76 research outputs found

    Systematic evaluation of radiological findings in the assessment of resectability of peri-ampullary cancer by CT using different contrast phase protocols

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    Aims: To determine the relative significance of radiological signs in determining the resectability of peri-ampullary cancer (PC) and to assess the value of multi-phase imaging in detecting these findings. Materials and Methods: Blinded, double re-reporting of pre-operative imaging from five hospitals was undertaken of 411 patients undergoing surgery for PC over an eight year period, of whom 119 patients were found to be inoperable at the time of surgery. Results: The median tumour size was 26.7 mm and the proportion of patients reported to have regional lymphadenopathy (RL), venous (VI) and arterial involvement (AI) was 24.7%, 11.5% and 3.9% respectively and was similar regardless of the number of contrast phases undertaken. Significant associations were however noted between individual risk factors: VI was closely associated with tumour size (p=0.002) and AI (p< 0.0001). In multi-variable analysis AI, VI and RL were independently associated with resectability (relative risk of resection =0.05, 0.31 and 0.51 respectively). Tumour size however was not associated with resectability when VI was included in the multivariate model

    A methodology review on the incremental prognostic value of computed tomography biomarkers in addition to Framingham risk score in predicting cardiovascular disease: the use of association, discrimination and reclassification

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    This is the final version of the article. Available from the publisher via the DOI in this record.BACKGROUND: Computed tomography (CT) biomarkers claim to improve cardiovascular risk stratification. This review focuses on significant differences in incremental measures between adequate and inadequate reporting practise. METHODS: Studies included were those that used Framingham Risk Score as a baseline and described the incremental value of adding calcium score or CT coronary angiogram in predicting cardiovascular risk. Searches of MEDLINE, EMBASE, Web of Science and Cochrane Central were performed with no language restriction. RESULTS: Thirty five studies consisting of 206,663 patients (men = 118,114, 55.1%) were included. The baseline Framingham Risk Score included the 1998, 2002 and 2008 iterations. Selective reporting, inconsistent reference groupings and thresholds were found. Twelve studies (34.3%) had major and 23 (65.7%) had minor alterations and the respective Δ AUC were significantly different (p = 0.015). When the baseline model performed well, the Δ AUC was relatively lower with the addition of a CT biomarker (Spearman coefficient = − 0.46, p < 0.0001; n = 33; 76 pairs of data). Other factors that influenced AUC performance included exploration of data analysis, calibration, validation, multivariable and AUC documentation (all p < 0.05). Most studies (68.7%) that reported categorical NRI (n = 16; 46 pairs of data) subjectively drew strong conclusions along with other poor reporting practices. However, no significant difference in values of NRI was found between adequate and inadequate reporting. CONCLUSIONS: The widespread practice of poor reporting particularly association, discrimination, reclassification, calibration and validation undermines the claimed incremental value of CT biomarkers over the Framingham Risk Score alone. Inadequate reporting of discrimination inflates effect estimate, however, that is not necessarily the case for reclassification.This research was funded by the National Insitute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula (NIHR CLAHRC South West Peninsula)

    Computational instantaneous wave‐free ratio (IFR) for patient‐specific coronary artery stenoses using 1D network models

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    In this work, we estimate the diagnostic threshold of the instantaneous wave‐free ratio (iFR) through the use of a one‐dimensional haemodynamic framework. To this end, we first compared the computed fractional flow reserve (cFFR) predicted from a 1D computational framework with invasive clinical measurements. The framework shows excellent promise and utilises minimal patient data from a cohort of 52 patients with a total of 66 stenoses. The diagnostic accuracy of the cFFR model was 75.76%, with a sensitivity of 71.43%, a specificity of 77.78%, a positive predictive value of 60%, and a negative predictive value of 85.37%. The validated model was then used to estimate the diagnostic threshold of iFR. The model determined a quadratic relationship between cFFR and the ciFR. The iFR diagnostic threshold was determined to be 0.8910 from a receiver operating characteristic curve that is in the range of 0.89 to 0.9 that is normally reported in clinical studies

    Prospective intra-individual comparison of standard dose versus reduced-dose thoracic CT using hybrid and pure iterative reconstruction in a follow-up cohort of pulmonary nodules—Effect of detectability of pulmonary nodules with lowering dose based on nodule size, type and body mass index

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    publisher: Elsevier articletitle: Prospective intra-individual comparison of standard dose versus reduced-dose thoracic CT using hybrid and pure iterative reconstruction in a follow-up cohort of pulmonary nodules—Effect of detectability of pulmonary nodules with lowering dose based on nodule size, type and body mass index journaltitle: European Journal of Radiology articlelink: http://dx.doi.org/10.1016/j.ejrad.2017.04.006 content_type: article copyright: © 2017 Elsevier B.V. All rights reserved

    Early computed tomography coronary angiography in adults presenting with suspected acute coronary syndrome: the RAPID-CTCA RCT.

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    BACKGROUND: Acute coronary syndrome is a common medical emergency. The optimal strategy to investigate patients who are at intermediate risk of acute coronary syndrome has not been fully determined. OBJECTIVE: To investigate the role of early computed tomography coronary angiography in the investigation and treatment of adults presenting with suspected acute coronary syndrome. DESIGN: A prospective, multicentre, open, parallel-group randomised controlled trial with blinded end-point adjudication. SETTING: Thirty-seven hospitals in the UK. PARTICIPANTS: Adults (aged ≥ 18 years) presenting to the emergency department, acute medicine services or cardiology department with suspected or provisionally diagnosed acute coronary syndrome and at least one of the following: (1) a prior history of coronary artery disease, (2) a cardiac troponin level > 99th centile and (3) an abnormal 12-lead electrocardiogram. INTERVENTIONS: Early computed tomography coronary angiography in addition to standard care was compared with standard care alone. Participants were followed up for 1 year. MAIN OUTCOME MEASURE: One-year all-cause death or subsequent type 1 (spontaneous) or type 4b (stent thrombosis) myocardial infarction, measured as the time to such event adjudicated by two cardiologists blinded to the computerised tomography coronary angiography ( CTCA ) arm. Cost-effectiveness was estimated as the lifetime incremental cost per quality-adjusted life-year gained. RESULTS: Between 23 March 2015 and 27 June 2019, 1748 participants [mean age 62 years (standard deviation 13 years), 64% male, mean Global Registry Of Acute Coronary Events score 115 (standard deviation 35)] were randomised to receive early computed tomography coronary angiography (n = 877) or standard care alone (n = 871). The primary end point occurred in 51 (5.8%) participants randomised to receive computed tomography coronary angiography and 53 (6.1%) participants randomised to receive standard care (adjusted hazard ratio 0.91, 95% confidence interval 0.62 to 1.35; p = 0.65). Computed tomography coronary angiography was associated with a reduced use of invasive coronary angiography (adjusted hazard ratio 0.81, 95% confidence interval 0.72 to 0.92; p = 0.001) but no change in coronary revascularisation (adjusted hazard ratio 1.03, 95% confidence interval 0.87 to 1.21; p = 0.76), acute coronary syndrome therapies (adjusted odds ratio 1.06, 95% confidence interval 0.85 to 1.32; p = 0.63) or preventative therapies on discharge (adjusted odds ratio 1.07, 95% confidence interval 0.87 to 1.32; p = 0.52). Early computed tomography coronary angiography was associated with longer hospitalisations (median increase 0.21 days, 95% confidence interval 0.05 to 0.40 days) and higher mean total health-care costs over 1 year (£561 more per patient) than standard care. LIMITATIONS: The principal limitation of the trial was the slower than anticipated recruitment, leading to a revised sample size, and the requirement to compromise and accept a larger relative effect size estimate for the trial intervention. FUTURE WORK: The potential role of computed tomography coronary angiography in selected patients with a low probability of obstructive coronary artery disease (intermediate or mildly elevated level of troponin) or who have limited access to invasive cardiac catheterisation facilities needs further prospective evaluation. CONCLUSIONS: In patients with suspected or provisionally diagnosed acute coronary syndrome, computed tomography coronary angiography did not alter overall coronary therapeutic interventions or 1-year clinical outcomes, but it did increase the length of hospital stay and health-care costs. These findings do not support the routine use of early computed tomography coronary angiography in intermediate-risk patients with acute chest pain. TRIAL REGISTRATION: This trial is registered as ISRCTN19102565 and Clinical Trials NCT02284191. FUNDING: This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 37. See the NIHR Journals Library website for further project information

    Recommendations for accurate CT diagnosis of suspected acute aortic syndrome (AAS)-on behalf of the British Society of Cardiovascular Imaging (BSCI)/British Society of Cardiovascular CT (BSCCT)

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    Accurate and timely assessment of suspected acute aortic syndrome is crucial in this life-threatening condition. Imaging with CT plays a central role in the diagnosis to allow expedited management. Diagnosis can be made using locally available expertise with optimized scanning parameters, making full use of recent advances in CT technology. Each imaging centre must optimize their protocols to allow accurate diagnosis, to optimize radiation dose and in particular to reduce the risk of false-positive diagnosis that may simulate disease. This document outlines the principles for the acquisition of motion-free imaging of the aorta in this context.published_or_final_versio

    Early computed tomography coronary angiography in adults presenting with suspected acute coronary syndrome:the RAPID-CTCA RCT

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    Abstract Background Acute coronary syndrome is a common medical emergency. The optimal strategy to investigate patients who are at intermediate risk of acute coronary syndrome has not been fully determined. Objective To investigate the role of early computed tomography coronary angiography in the investigation and treatment of adults presenting with suspected acute coronary syndrome. Design A prospective, multicentre, open, parallel-group randomised controlled trial with blinded end-point adjudication. Setting Thirty-seven hospitals in the UK. Participants Adults (aged ≥ 18 years) presenting to the emergency department, acute medicine services or cardiology department with suspected or provisionally diagnosed acute coronary syndrome and at least one of the following: (1) a prior history of coronary artery disease, (2) a cardiac troponin level > 99th centile and (3) an abnormal 12-lead electrocardiogram. Interventions Early computed tomography coronary angiography in addition to standard care was compared with standard care alone. Participants were followed up for 1 year. Main outcome measure One-year all-cause death or subsequent type 1 (spontaneous) or type 4b (stent thrombosis) myocardial infarction, measured as the time to such event adjudicated by two cardiologists blinded to the computerised tomography coronary angiography (CTCA) arm. Cost-effectiveness was estimated as the lifetime incremental cost per quality-adjusted life-year gained. Results Between 23 March 2015 and 27 June 2019, 1748 participants [mean age 62 years (standard deviation 13 years), 64% male, mean Global Registry Of Acute Coronary Events score 115 (standard deviation 35)] were randomised to receive early computed tomography coronary angiography (n = 877) or standard care alone (n = 871). The primary end point occurred in 51 (5.8%) participants randomised to receive computed tomography coronary angiography and 53 (6.1%) participants randomised to receive standard care (adjusted hazard ratio 0.91, 95% confidence interval 0.62 to 1.35; p = 0.65). Computed tomography coronary angiography was associated with a reduced use of invasive coronary angiography (adjusted hazard ratio 0.81, 95% confidence interval 0.72 to 0.92; p = 0.001) but no change in coronary revascularisation (adjusted hazard ratio 1.03, 95% confidence interval 0.87 to 1.21; p = 0.76), acute coronary syndrome therapies (adjusted odds ratio 1.06, 95% confidence interval 0.85 to 1.32; p = 0.63) or preventative therapies on discharge (adjusted odds ratio 1.07, 95% confidence interval 0.87 to 1.32; p = 0.52). Early computed tomography coronary angiography was associated with longer hospitalisations (median increase 0.21 days, 95% confidence interval 0.05 to 0.40 days) and higher mean total health-care costs over 1 year (£561 more per patient) than standard care. Limitations The principal limitation of the trial was the slower than anticipated recruitment, leading to a revised sample size, and the requirement to compromise and accept a larger relative effect size estimate for the trial intervention. Future work The potential role of computed tomography coronary angiography in selected patients with a low probability of obstructive coronary artery disease (intermediate or mildly elevated level of troponin) or who have limited access to invasive cardiac catheterisation facilities needs further prospective evaluation. Conclusions In patients with suspected or provisionally diagnosed acute coronary syndrome, computed tomography coronary angiography did not alter overall coronary therapeutic interventions or 1-year clinical outcomes, but it did increase the length of hospital stay and health-care costs. These findings do not support the routine use of early computed tomography coronary angiography in intermediate-risk patients with acute chest pain
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