, Guangdong Provincial People's Hospital & Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, People's Republic of China; Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shuaifuyuan No.1, Dongcheng District, Beijing 100703, China
| | - Xiheng Wang
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shuaifuyuan No.1, Dongcheng District, Beijing 100703, China
| | - Jin Xu
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shuaifuyuan No.1, Dongcheng District, Beijing 100703, China
| | - Juan Li
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shuaifuyuan No.1, Dongcheng District, Beijing 100703, China
| | - Xiaoyan Chang
- Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Marc Zins
- Department of Rathology, Groupe Hospitalier Paris Saint Joseph, Paris, France
| | - Zhengyu Jin
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shuaifuyuan No.1, Dongcheng District, Beijing 100703, China
| | - Huadan Xue
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shuaifuyuan No.1, Dongcheng District, Beijing 100703, China.
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Beyer G, Hoffmeister A, Michl P, Gress TM, Huber W, Algül H, Neesse A, Meining A, Seufferlein TW, Rosendahl J, Kahl S, Keller J, Werner J, Friess H, Bufler P, Löhr MJ, Schneider A, Lynen Jansen P, Esposito I, Grenacher L, Mössner J, Lerch MM, Mayerle J. S3-Leitlinie Pankreatitis – Leitlinie der Deutschen Gesellschaft für Gastroenterologie, Verdauungs- und Stoffwechselkrankheiten (DGVS) – September 2021 – AWMF Registernummer 021-003. ZEITSCHRIFT FUR GASTROENTEROLOGIE 2022; 60:419-521. [PMID: 35263785 DOI: 10.1055/a-1735-3864] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Georg Beyer
- Medizinische Klinik und Poliklinik II, LMU Klinikum, Ludwig-Maximilians-Universität München, Deutschland
| | - Albrecht Hoffmeister
- Bereich Gastroenterologie, Klinik und Poliklinik für Onkologie, Gastroenterologie, Hepatologie Pneumologie und Infektiologie, Universitätsklinikum Leipzig, Deutschland
| | - Patrick Michl
- Universitätsklinik u. Poliklinik Innere Medizin I mit Schwerpunkt Gastroenterologie, Universitätsklinikum Halle, Deutschland
| | - Thomas Mathias Gress
- Klinik für Gastroenterologie und Endokrinologie, Universitätsklinikum Gießen und Marburg, Deutschland
| | - Wolfgang Huber
- Comprehensive Cancer Center München TUM, II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, München, Deutschland
| | - Hana Algül
- Comprehensive Cancer Center München TUM, II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, München, Deutschland
| | - Albrecht Neesse
- Klinik für Gastroenterologie, gastrointestinale Onkologie und Endokrinologie, Universitätsmedizin Göttingen, Deutschland
| | - Alexander Meining
- Medizinische Klinik und Poliklinik II Gastroenterologie und Hepatologie, Universitätsklinikum Würzburg, Deutschland
| | | | - Jonas Rosendahl
- Universitätsklinik u. Poliklinik Innere Medizin I mit Schwerpunkt Gastroenterologie, Universitätsklinikum Halle, Deutschland
| | - Stefan Kahl
- Klinik für Innere Medizin m. Schwerpkt. Gastro./Hämat./Onko./Nephro., DRK Kliniken Berlin Köpenick, Deutschland
| | - Jutta Keller
- Medizinische Klinik, Israelitisches Krankenhaus, Hamburg, Deutschland
| | - Jens Werner
- Klinik für Allgemeine, Viszeral-, Transplantations-, Gefäß- und Thoraxchirurgie, Universitätsklinikum München, Deutschland
| | - Helmut Friess
- Klinik und Poliklinik für Chirurgie, Klinikum rechts der Isar, München, Deutschland
| | - Philip Bufler
- Klinik für Pädiatrie m. S. Gastroenterologie, Nephrologie und Stoffwechselmedizin, Charité Campus Virchow-Klinikum - Universitätsmedizin Berlin, Deutschland
| | - Matthias J Löhr
- Department of Gastroenterology, Karolinska, Universitetssjukhuset, Stockholm, Schweden
| | - Alexander Schneider
- Klinik für Gastroenterologie und Hepatologie, Klinikum Bad Hersfeld, Deutschland
| | - Petra Lynen Jansen
- Deutsche Gesellschaft für Gastroenterologie, Verdauungs- und Stoffwechselkrankheiten (DGVS), Berlin, Deutschland
| | - Irene Esposito
- Pathologisches Institut, Heinrich-Heine-Universität und Universitätsklinikum Duesseldorf, Duesseldorf, Deutschland
| | - Lars Grenacher
- Conradia Radiologie München Schwabing, München, Deutschland
| | - Joachim Mössner
- Bereich Gastroenterologie, Klinik und Poliklinik für Onkologie, Gastroenterologie, Hepatologie Pneumologie und Infektiologie, Universitätsklinikum Leipzig, Deutschland
| | - Markus M Lerch
- Klinik für Innere Medizin A, Universitätsmedizin Greifswald, Deutschland.,Klinikum der Ludwig-Maximilians-Universität (LMU) München, Deutschland
| | - Julia Mayerle
- Medizinische Klinik und Poliklinik II, LMU Klinikum, Ludwig-Maximilians-Universität München, Deutschland
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A Metric for Quantification of Iodine Contrast Enhancement (Q-ICE) in Computed Tomography. J Comput Assist Tomogr 2021; 45:870-876. [PMID: 34469906 DOI: 10.1097/rct.0000000000001215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Poor contrast enhancement is related to issues with examination execution, contrast prescription, computed tomography (CT) protocols, and patient conditions. Currently, our community has no metric to monitor true enhancement on routine single-phase examinations because this requires knowledge of both pre- and postcontrast CT number. PURPOSE We propose an automatable solution to quantifying contrast enhancement without requiring a dedicated noncontrast series. METHODS The difference in CT number between a target region in an enhanced and unenhanced image defines the metric "quantification of iodine contrast enhancement" (Q-ICE). Quantification of iodine contrast enhancement uses the noncontrast bolus tracking baseline image from routine abdominal examinations, which mitigates the need for a dedicated noncontrast series. We applied this method retrospectively to 312 patient livers from 2 sites between 2017 and 2020. Each site used a weight-based contrast injection protocol for weights 60 to 113 kg and a constant volume less than 60 kg and greater than 113 kg. Hypothesis testing was performed to compare Q-ICE between sites and detect Q-ICE dependence on weight and kilovoltage (kV). RESULTS Mean Q-ICE differed between sites (P = 0.004) by 4.96 Hounsfield unit with 95% confidence interval (1.63-8.28), albeit this difference was roughly 2 times smaller than the SD in Q-ICE across patients at a single site. For patients between 60 and 113 kg, we did not observe evidence of Q-ICE varying with patient weight (P = 0.920 and 0.064 for 120 and 140 kV, respectively). The Q-ICE did vary with patient weight for patients less than 60 kg (P = 0.003) and greater than 113 kg (P = 0.04). We observed a roughly 10 Hounsfield unit reduction in Q-ICE liver for patients scanned with 140 versus 120 kV. We observed several underenhancing examinations with an arterial phase appearance motivating our CT protocol optimization team to consider increasing the delay for slowly enhancing patients. CONCLUSIONS A quality metric for quantifying CT contrast enhancement was developed and suggested tangible opportunities for quality improvement and potential financial savings.
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Costa AF, Peet K. Contrast media injection protocol for portovenous phase abdominal CT: does a fixed injection duration improve hepatic enhancement over a fixed injection rate? Abdom Radiol (NY) 2021; 46:2968-2975. [PMID: 33386915 DOI: 10.1007/s00261-020-02919-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 12/10/2020] [Accepted: 12/12/2020] [Indexed: 11/28/2022]
Abstract
PURPOSE To assess whether a fixed contrast media (CM) injection duration improves the magnitude and inter-patient variability in hepatic enhancement over a fixed injection rate. METHODS Outpatients who underwent portovenous phase abdominal CT (fixed duration, February-November 2018; fixed rate, January-July 2020) with 1.22 mL/kg iohexol 350 were included. Subjects with liver, kidney or heart disease were excluded. The number of subjects and injection protocols were as follows: fixed duration arm, 56 women, 60 men, 35 s injection duration; fixed rate arm, 66 women, 62 men, 3 mL/s injection rate. Liver attenuation measurements were obtained from regions of interest on pre- and post-contrast images. Mean hepatic enhancement (MHE) and MHE normalized to iodine dose (MHE/I) were compared (unpaired t-tests and F-tests). RESULTS There was no statistically significant difference in age, weight, body mass index or CM dosing (p > 0.05). Enhancement indices were significantly lower in the fixed rate group as compared to the fixed duration group, as follows: MHE, 50.0 ± 12 vs. 54.8 ± 11 HU (p = 0.001); and MHE/I, 1.53 ± 0.43 vs. 1.66 ± 0.51 HU/g, (p = 0.04). However, there was no significant difference in the variances of MHE (p = 0.51) and MHE/I (p = 0.08). CONCLUSION A fixed CM injection duration yields a greater magnitude in hepatic enhancement indices than a fixed injection rate. Inter-patient variability in hepatic enhancement indices do not significantly differ between the two injection protocols.
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Affiliation(s)
- Andreu F Costa
- Department of Diagnostic Radiology, Queen Elizabeth II Health Sciences Centre and Dalhousie University, Victoria General Building, 3rd floor, 1276 South Park Street, Halifax, NS, B3H 2Y9, Canada.
| | - Kris Peet
- Department of Diagnostic Radiology, Queen Elizabeth II Health Sciences Centre and Dalhousie University, Victoria General Building, 3rd floor, 1276 South Park Street, Halifax, NS, B3H 2Y9, Canada
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Yap LPP, Wong JHD, Muhammad Gowdh NF, Ng WL, Chung E, Eturajulu RC, Foo SAMK, Vijayananthan A, Sani FM. Customised weight-based volume contrast media protocol in CT of chest, abdomen and pelvis examination. J Med Imaging Radiat Sci 2021; 52:257-264. [PMID: 33531272 DOI: 10.1016/j.jmir.2021.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/18/2020] [Accepted: 01/14/2021] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Fixed volume (FV) contrast media administration during CT examination is the standard practice in most healthcare institutions. We aim to validate a customised weight-based volume (WBV) method and compare it to the conventional FV methods, introduced in a regional setting. METHODS 220 patients underwent CT of the chest, abdomen and pelvis (CAP) using a standard FV protocol, and subsequently, a customised 1.0 mL/kg WBV protocol within one year. Both image sets were assessed for contrast enhancement using CT attenuation at selected regions-of-interest (ROIs). The visual image quality was evaluated by three radiologists using a 4-point Likert scale. Quantitative CT attenuation was correlated with the visual quality assessment to determine the HU's enhancement indicative of the image quality grades. Contrast media usage was calculated to estimate cost-savings from both protocols. RESULTS Mean patient age was 61 ± 14 years, and weight was 56.1 ± 8.7 kg. FV protocol produced higher contrast enhancement than WBV, p < 0.001. CT images' overall contrast enhancement was negatively correlated with body weight for FV protocol while the WBV protocol produced more consistent enhancement across different body weight. More than 90% of the images from both protocols were graded "Excellent". WBV protocol also enabled a 28% cost reduction with cost savings of US$1238. CONCLUSION The customised WBV protocol produced CT images which were comparable to FV protocol for CT CAP examinations. A median CT value of 100 HU can be an indicator of good image quality for the WBV protocol.
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Affiliation(s)
- Lilian Poh Poh Yap
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia; Research Unit of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
| | - Jeannie Hsiu Ding Wong
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Nadia Fareeda Muhammad Gowdh
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
| | - Wei Lin Ng
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
| | - Eric Chung
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
| | - Ravi Chanthriga Eturajulu
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia; Research Unit of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
| | - Sue Anne Manushya Kaur Foo
- Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia; Research Unit of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
| | - Anushya Vijayananthan
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
| | - Fadhli Mohamed Sani
- Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Lembah Pantai, 59100 Kuala Lumpur, Malaysia
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Agostini A, Borgheresi A, Bruno F, Natella R, Floridi C, Carotti M, Giovagnoni A. New advances in CT imaging of pancreas diseases: a narrative review. Gland Surg 2021; 9:2283-2294. [PMID: 33447580 DOI: 10.21037/gs-20-551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Computed tomography (CT) plays a pivotal role as a diagnostic tool in many diagnostic and diffuse pancreatic diseases. One of the major limits of CT is related to the radiation exposure of young patients undergoing repeated examinations. Besides the standard CT protocol, the most recent technological advances, such as low-voltage acquisitions with high performance X-ray tubes and iterative reconstructions, allow for significant optimization of the protocol with dose reduction. The variety of CT tools are further expanded by the introduction of dual energy: the production of energy-selective images (i.e., virtual monochromatic images) improves the image contrast and lesion detection while the material-selective images (e.g., iodine maps or virtual unenhanced images) are valuable for lesion detection and dose reduction. The perfusion techniques provide diagnostic and prognostic information lesion and parenchymal vascularization and interstitium. Both dual energy and perfusion CT have the potential for pushing the limits of conventional CT from morphological evaluation to quantitative imaging applied to inflammatory and oncological diseases. Advances in post-processing of CT images, such as pancreatic volumetry, texture analysis and radiomics provide relevant information for pancreatic function but also for the diagnosis, management and prognosis of pancreatic neoplasms. Artificial intelligence is promising for optimization of the workflow in qualitative and quantitative analyses. Finally, basic concepts on the role of imaging on screening of pancreatic diseases will be provided.
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Affiliation(s)
- Andrea Agostini
- Department of Clinical, Special and Dental Sciences, University Politecnica delle Marche, Ancona (AN), Italy.,Department of Radiology, University Hospital "Umberto I - Lancisi - Salesi", Ancona (AN), Italy
| | - Alessandra Borgheresi
- Department of Radiology, University Hospital "Umberto I - Lancisi - Salesi", Ancona (AN), Italy
| | - Federico Bruno
- Department of Biotechnological and Applied Sciences, University of L'Aquila, L'Aquila, Italy
| | - Raffaele Natella
- Department of Precision Medicine, University of Campania "L. Vanvitelli", Naples, Italy
| | - Chiara Floridi
- Department of Clinical, Special and Dental Sciences, University Politecnica delle Marche, Ancona (AN), Italy.,Department of Radiology, University Hospital "Umberto I - Lancisi - Salesi", Ancona (AN), Italy
| | - Marina Carotti
- Department of Clinical, Special and Dental Sciences, University Politecnica delle Marche, Ancona (AN), Italy.,Department of Radiology, University Hospital "Umberto I - Lancisi - Salesi", Ancona (AN), Italy
| | - Andrea Giovagnoni
- Department of Clinical, Special and Dental Sciences, University Politecnica delle Marche, Ancona (AN), Italy.,Department of Radiology, University Hospital "Umberto I - Lancisi - Salesi", Ancona (AN), Italy
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11
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Zanardo M, Doniselli FM, Esseridou A, Agrò M, Panarisi NAR, Monti CB, Di Leo G, Sardanelli F. Lean body weight versus total body weight to calculate the iodinated contrast media volume in abdominal CT: a randomised controlled trial. Insights Imaging 2020; 11:132. [PMID: 33296036 PMCID: PMC7726088 DOI: 10.1186/s13244-020-00920-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/07/2020] [Indexed: 12/25/2022] Open
Abstract
Objectives Iodinated contrast media (ICM) could be more appropriately dosed on patient lean body weight (LBW) than on total body weight (TBW). Methods After Ethics Committee approval, trial registration NCT03384979, patients aged ≥ 18 years scheduled for multiphasic abdominal CT were randomised for ICM dose to LBW group (0.63 gI/kg of LBW) or TBW group (0.44 gI/kg of TBW). Abdominal 64-row CT was performed using 120 kVp, 100–200 mAs, rotation time 0.5 s, pitch 1, Iopamidol (370 mgI/mL), and flow rate 3 mL/s. Levene, Mann–Whitney U, and χ2 tests were used. The primary endpoint was liver contrast enhancement (LCE). Results Of 335 enrolled patients, 17 were screening failures; 44 dropped out after randomisation; 274 patients were analysed (133 LBW group, 141 TBW group). The median age of LBW group (66 years) was slightly lower than that of TBW group (70 years). Although the median ICM-injected volume was comparable between groups, its variability was larger in the former (interquartile range 27 mL versus 21 mL, p = 0.01). The same was for unenhanced liver density (IQR 10 versus 7 HU) (p = 0.02). Median LCE was 40 (35–46) HU in the LBW group and 40 (35–44) HU in the TBW group, without significant difference for median (p = 0.41) and variability (p = 0.23). Suboptimal LCE (< 40 HU) was found in 64/133 (48%) patients in the LBW group and 69/141 (49%) in the TBW group, but no examination needed repeating. Conclusions The calculation of the ICM volume to be administered for abdominal CT based on the LBW does not imply a more consistent LCE.
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Affiliation(s)
- Moreno Zanardo
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133, Milan, Italy.
| | - Fabio Martino Doniselli
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133, Milan, Italy.,Neuroradiology Department, Foundation IRCCS Neurological Institute "C. Besta", Via Celoria 11, 20133, Milan, Italy
| | - Anastassia Esseridou
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
| | - Massimiliano Agrò
- Postgraduate School in Radiodiagnostics, Università degli Studi di Milano, Via Festa del Perdono 7, 20122, Milan, Italy
| | - Nicol Antonina Rita Panarisi
- Postgraduate School in Radiodiagnostics, Università degli Studi di Milano, Via Festa del Perdono 7, 20122, Milan, Italy
| | - Caterina Beatrice Monti
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133, Milan, Italy
| | - Giovanni Di Leo
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
| | - Francesco Sardanelli
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133, Milan, Italy.,Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
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12
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Modeling Patient-Informed Liver Contrast Perfusion in Contrast-enhanced Computed Tomography. J Comput Assist Tomogr 2020; 44:882-886. [PMID: 33196597 DOI: 10.1097/rct.0000000000001095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To determine the correlation between patient attributes and contrast enhancement in liver parenchyma and demonstrate the potential for patient-informed prediction and optimization of contrast enhancement in liver imaging. METHODS The study included 418 chest/abdomen/pelvis computed tomography scans, with 75% to 25% training-testing split. Two regression models were built to predict liver parenchyma contrast enhancement over time: first model (model A) utilized patient attributes (height, weight, sex, age, bolus volume, injection rate, scan times, body mass index, lean body mass) and bolus-tracking data. A second model (model B) only used the patient attributes. Pearson coefficient was used to assess predictive accuracy. RESULTS Weight- and height-related features were found to be statistically significant predictors (P < 0.05), weight being the strongest. Of the 2 models, model A (r = 0.75) showed greater accuracy than model B (r = 0.42). CONCLUSIONS Patient attributes can be used to build prediction model for liver parenchyma contrast enhancement. The model can have utility in optimization and improved consistency in contrast-enhanced liver imaging.
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13
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Contrast Material Injection Protocol With the Dose Determined According to Lean Body Weight at Hepatic Dynamic Computed Tomography: Comparison Among Patients With Different Body Mass Indices. J Comput Assist Tomogr 2019; 43:736-740. [PMID: 31609293 DOI: 10.1097/rct.0000000000000909] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The objective of this study was to compare enhancement of the aorta and liver on hepatic dynamic computed tomography scans acquired with contrast material doses based on the lean body weight (LBW) or the total body weight (TBW). METHODS We randomly divided 529 patients (279 men, 250 women; median age, 66 years) scheduled for hepatic dynamic computed tomography into 2 groups. The LBW patients (n = 278) were injected with 679 mg iodine/kg (men) or 762 mg iodine/kg (women). The TBW group (n = 251) was injected with 600 mg iodine/kg TBW. Each group was subdivided into the 3 classes based on the body mass index (BMI; low, normal, high). Aortic enhancement during the hepatic arterial phase and hepatic enhancement during the portal venous phase was compared. The aortic and hepatic equivalence margins were 100 and 20 Hounsfield units, respectively. RESULTS Comparison of the median iodine dose in patients with a normal or high BMI showed that it was significantly lower under the LBW protocol than the TBW protocol (558.2 and 507.0 mg iodine/kg, P < 0.001, respectively). However, in patients with a low BMI, the LBW protocol delivered a significantly higher dose than the TBW protocol (620.7 vs 600.0 mg iodine/kg, P < 0.001). The 95% confidence interval for the difference in aortic and hepatic enhancement between the 2 protocols was within the range of the predetermined equivalence margins in all BMI subgroups. CONCLUSIONS Contrast enhancement was equivalent under both protocols. The LBW protocol can avoid iodine overdosing, especially in patients with a high BMI.
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14
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Nagayama Y, Tanoue S, Inoue T, Oda S, Nakaura T, Utsunomiya D, Yamashita Y. Dual-layer spectral CT improves image quality of multiphasic pancreas CT in patients with pancreatic ductal adenocarcinoma. Eur Radiol 2019; 30:394-403. [DOI: 10.1007/s00330-019-06337-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/30/2019] [Accepted: 06/21/2019] [Indexed: 12/19/2022]
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Svensson A, Thor D, Fischer MA, Brismar T. Dual source abdominal computed tomography: the effect of reduced X-ray tube voltage and intravenous contrast media dosage in patients with reduced renal function. Acta Radiol 2019; 60:293-300. [PMID: 29933715 DOI: 10.1177/0284185118783213] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND X-ray tube voltage (kVp) reduction increases intravenous contrast medium (CM) attenuation at computed tomography (CT), but tube output limits its use in large patients. PURPOSE To evaluate the feasibility and image quality of reducing CM dose by low kVp and using dual X-ray source at liver CT. MATERIAL AND METHODS Patients with estimated glomerular filtration rate (eGFR) < 45 mL/min (n = 43) aged 60-91 years (75 ± 7.7), weighing 42-114 kg (75 ± 15) were prospectively scanned using a reduced CM dose of 0.25 or 0.3 g iodine (I)/kg with 70 or 80 kVp respectively, using either single-source or dual-source CT depending on patient size. Liver contrast-to-noise ratio (CNR), liver noise, and muscle noise were quantitatively compared with those of 43 consecutive patients aged > 65 years with eGFR > 45 mL/min scanned using a standard abdominal protocol at 120 kVp after receiving 0.5 gI/kg. RESULTS There was no statistically significant difference in CNR, liver noise, or muscle noise at reduced CM protocols compared to the standard protocol: CNR was 4.6 (95% CI = 4.2-5.0) vs. 5.0 (95% CI = 4.5-5.5), liver noise was 11.1 (95% CI = 10.7-11.6) vs. 11.0 (95% CI = 10.5-11.6), muscle noise was 11.7 (95% CI = 11.2-12.1) vs. 10.8 (95% CI = 10.1-11.4). The mean SSDE was 70% higher with the reduced CM protocol. CONCLUSION CM dosage can be reduced by 40-50% with maintained measured noise and CNR in patients with BMIs of 15-36 kg/m2 by lowering the tube voltage and dual-source CT scanning of the liver.
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Affiliation(s)
- Anders Svensson
- Department of Clinical Science, Intervention and Technology at Karolinska Institutet, Division of Medical Imaging and Technology, Stockholm, Sweden
- Department of Radiology, Karolinska University Hospital in Huddinge, Stockholm, Sweden
| | - Daniel Thor
- Department of Clinical Science, Intervention and Technology at Karolinska Institutet, Division of Medical Imaging and Technology, Stockholm, Sweden
- Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm Sweden
| | - Michael A Fischer
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland
| | - Torkel Brismar
- Department of Clinical Science, Intervention and Technology at Karolinska Institutet, Division of Medical Imaging and Technology, Stockholm, Sweden
- Department of Radiology, Karolinska University Hospital in Huddinge, Stockholm, Sweden
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Zanardo M, Doniselli FM, Esseridou A, Tritella S, Mattiuz C, Menicagli L, Di Leo G, Sardanelli F. Abdominal CT: a radiologist-driven adjustment of the dose of iodinated contrast agent approaches a calculation per lean body weight. Eur Radiol Exp 2018; 2:41. [PMID: 30515613 PMCID: PMC6279751 DOI: 10.1186/s41747-018-0074-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Accepted: 10/19/2018] [Indexed: 11/10/2022] Open
Abstract
Background The contrast agent (CA) dose for abdominal computed tomography (CT) is typically based on patient total body weight (TBW), ignoring adipose tissue distribution. We report on our experience of dosing according to the lean body weight (LBW). Methods After Ethics Committee approval, we retrospectively screened 219 consecutive patients, 18 being excluded for not matching the inclusion criteria. Thus, 201 were analysed (106 males), all undergoing a contrast-enhanced abdominal CT with iopamidol (370 mgI/mL) or iomeprol (400 mgI/mL). LBW was estimated using validated formulas. Liver contrast-enhancement (CEL) was measured. Data were reported as mean ± standard deviation. Pearson correlation coefficient, ANOVA, and the Levene test were used. Results Mean age was 66 ± 13 years, TBW 72 ± 15 kg, LBW 53 ± 11 kg, and LBW/TBW ratio 74 ± 8%; body mass index was 26 ± 5 kg/m2, with 9 underweight patients (4%), 82 normal weight (41%), 76 overweight (38%), and 34 obese (17%). The administered CA dose was 0.46 ± 0.06 gI/kg of TBW, corresponding to 0.63 ± 0.09 gI/kg of LBW. A negative correlation was found between TBW and CA dose (r = -0.683, p < 0.001). CEL (Hounsfield units) was 51 ± 18 in underweight patients, 44 ± 8 in normal weight, 42 ± 9 in overweight, and 40 ± 6 in obese, with a significant difference for both mean (p = 0.004) and variance (p < 0.001). A low but significant positive correlation was found between CEL and CA dose in gI per TBW (r = 0.371, p < 0.001) or per LBW (r = 0.333, p < 0.001). Conclusions The injected CA dose was highly variable, with obese patients receiving a lower dose than underweight patients, as a radiologist-driven ‘compensation effect’. Diagnostic abdomen CT examinations may be obtained using 0.63 gI/kg of LBW.
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Affiliation(s)
- Moreno Zanardo
- PhD Course in Integrative Biomedical Research, Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133, Milan, Italy.
| | - Fabio Martino Doniselli
- Postgraduate School in Radiodiagnostics, Università degli Studi di Milano, Via Festa del Perdono 7, 20122, Milan, Italy
| | - Anastassia Esseridou
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
| | - Stefania Tritella
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
| | - Chiara Mattiuz
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
| | - Laura Menicagli
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
| | - Giovanni Di Leo
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy
| | - Francesco Sardanelli
- Radiology Unit, IRCCS Policlinico San Donato, Via Morandi 30, 20097, San Donato Milanese, Italy.,Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Morandi 30, 20097, San Donato Milanese, Italy
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Matsumoto Y, Higaki T, Masuda T, Sato T, Nakamura Y, Tatsugami F, Awai K. Minimizing individual variations in arterial enhancement on coronary CT angiographs using "contrast enhancement optimizer": a prospective randomized single-center study. Eur Radiol 2018; 29:2998-3005. [PMID: 30421021 DOI: 10.1007/s00330-018-5823-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 09/20/2018] [Accepted: 10/03/2018] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To investigate the clinical utility of our newly developed contrast enhancement optimizer (CEO) software for coronary CT angiography (CCTA). METHODS We randomly assigned 295 patients (168 males, 127 females, median age 71 years) undergoing CCTA to one of two contrast media injection protocols. Group A (n = 150) was injected with a CEO-selected iodine dose based on patient factors. In group B (n = 145), we used our standard protocol (245 mg I/kg). We recorded the CT number in the ascending aorta and determined whether the CT number was equivalent in groups A and B. For the equivalence test, we adopted 75 Hounsfield units (HU) as the equivalence margin. The standard deviation in the CT number and the rate of patients with an acceptable CT number were compared using the F test and the chi-square test, respectively. RESULTS The iodine dose in group A was significantly smaller than that in group B (235.7 vs. 253.6 mg I/kg, p < 0.001). The CT number of the ascending aorta was 428.6 ± 55.5 HU in group A and 436.1 ± 68.7 HU in group B; the 95% confidence interval for the difference between the groups was -4.3 HU to 16.9 HU and within the range of the predetermined equivalence margins. In group A, the variance was significantly smaller than that in group B (p = 0.009). The number of patients with an acceptable CT number was significantly higher in group A than in group B (84.7% vs. 71.7%, p = 0.007). CONCLUSIONS The use of our CEO for CCTA studies yielded optimal aortic contrast enhancement in significantly more patients than the standard protocol based on the body weight. KEY POINTS • With our contrast enhancement optimizer (CEO) software, optimal and stable aortic enhancement can be obtained on coronary CT angiography scans irrespective of patient factors. • Management of contrast media becomes more appropriate by the CEO software. • The CEO software can control contrast enhancement at different tube voltage levels.
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Affiliation(s)
- Yoriaki Matsumoto
- Department of Radiological Technology, Tsuchiya General Hospital, 3-30 Nakajima-cho, Naka-ku, Hiroshima, 730-8655, Japan. .,Department of Diagnostic Radiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan.
| | - Toru Higaki
- Department of Diagnostic Radiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Takanori Masuda
- Department of Radiological Technology, Tsuchiya General Hospital, 3-30 Nakajima-cho, Naka-ku, Hiroshima, 730-8655, Japan.,Department of Diagnostic Radiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Tomoyasu Sato
- Department of Radiology, Tsuchiya General Hospital, 3-30 Nakajima-cho, Naka-ku, Hiroshima, 730-8655, Japan
| | - Yuko Nakamura
- Department of Diagnostic Radiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Fuminari Tatsugami
- Department of Diagnostic Radiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Kazuo Awai
- Department of Diagnostic Radiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
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Abstract
OBJECTIVE The purpose of this article is to discuss the advances in CT acquisition and image postprocessing as they apply to imaging the pancreas and to conceptualize the role of radiogenomics and machine learning in pancreatic imaging. CONCLUSION CT is the preferred imaging modality for assessment of pancreatic diseases. Recent advances in CT (dual-energy CT, CT perfusion, CT volumetry, and radiogenomics) and emerging computational algorithms (machine learning) have the potential to further increase the value of CT in pancreatic imaging.
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Perrin E, Jackson M, Grant R, Lloyd C, Chinaka F, Goh V. Weight-adapted iodinated contrast media administration in abdomino-pelvic CT: Can image quality be maintained? Radiography (Lond) 2018; 24:22-27. [PMID: 29306370 DOI: 10.1016/j.radi.2017.08.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 08/23/2017] [Accepted: 08/31/2017] [Indexed: 10/18/2022]
Abstract
INTRODUCTION In many centres, a fixed method of contrast-media administration is used for CT regardless of patient body habitus. The aim of this trial was to assess contrast enhancement of the aorta, portal vein, liver and spleen during abdomino-pelvic CT imaging using a weight-adapted contrast media protocol compared to the current fixed dose method. METHODS Thirty-nine oncology patients, who had previously undergone CT abdomino-pelvic imaging at the institution using a fixed contrast media dose, were prospectively imaged using a weight-adapted contrast media dose (1.4 ml/kg). The two sets of images were assessed for contrast enhancement levels (HU) at locations in the liver, aorta, portal vein and spleen during portal-venous enhancement phase. The t-test was used to compare the difference in results using a non-inferiority margin of 10 HU. RESULTS When the contrast dose was tailored to patient weight, contrast enhancement levels were shown to be non-inferior to the fixed dose method (liver p < 0.001; portal vein p = 0.003; aorta p = 0.001; spleen p = 0.001). As a group, patients received a total contrast dose reduction of 165 ml using the weight-adapted method compared to the fixed dose method, with a mean cost per patient of £6.81 and £7.19 respectively. CONCLUSION Using a weight-adapted method of contrast media administration was shown to be non-inferior to a fixed dose method of contrast media administration. Patients weighing 76 kg, or less, received a lower contrast dose which may have associated cost savings. A weight-adapted contrast media protocol should be implemented for portal-venous phase abdomino-pelvic CT for oncology patients with adequate renal function (>70 ml/min/1.73 m2).
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Affiliation(s)
- E Perrin
- Guy's and St Thomas' NHS Foundation Trust, Great Maze Pond, London SE1 9RT, UK; St George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
| | - M Jackson
- St George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - R Grant
- St George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - C Lloyd
- Guy's and St Thomas' NHS Foundation Trust, Great Maze Pond, London SE1 9RT, UK
| | - F Chinaka
- Guy's and St Thomas' NHS Foundation Trust, Great Maze Pond, London SE1 9RT, UK
| | - V Goh
- Guy's and St Thomas' NHS Foundation Trust, Great Maze Pond, London SE1 9RT, UK
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Granata V, Fusco R, Catalano O, Setola SV, de Lutio di Castelguidone E, Piccirillo M, Palaia R, Grassi R, Granata F, Izzo F, Petrillo A. Multidetector computer tomography in the pancreatic adenocarcinoma assessment: an update. Infect Agent Cancer 2016; 11:57. [PMID: 27891175 PMCID: PMC5111267 DOI: 10.1186/s13027-016-0105-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 11/03/2016] [Indexed: 02/07/2023] Open
Abstract
Ductal adenocarcinoma of the pancreas is one of the most aggressive forms of cancer, with only a minority of cases being resectable at the moment of their diagnosis. The accurate detection and characterization of pancreatic carcinoma is very important for patient management. Multidetector-row computed tomography (MDCT) has become the cross-sectional modality of choice in the diagnosis, staging, treatment planning, and follow-up of patients with pancreatic tumors. However, approximately 11% of ductal adenocarcinomas still remain undetected at MDCT because of the lack of attenuation gradient between the lesion and the adjacent pancreatic parenchyma. In this systematic literature review we investigate the current evolution of the CT technique, limitations, and perspectives in the evaluation of pancreatic carcinoma.
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Affiliation(s)
- Vincenza Granata
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Roberta Fusco
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Orlando Catalano
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Sergio Venanzio Setola
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | | | - Mauro Piccirillo
- Department of Hepato-Biliary Surgery, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Raffaele Palaia
- Department of Hepato-Biliary Surgery, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Roberto Grassi
- Departement of Radiology, Seconda Università degli Studi di Napoli, Naples, Italy
| | - Francesco Granata
- Departement of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Lazio, Italy
| | - Francesco Izzo
- Department of Hepato-Biliary Surgery, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Antonella Petrillo
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
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Zhu L, Shi X, Xue H, Wu H, Chen G, Sun H, He Y, Jin Z, Liang Z, Zhang Z. CT Imaging Biomarkers Predict Clinical Outcomes After Pancreatic Cancer Surgery. Medicine (Baltimore) 2016; 95:e2664. [PMID: 26844495 PMCID: PMC4748912 DOI: 10.1097/md.0000000000002664] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
This study aimed to determine whether changes in contrast-enhanced computed tomography (CT) parameters could predict postsurgery overall and progression-free survival (PFS) in pancreatic cancer patients. Seventy-nine patients with a final pathological diagnosis of pancreatic adenocarcinoma were included in this study from June 2008 to August 2012. Dynamic contrast-enhanced (DCE) CT of tumors was obtained before curative-intent surgery. Absolute enhancement change (AEC) and relative enhancement change (REC) were evaluated on DCE-CT. PFS and overall survival (OS) were compared based on CT enhancement patterns. The markers of fibrogenic alpha-smooth muscle antigen (α-SMA) and periostin in tumor specimens were evaluated by immunohistochemical staining. The χ test was performed to determine whether CT enhancement patterns were associated with α-SMA-periostin expression levels (recorded as positive or negative). Lower REC (<0.9) was associated with shorter PFS (HR 0.51, 95% CI: 0.31-0.89) and OS (HR 0.44, 95% CI: 0.25-0.78). The α-SMA and periostin expression level were negatively correlated with REC (both P = 0). Among several CT enhancement parameters, REC was the best predictor of patient postsurgery survival. Low REC was associated with a short progression-free time and poor survival. The pathological studies suggested that REC might be a reflection of cancer fibrogenic potential.
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Affiliation(s)
- Liang Zhu
- From the Department of Radiology (LZ, HX, HS, YH, ZJ); Department of Pathology (XS, HW, ZL); Department of Surgery, Peking Union Medical College Hospital (GC), Beijing, China; Department of Radiology, Northwestern University, Chicago, IL (ZZ); and Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Pingjin Hospital Heart Center, Tianjin, China (ZZ)
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An Update of Clinical CT Imaging of Pancreatic Neoplasm: Tips, Tricks, and Pitfalls. CURRENT RADIOLOGY REPORTS 2015. [DOI: 10.1007/s40134-015-0104-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Koiwahara G, Tsuda T, Matsuda M, Hirata M, Tanaka H, Hyodo T, Kido T, Mochizuki T. Different enhancement of the hepatic parenchyma in dynamic CT for patients with normal liver and chronic liver diseases and with the dose of contrast medium based on body surface area. Jpn J Radiol 2015; 33:194-200. [PMID: 25673431 DOI: 10.1007/s11604-015-0398-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/26/2015] [Indexed: 12/11/2022]
Abstract
PURPOSE The purpose of this study was to characterize hepatic parenchymal enhancement for normal and diseased liver in dynamic computed tomography (CT) with the dose of contrast medium calculated on the basis of body surface area (BSA). MATERIALS AND METHODS The records of 328 consecutive patients who underwent triple-phase contrast-enhanced CT were retrospectively reviewed. The patients were divided into four groups: normal liver (n = 125), chronic hepatitis (CH) (n = 92), Child-Pugh grade A liver cirrhosis (LC-A) (n = 78), and Child-Pugh grade B liver cirrhosis (LC-B) (n = 33). All patients received 22 g I m(-2) as contrast material, calculated on the basis of BSA. CT values were measured in the region of interest during the pre-contrast, arterial, and portal phases, and the change in the CT value (ΔHU, where HU is Hounsfield units) compared with pre-contrast images was calculated. RESULTS Mean ΔHU for the hepatic parenchyma for the normal liver, CH, LC-A, and LC-B groups during the portal phase was 55.5 ± 11.8 HU, 55.2 ± 12.5 HU, 50.0 ± 13.0 HU, and 43.0 ± 12.7 HU, respectively; generalized estimating equation analysis showed the differences were significant (p < 0.01). CONCLUSION Hepatic parenchymal enhancement during the portal phase decreased as the severity of chronic liver damage increased.
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Affiliation(s)
- Gen Koiwahara
- Department of Radiology, Ehime University Graduate School of Medicine, 454 Shitukawa, Toon, Ehime, 791-0925, Japan,
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Adaptation of contrast injection protocol to tube potential for cardiovascular CT. AJR Am J Roentgenol 2014; 203:1181-91. [PMID: 25415695 DOI: 10.2214/ajr.13.12013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE The purpose of this study was to investigate and validate adaptation of a cardiovascular CT angiography contrast injection protocol for lower tube potential. MATERIALS AND METHODS Eighty-three patients evaluated for thoracic aortic disease with a 256-MDCT scanner were imaged at 120 kV (group 1) or 100 kV (group 2) with the same contrast protocol (90 mL iopromide 370 mg I/mL at 3.5 mL/s). A pharmacokinetic model was validated and used to simulate aortic attenuation in group 2 patients with 20%, 33%, and 44% reduction in contrast volume. A 44% volume reduction was applied to 50 additional patients who underwent imaging at 100 kV (group 3). Patient characteristics, scanning and radiation parameters, and objective and subjective image indexes were compared among groups. RESULTS Group 2 patients had higher mean aortic blood attenuation (399±61 HU) than group 1 patients (281±48 HU) (p<0.001) but similar image noise. Group 3 and group 1 patients had similar mean aortic attenuation and noise. Subjective assessment of image quality indicated that group 3 and group 1 had comparable percentages of images with good or excellent diagnostic confidence scores (reader 1, 98% vs 96%; reader 2, 96% vs 96%). CONCLUSION Lower tube potential (100 kV) for cardiothoracic CT could be accompanied by a 44% reduction in contrast volume with satisfactory aortic blood-pool attenuation in most patients. More personalized adaptation of the contrast protocol that takes into account patient characteristics and tube potential is necessary to ensure sufficient contrast enhancement for all patients.
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Tang A, Billiard JS, Chagnon DO, Rizk F, Olivié D, Turcotte S, Chagnon M, Lepanto L. Optimal Pancreatic Phase Delay with 64-Detector CT Scanner and Bolus-tracking Technique. Acad Radiol 2014; 21:977-85. [PMID: 25018069 DOI: 10.1016/j.acra.2014.04.004] [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: 01/30/2014] [Revised: 04/03/2014] [Accepted: 04/11/2014] [Indexed: 10/25/2022]
Abstract
RATIONALE AND OBJECTIVES To assess the optimal pancreatic phase delay in terms of parenchymal enhancement and tumor-to-pancreas contrast with a bolus-tracking method. MATERIALS AND METHODS Patients referred for suspicion of pancreatic tumor and undergoing 64-detector computed tomography scanner were randomized to an individualized scan delay of 10, 20, or 30 seconds of nonionic contrast material (370 mg I/mL) after aortic enhancement above 150 Hounsfield units. The volume of contrast was adjusted to patient weight. Pancreatic and tumor enhancements were measured. Statistical analysis included analysis of variance and post hoc Tukey tests. RESULTS One hundred and fifty patients were randomized to individualized scan delays of 10, 20, or 30 seconds. Pancreatic parenchymal enhancement in all patients (n = 150) was significantly higher with a delay of 20 or 30 seconds than that with 10 seconds (P < .001 for both). Tumor-to-pancreas contrast for solid tumors (n = 59) was significantly higher with a delay of 30 seconds than that with 10 seconds (P = .015). Adenocarcinoma-to-pancreas contrast during pancreatic phase was significantly higher for a 20- or 30-second delay than for a 10-second delay (P = .027 and .011, respectively) for one reader. CONCLUSIONS With a flow rate of 4 mL/s and weight-adjusted contrast volume, an individualized scan delay of 30 seconds after aortic transit time revealed higher pancreatic enhancement and tumor-to-pancreas contrast than that with a delay of 10 seconds.
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Svensson A, Björk J, Cederlund K, Aspelin P, Nyman U, Brismar TB. Automatic individualized contrast medium dosage during hepatic computed tomography by using computed tomography dose index volume (CTDI(vol)). Eur Radiol 2014; 24:1959-63. [PMID: 24859598 DOI: 10.1007/s00330-014-3220-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 04/08/2014] [Accepted: 05/06/2014] [Indexed: 11/24/2022]
Abstract
PURPOSE To compare hepatic parenchymal contrast media (CM) enhancement during multi-detector row computed tomography (MDCT) and its correlation with volume pitch-corrected computed tomography dose index CTDI(vol)) and body weight (BW). MATERIAL AND METHODS One hundred patients referred for standard three-phase thoraco-abdominal MDCT examination were enrolled. BW was measured in the CT suite. Forty grams of iodine was administered intravenously (iodixanol 320 mg I/ml at 5 ml/s or iomeprol 400 mg I/ml at 4 ml/s) followed by a 50-ml saline flush. CTDI(vol) presented by the CT equipment during the parenchymal examination was recorded. The CM enhancement of the liver was defined as the attenuation HU of the liver parenchyma during the hepatic parenchymal phase minus the attenuation in the native phase. RESULTS Liver parenchymal enhancement was negatively correlated to both CTDI(vol) (r = -0.60) and BW (r = -0.64), but the difference in correlation between those two was not significant. CONCLUSION CTDI(vol) may replace BW when adjusting CM doses to body size. This makes it potentially feasible to automatically individualize CM dosage by CT. KEY POINTS • CTDI vol is related to liver CM enhancement in the parenchymal phase. • CTDI vol provides comparable information to body weight (BW). • CTDI vol may be used when automatically adjusting CM dose for patient size.
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Affiliation(s)
- Anders Svensson
- Department of Clinical Science, Division of Medical Imaging and Technology, Intervention and Technology at Karolinska Institutet, Stockholm, Sweden,
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Patient body weight-tailored contrast medium injection protocol for the craniocervical vessels: a prospective computed tomography study. PLoS One 2014; 9:e88867. [PMID: 24558438 PMCID: PMC3928316 DOI: 10.1371/journal.pone.0088867] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 01/13/2014] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES To evaluate body weight-tailored contrast medium (CM) administration for computed tomography angiography (CTA) of the craniocervical vessels. METHODS Institutional review board approval was obtained, and all patients gave written informed consent. Sixty patients were consecutively assigned to one of three dose groups (20 patients per group) with CM doses of Visipaque 270® (iodixanol 270 mg/ml) tailored to body weight at doses of 1.5, 1.0, or 0.5 ml/kg. Region-of-interest (ROI) analysis of maximum enhancement (ME) was conducted, and signal-to-noise-ratios (SNR) and contrast-to-noise-ratios (CNR) were calculated. Retrospective comparison was performed with three matched control groups examined with a standard CM dose (80 ml of Visipaque 270®). Image quality was rated by two neuroradiologists blinded to the CM dose used. Interrater reliability was calculated using kappa statistics. RESULTS Body weight/BMI and ME were inversely correlated in the three control groups receiving the standard dose (r = -0.544/-0.597/-0.542/r = -0.358/r = -0.424/r = -0.280). Compared to standard dose, 1.5 ml/kg produced higher ME, SNR, and CNR in the anterior circulation (p≤0.038), 1.0 ml/kg had higher ME in cervical and medium-sized cerebral arteries (p≤0.034), and 0.5 ml/kg had lower ME, SNR and CNR for medium-sized cerebral arteries (p≤0.049). ME, SNR, and CNR were the same for 1.5 ml/kg and 1.0 ml/kg (p≥0.24), and both had higher values compared to 0.5 ml/kg (p≤0.043/p≤0.028). In patients with BMI>25, 1.5 ml/kg and 1.0 ml/kg produced higher ME than standard dose (p<0.001/p = 0.008), but ME in patients with BMI>25 did not differ between group 1 and group 2 (p = 0.673). In patients with BMI≤25, 1.5 ml/kg and 1.0 ml/kg produced ME comparable to standard dose (p = 0.132/p = 0.403). Regardless of patient weight, 0.5 ml/kg yielded lower ME than standard dose (p = 0.019/0.002). CONCLUSIONS Craniocervical CTA with a body weight-tailored CM dose of 1.0 ml/kg (270 mg iodine/ml) reduces iodine load in patients weighing <80 kg while producing ME similar to standard dose and improves ME in patients with BMI>25.
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Contrast medium injection protocol adjusted for body surface area in combined PET/CT. Eur Radiol 2013; 23:1970-7. [DOI: 10.1007/s00330-013-2781-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 12/21/2012] [Accepted: 01/06/2013] [Indexed: 10/27/2022]
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Chu AJ, Lee JM, Lee YJ, Moon SK, Han JK, Choi BI. Dual-source, dual-energy multidetector CT for the evaluation of pancreatic tumours. Br J Radiol 2012; 85:e891-8. [PMID: 22972978 DOI: 10.1259/bjr/26129418] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVE To investigate the potential diagnostic value of dual-energy CT (DECT) with virtual non-enhanced (VNE) and iodine-only images, and to determine the optimal mixed ratio of blended images for evaluation of pancreatic diseases. METHODS Multiphasic DECT was performed in 44 patients with focal pancreatic disease. DECT was used during the pancreatic and hepatic venous phases, and a peak kilovoltage of 120 kVp was used for both non-contrast phases. For qualitative analysis of the CT images, two radiologists assessed three image sets (VNE, iodine-only and blended images) in order to determine the acceptability of VNE in replacing true non-enhanced (TNE) images, the added value of iodine-only images and the preferred blending ratio. For quantitative analyses, the CT numbers and image noise of the pancreatic parenchyma, lesions, aorta and psoas muscle were measured. The contrast-to-noise ratio of the lesion was calculated on the pancreatic phase images. The effective radiation dose for DECT and TNE images was calculated. Statistical comparisons were made using the Friedman test, the Wilcoxon test, the paired t-test and repeated measures of analysis of variation with Bonferroni correction for multiple comparisons. RESULTS The level of acceptance of the VNE images in replacing TNE images was 90.9%. Regarding the iodine-only images, 50% of the cases were found to have an added value. The linear-blended images with a weighting factor of 0.5 were preferred. CONCLUSIONS DECT was able to provide high-quality VNE images that could replace TNE images and iodine-only images showing an added value. Blended images with a weighting factor of 0.5 were preferred by the reviewers.
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Affiliation(s)
- A J Chu
- Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea
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Svensson A, Nouhad J, Cederlund K, Aspelin P, Nyman U, Björk J, Torkel BB. Hepatic contrast medium enhancement at computed tomography and its correlation with various body size measures. Acta Radiol 2012; 53:601-6. [PMID: 22761344 DOI: 10.1258/ar.2012.120268] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND When the same dose of iodine is given to all patients when performing abdominal computed tomography (CT) there may be a wide inter-individual variation in contrast medium (CM) enhancement of the liver. PURPOSE To evaluate if any of the measures body height (BH), body mass index (BMI), lean body mass (LBM), ideal body weight (IBW), and body surface area (BSA) correlated better than body weight (BW) with hepatic enhancement, and to compare the enhancement when using iodixanol and iomeprol. MATERIAL AND METHODS One hundred patients referred for standard three-phase CT examination of abdomen were enrolled. Body weight and height were measured at the time of the CT examination. Forty grams of iodine (iodixanol 320 mg I/mL or iomeprol 400 mg I/mL) was injected at a rate of 1.6 g-I/s, followed by a 50 mL saline flush. The late arterial phase was determined by using a semi-automatic smart prep technique with a scan delay of 20 s. The hepatic parenchymal phase started automatically 25 s after the late arterial phase. CM concentration was estimated by placement of regions of interest in aorta (native and late arterial phase) and in liver (native and parenchymal phase). RESULTS BW (r = -0.51 and -0.64), LBM (r = -0.54 and -0.59), and BSA (r = -0.54 and -0.65) showed the best correlation coefficients with aortic and hepatic parenchymal enhancement, respectively, without any significant differences between the measures. Comparing iodixanol and iomeprol there was no significant difference in aortic enhancement. The liver enhancement was significantly higher (P < 0.05) using iodixanol than iomeprol. CONCLUSION To achieve a consistent hepatic enhancement, CM dose may simply be adjusted to body weight instead of using more complicated calculated parameters based on both weight and height.
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Affiliation(s)
- Anders Svensson
- Department of Clinical Science, Intervention and Technology at Karolinska Institutte, Division of Medical Imaging and Technology, Stockholm, Sweden and Department of Radiology, Karolinska University Hospital, Huddinge, Stockholm
| | - Jallo Nouhad
- Department of Clinical Science, Intervention and Technology at Karolinska Institutte, Division of Medical Imaging and Technology, Stockholm, Sweden and Department of Radiology, Karolinska University Hospital, Huddinge, Stockholm
| | - Kerstin Cederlund
- Department of Clinical Science, Intervention and Technology at Karolinska Institutte, Division of Medical Imaging and Technology, Stockholm, Sweden and Department of Radiology, Karolinska University Hospital, Huddinge, Stockholm
| | - Peter Aspelin
- Department of Clinical Science, Intervention and Technology at Karolinska Institutte, Division of Medical Imaging and Technology, Stockholm, Sweden and Department of Radiology, Karolinska University Hospital, Huddinge, Stockholm
| | - Ulf Nyman
- Department of Diagnostic Radiology, Lasarettet Trelleborg, University of Lund, Trelleborg
| | - Jonas Björk
- Competence Centre for Clinical Research, Skåne University Hospital, Lund, Sweden
| | - Brismar B Torkel
- Department of Clinical Science, Intervention and Technology at Karolinska Institutte, Division of Medical Imaging and Technology, Stockholm, Sweden and Department of Radiology, Karolinska University Hospital, Huddinge, Stockholm
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Abstract
Multidetector-row CT (MDCT) imaging of the pancreas has important roles in diagnosis, staging, and treatment monitoring of a vast array of pancreatic diseases. Optimizing MDCT protocols not only requires an understanding of expected pathologies but also must take into account cumulative radiation dose considerations.
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Balthazar EJ. CT contrast enhancement of the pancreas: patterns of enhancement, pitfalls and clinical implications. Pancreatology 2012; 11:585-7. [PMID: 22237258 DOI: 10.1159/000335130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Long XY, Sun WJ, Zou YY, Li YX. Imaging evaluation of therapeutic response in patients with pancreatic cancer: recent advances. Shijie Huaren Xiaohua Zazhi 2011; 19:1211-1218. [DOI: 10.11569/wcjd.v19.i12.1211] [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] [Indexed: 02/06/2023] Open
Abstract
Chemoradiotherapy is the primary choice of non-surgical treatment of advanced pancreatic cancer, and diagnostic imaging plays an important role in objectively assessing early therapeutic response. This article systematically reviews the criteria for evaluation of therapeutic response in solid tumors and their application in pancreatic cancer, highlighting some key contents in imaging evaluation of therapeutic response in patients with pancreatic cancer.
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Yoon SH, Lee JM, Cho JY, Lee KB, Kim JE, Moon SK, Kim SJ, Baek JH, Kim SH, Kim SH, Lee JY, Han JK, Choi BI. Small (≤ 20 mm) pancreatic adenocarcinomas: analysis of enhancement patterns and secondary signs with multiphasic multidetector CT. Radiology 2011; 259:442-52. [PMID: 21406627 DOI: 10.1148/radiol.11101133] [Citation(s) in RCA: 163] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE To evaluate the enhancement patterns, prevalence of secondary signs, and histopathologic features of 20-mm-diameter or smaller pancreatic cancers seen on multiphasic multidetector computed tomographic (CT) images. MATERIALS AND METHODS This retrospective study was approved by the institutional review board; the requirement for informed consent was waived. From January 2002 through September 2009, the authors reviewed the clinical and imaging data of 130 consecutive patients (76 men, 54 women; mean age, 64.1 years; age range, 28-82 years) who had surgically proven 30-mm-diameter or smaller pancreatic cancers and underwent preoperative multidetector CT and 33 consecutive patients (17 men, 16 women; mean age, 65.1 years; age range, 48-84 years) who had histopathologically proven pancreatic cancer and underwent incidental multidetector CT before the diagnosis was rendered. Only pancreatic phase CT was performed in two patients, and only hepatic venous phase CT was performed in nine patients. Two radiologists in consensus classified the tumor attenuation as hyper-, iso-, or hypoattenuation during the pancreatic and hepatic venous phases. Accompanying secondary signs, temporal changes in tumor attenuation, and histopathologic findings also were analyzed. The Fisher exact test, χ(2) test, generalized estimating equation, and Student t test were used to compare the variables. RESULTS Seventy tumors were 20 mm or smaller, and 93 were 21-30 mm. Isoattenuating pancreatic cancers were more commonly observed among the 20-mm or smaller tumors (16 of 59, 27%) than among the 21-30-mm tumors (12 of 93, 13%) (P = .033). They were also more common among well-differentiated tumors (seven of 12, 58%) than among moderately differentiated (20 of 124, 16%) and poorly differentiated (one of 10, 10%) tumors (P = .001). The prevalence of secondary signs differed significantly according to tumor size (53 [76%] of 70 ≤20-mm tumors vs 92 [99%] of 93 21-30-mm tumors) (P < .001). The prevalence of secondary signs was high among isoattenuating pancreatic cancers (14 [88%] of 16 ≤20-mm tumors vs all 12 [100%] 21-30-mm tumors). Most of the isoattenuating tumors seen at prediagnostic CT were hypoattenuating after 6 months (100% [four of four] during pancreatic phase, 71% [five of seven] during hepatic venous phase). CONCLUSION The prevalence of isoattenuating pancreatic cancers differed significantly according to tumor size and cellular differentiation. Most small isoattenuating pancreatic cancers showed secondary signs. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101133/-/DC1.
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Affiliation(s)
- Soon Ho Yoon
- Department of Radiology, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea
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An optimal contrast dose indicator for the determination of hepatic enhancement in abdominal multidetector computed tomography: comparison of patient attenuation indicator with total body weight and body mass index. J Comput Assist Tomogr 2010; 34:874-8. [PMID: 21084903 DOI: 10.1097/rct.0b013e3181ed2f72] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate a patient attenuation indicator (PAI) as compared with traditional patient-related factors of total body weight and body mass index (BMI) as a predictor of hepatic enhancement in contrast-enhanced abdominal multidetector computed tomography (MDCT). MATERIALS AND METHODS Institutional review board approval was obtained, and the study was Health Insurance Portability and Accountability Act compliant. A total of 77 patients (mean age, 53 years; male-female ratio, 32:45) underwent routine contrast-enhanced abdominal CT on a 16-slice multidetector CT (LightSpeed 16; GE Medical Systems, Milwaukee, Wis). Contrast enhancement was achieved by administering a 120-mL iodine contrast medium (350-mg iodine per milliliter) at an injection rate of 3 mL/s followed by an injection of 40-mL saline at 3 mL/s. Computed tomographic attenuation values (Hounsfield units [HU]) of liver parenchyma, main portal vein, and abdominal aorta were measured in each patient. Statistical analysis was performed with linear regression to determine the correlation of PAI, total body weight, and BMI with abdominal organ enhancement. RESULTS The mean of PAI, total body weight, and BMI were 28.0 (range, 22.1-34.2), 79.0 kg (range, 49.6-112.2 kg), and 27.5 kg/m (range, 16.8-43 kg/m), respectively. Mean hepatic enhancement was 128.2 HU (range, 73.6-175 HU), mean main portal vein enhancement was 214.2 HU (range, 118-327 HU), and mean abdominal aorta enhancement was 208.9 HU (range, 116-395 HU). Patient attenuation indicator, total body weight, and BMI showed a negative correlation with liver enhancement (r = -0.55, r = -0.4, and r = -0.3, respectively). Patient attenuation indicator exhibited a significantly higher correlation with hepatic enhancement than total body weight and BMI (P < 0.01, respectively). CONCLUSIONS Patient attenuation indicator exhibits a moderately inverse correlation with liver enhancement that is greater than those of total body weight and BMI. Patient attenuation indicator may be reliable in predicting the hepatic enhancement degree for a given dose of contrast material and has a potential use in customizing individual patient contrast medium dose during contrast-enhanced abdominal CT.
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Rudloff U, Maker AV, Brennan MF, Allen PJ. Randomized Clinical Trials in Pancreatic Adenocarcinoma. Surg Oncol Clin N Am 2010; 19:115-50. [DOI: 10.1016/j.soc.2009.09.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Pancreatic adenocarcinoma: a comparison of automatic bolus tracking and empirical scan delay. ACTA ACUST UNITED AC 2009; 35:548-55. [DOI: 10.1007/s00261-009-9560-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2008] [Revised: 04/13/2009] [Accepted: 06/23/2009] [Indexed: 10/20/2022]
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Behrendt FF, Plumhans C, Keil S, Mühlenbruch G, Das M, Seidensticker P, Mutscher C, Günther RW, Mahnken AH. Contrast enhancement in chest multidetector computed tomography: intraindividual comparison of 300 mg/ml versus 400 mg/ml iodinated contrast medium. Acad Radiol 2009; 16:144-9. [PMID: 19124099 DOI: 10.1016/j.acra.2008.05.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 04/30/2008] [Accepted: 05/02/2008] [Indexed: 11/19/2022]
Abstract
RATIONALE AND OBJECTIVES We sought to intraindividually compare intravascular contrast enhancement in multidector computed tomography (MDCT) of the chest using contrast media (CM) containing 300 and 400 mg iodine/ml. MATERIALS AND METHODS Seventy-one patients underwent repeated MDCT scanning of the chest at baseline and follow-up. CM with standard iodine (protocol A: 300 mg iodine/ml; Iopromide 300) and high iodine concentration (protocol B: 400 mg iodine/ml; Iomeprol 400) were used. The iodine delivery rate (1.29 g iodine/s) and total iodine load (37 g iodine) were identical for the two protocols. Contrast enhancement was measured in the right and left ventricles, pulmonary trunk, right and left pulmonary arteries, and ascending and descending aortas. Results were compared using paired t-tests; P values were adjusted using Bonferroni correction (P <or= .005). RESULTS Contrast enhancement values showed no statistically significant differences between the two protocols at all anatomic sites (all P > .005). In the right ventricle, pulmonary trunk, and right and left pulmonary arteries, higher attenuation values for protocol A were detected compared to protocol B (379.0 +/- 110.5 vs. 349.8 +/- 117.6, 354.5 +/- 112.2 vs 330.9 +/- 118.3, 348.6 +/- 106.0 vs. 321.8 +/- 109.9, and 347.9 +/- 102.4 vs. 321.0 +/- 104.9 HU, respectively). After the lung circulation (left ventricle, ascending aorta, and descending aorta), attenuation values were marginally higher for protocol B. Using both protocols resulted in suitable contrast enhancement with a mean pulmonary attenuation higher than 300 HU. CONCLUSIONS Using an adapted injection protocol, the administration of 300 and 400 mg iodine CM resulted in a suitable intravascular contrast enhancement in the chest. The use of 400 mg iodine CM does not lead to a statistically significant improvement in contrast enhancement compared to the 300 mg iodine CM.
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Affiliation(s)
- Florian F Behrendt
- Department of Diagnostic Radiology, University Hospital RWTH Aachen, Aachen, Germany.
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Fleischmann D, Kamaya A. Optimal Vascular and Parenchymal Contrast Enhancement: The Current State of the Art. Radiol Clin North Am 2009; 47:13-26. [DOI: 10.1016/j.rcl.2008.10.009] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Aortic and hepatic contrast enhancement with abdominal 64-MDCT in pediatric patients: effect of body weight and iodine dose. AJR Am J Roentgenol 2008; 191:1589-94. [PMID: 18941106 DOI: 10.2214/ajr.07.3576] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of our study was to retrospectively evaluate the effect of body weight and iodine dose on aortic and hepatic contrast enhancement in pediatric patients who underwent 64-MDCT of the abdomen and pelvis. MATERIALS AND METHODS Eighty-seven consecutive pediatric patients (50 boys and 37 girls; median age, 12.1 years; age range, 3.8-17.6 years) underwent standard abdominopelvic CT with a 64-MDCT scanner. Contrast medium (350 mg I/mL) was injected using a power injector at 2 mL/s followed by 15-20 mL of saline flush. According to our CT protocol, the volume of administered contrast medium was approximately 1.8 mL/kg of body weight, up to the maximum volume of 80 mL. CT scanning was initiated 60 seconds after the start of the contrast medium injection. CT attenuations of the aorta and liver were measured. For each patient, the injected contrast medium iodine mass per body weight index (g I/kg) (hereafter, iodine mass body index) was calculated. Linear regression analysis was performed between iodine mass body index and aortic and hepatic attenuations. RESULTS A wide range of patient weights (19-82 kg; mean, 48.6 kg [95% CI, 45.3-51.9 kg]) and contrast volumes (30-80 mL; median, 80.0 mL) were observed. The median attenuations were 149.0 HU (141.0-160.0 HU) for the aorta and 113.5 HU (109.5-120.0 HU) for the liver. Moderately high correlations were observed between iodine mass body index and aortic (Spearman's rho [r(s)] = 0.60 [0.45-0.72]; p < 0.001) and hepatic (r(s) = 0.60 [0.42-0.70]; p < 0.001) attenuations. The regression formulae for aortic attenuation (58.4 + 176.3 x iodine mass body index [p < 0.001]) and hepatic attenuation (58.7 + 108.5 x iodine mass body index [p < 0.001]) indicate that 1.5 and 1.8 mL/kg (350 mg I/mL) of contrast media are required to achieve 116 and 127 HU, respectively, of contrast-enhanced attenuation in the liver. CONCLUSION In our study, using abdominal 64-MDCT in pediatric patients, we found that approximately 1.5 mL/kg, or 0.525 g I/kg, yields 116 HU of hepatic attenuation or 50-55 HU of hepatic enhancement.
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Introduction of a Dedicated Circulation Phantom for Comprehensive In Vitro Analysis of Intravascular Contrast Material Application. Invest Radiol 2008; 43:729-36. [DOI: 10.1097/rli.0b013e318182267e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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