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  1. Article ; Online: A further explanation for chest pain without visible coronary artery disease.

    Newman, Tom / Morris, Paul / Gunn, Julian

    Clinical medicine (London, England)

    2021  Volume 21, Issue 2, Page(s) e242

    MeSH term(s) Chest Pain/etiology ; Coronary Angiography ; Coronary Artery Disease ; Humans
    Language English
    Publishing date 2021-03-24
    Publishing country England
    Document type Letter ; Comment
    ZDB-ID 2048646-7
    ISSN 1473-4893 ; 1470-2118
    ISSN (online) 1473-4893
    ISSN 1470-2118
    DOI 10.7861/clinmed.Let.21.2.3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online: Cycle Road Racing

    Newman, Tom

    2013  

    Abstract: Cycle Road Racing provides a practical and instructional guide for those entering into cycle road racing, and those improving their performance. It covers the latest developments in racing and cycle technology, and guides the reader through all stages ... ...

    Abstract Cycle Road Racing provides a practical and instructional guide for those entering into cycle road racing, and those improving their performance. It covers the latest developments in racing and cycle technology, and guides the reader through all stages of racing, from setting up the bike correctly to race day itself.The book includes material on: Clothing, equipment and setting up your bike; Training, including the use of turbo training in winter and sample training plans; Techniques such as cornering, climbing and descending; Avoiding injury and recovery after injury; Nutrition.In-depth
    Language English
    Size Online-Ressource (284 p)
    Publisher Crowood
    Publishing place Ramsbury
    Document type Book ; Online
    Note Description based upon print version of record
    ISBN 9781847974341 ; 1847974341
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  3. Article ; Online: Evaluation of models of sequestration flow in coronary arteries-Physiology versus anatomy?

    Taylor, Daniel J / Saxton, Harry / Halliday, Ian / Newman, Tom / Feher, Jeroen / Gosling, Rebecca / Narracott, Andrew J / van Kemenade, Denise / Van't Veer, Marcel / Tonino, Pim A L / Rochette, Michel / Hose, D Rodney / Gunn, Julian P / Morris, Paul D

    Computers in biology and medicine

    2024  Volume 173, Page(s) 108299

    Abstract: Background: Myocardial ischaemia results from insufficient coronary blood flow. Computed virtual fractional flow reserve (vFFR) allows quantification of proportional flow loss without the need for invasive pressure-wire testing. In the current study, we ...

    Abstract Background: Myocardial ischaemia results from insufficient coronary blood flow. Computed virtual fractional flow reserve (vFFR) allows quantification of proportional flow loss without the need for invasive pressure-wire testing. In the current study, we describe a novel, conductivity model of side branch flow, referred to as 'leak'. This leak model is a function of taper and local pressure, the latter of which may change radically when focal disease is present. This builds upon previous techniques, which either ignore side branch flow, or rely purely on anatomical factors. This study aimed to describe a new, conductivity model of side branch flow and compare this with established anatomical models.
    Methods and results: The novel technique was used to quantify vFFR, distal absolute flow (Qd) and microvascular resistance (CMVR) in 325 idealised 1D models of coronary arteries, modelled from invasive clinical data. Outputs were compared to an established anatomical model of flow. The conductivity model correlated and agreed with the reference model for vFFR (r = 0.895, p < 0.0001; +0.02, 95% CI 0.00 to + 0.22), Qd (r = 0.959, p < 0.0001; -5.2 mL/min, 95% CI -52.2 to +13.0) and CMVR (r = 0.624, p < 0.0001; +50 Woods Units, 95% CI -325 to +2549).
    Conclusion: Agreement between the two techniques was closest for vFFR, with greater proportional differences seen for Qd and CMVR. The conductivity function assumes vessel taper was optimised for the healthy state and that CMVR was not affected by local disease. The latter may be addressed with further refinement of the technique or inferred from complementary image data. The conductivity technique may represent a refinement of current techniques for modelling coronary side-branch flow. Further work is needed to validate the technique against invasive clinical data.
    MeSH term(s) Humans ; Coronary Vessels ; Coronary Angiography/methods ; Fractional Flow Reserve, Myocardial ; Coronary Artery Disease ; Hemodynamics ; Coronary Stenosis ; Predictive Value of Tests
    Language English
    Publishing date 2024-03-18
    Publishing country United States
    Document type Journal Article
    ZDB-ID 127557-4
    ISSN 1879-0534 ; 0010-4825
    ISSN (online) 1879-0534
    ISSN 0010-4825
    DOI 10.1016/j.compbiomed.2024.108299
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Sex differences in coronary microvascular resistance measured by a computational fluid dynamics model.

    Taylor, Daniel J / Aubiniere-Robb, Louise / Gosling, Rebecca / Newman, Tom / Hose, D Rodney / Halliday, Ian / Lawford, Patricia V / Narracott, Andrew J / Gunn, Julian P / Morris, Paul D

    Frontiers in cardiovascular medicine

    2023  Volume 10, Page(s) 1159160

    Abstract: Background: Increased coronary microvascular resistance (CMVR) is associated with coronary microvascular dysfunction (CMD). Although CMD is more common in women, sex-specific differences in CMVR have not been demonstrated previously.: Aim: To compare ...

    Abstract Background: Increased coronary microvascular resistance (CMVR) is associated with coronary microvascular dysfunction (CMD). Although CMD is more common in women, sex-specific differences in CMVR have not been demonstrated previously.
    Aim: To compare CMVR between men and women being investigated for chest pain.
    Methods and results: We used a computational fluid dynamics (CFD) model of human coronary physiology to calculate absolute CMVR based on invasive coronary angiographic images and pressures in 203 coronary arteries from 144 individual patients. CMVR was significantly higher in women than men (860 [650-1,205] vs. 680 [520-865] WU,
    Conclusion: CMVR was significantly higher in women compared with men. These sex-specific differences may help to explain the increased prevalence of CMD in women.
    Language English
    Publishing date 2023-07-06
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2781496-8
    ISSN 2297-055X
    ISSN 2297-055X
    DOI 10.3389/fcvm.2023.1159160
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: The Complementary Value of Absolute Coronary Flow in the Assessment of Patients with Ischaemic Heart Disease (the COMPAC-Flow Study).

    Aubiniere-Robb, Louise / Gosling, Rebecca / Taylor, Daniel J / Newman, Tom / Rodney, D / Ian Halliday, Hose / Lawford, Patricia V / Narracott, Andrew J / Gunn, Julian P / Morris, Paul D

    Nature cardiovascular research

    2022  Volume 1, Issue 7, Page(s) 611–616

    Abstract: Fractional flow reserve (FFR) is the current gold-standard invasive assessment of coronary artery disease (CAD). FFR reports coronary blood flow (CBF) as a fraction of a hypothetical and unknown normal value. Although used routinely to diagnose CAD and ... ...

    Abstract Fractional flow reserve (FFR) is the current gold-standard invasive assessment of coronary artery disease (CAD). FFR reports coronary blood flow (CBF) as a fraction of a hypothetical and unknown normal value. Although used routinely to diagnose CAD and guide treatment, how accurately FFR predicts actual CBF changes remains unknown. Here we compared fractional CBF with the absolute CBF (aCBF in mL/min), measured with a computational method during standard angiography and pressure-wire assessment, on 203 diseased arteries (143 patients). We found a substantial correlation between the two measurements (r 0.89, Cohen's Kappa 0.71). Concordance between fractional and absolute CBF reduction was high when FFR was >0.80 (91%), but reduced when FFR was ≤0.80 (81%), 0.70-0.80 (68%) and, particularly 0.75-0.80 (62%). Discordance was associated with coronary microvascular resistance, vessel diameter and mass of myocardium subtended, all factors to which FFR is agnostic. Assessment of aCBF complements FFR, and may be valuable to assess CBF, particularly in cases within the FFR 'grey-zone'.
    Language English
    Publishing date 2022-07-04
    Publishing country England
    Document type Journal Article
    ISSN 2731-0590
    ISSN (online) 2731-0590
    DOI 10.1038/s44161-022-00091-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Virtual (Computed) Fractional Flow Reserve: Future Role in Acute Coronary Syndromes.

    Haley, Hazel Arfah / Ghobrial, Mina / Morris, Paul D / Gosling, Rebecca / Williams, Gareth / Mills, Mark T / Newman, Tom / Rammohan, Vignesh / Pederzani, Giulia / Lawford, Patricia V / Hose, Rodney / Gunn, Julian P

    Frontiers in cardiovascular medicine

    2021  Volume 8, Page(s) 735008

    Abstract: The current management of acute coronary syndromes (ACS) is with an invasive strategy to guide treatment. However, identifying the lesions which are physiologically significant can be challenging. Non-invasive imaging is generally not appropriate or ... ...

    Abstract The current management of acute coronary syndromes (ACS) is with an invasive strategy to guide treatment. However, identifying the lesions which are physiologically significant can be challenging. Non-invasive imaging is generally not appropriate or timely in the acute setting, so the decision is generally based upon visual assessment of the angiogram, supplemented in a small minority by invasive pressure wire studies using fractional flow reserve (FFR) or related indices. Whilst pressure wire usage is slowly increasing, it is not feasible in many vessels, patients and situations. Limited evidence for the use of FFR in non-ST elevation (NSTE) ACS suggests a 25% change in management, compared with traditional assessment, with a shift from more to less extensive revascularisation. Virtual (computed) FFR (vFFR), which uses a 3D model of the coronary arteries constructed from the invasive angiogram, and application of the physical laws of fluid flow, has the potential to be used more widely in this situation. It is less invasive, fast and can be integrated into catheter laboratory software. For severe lesions, or mild disease, it is probably not required, but it could improve the management of moderate disease in 'real time' for patients with non-ST elevation acute coronary syndromes (NSTE-ACS), and in bystander disease in ST elevation myocardial infarction. Its practicability and impact in the acute setting need to be tested, but the underpinning science and potential benefits for rapid and streamlined decision-making are enticing.
    Language English
    Publishing date 2021-10-22
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2781496-8
    ISSN 2297-055X
    ISSN 2297-055X
    DOI 10.3389/fcvm.2021.735008
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Study Design Features Associated with Patient Attrition in Studies of Traumatic Brain Injury: A Systematic Review.

    Richter, Sophie / Stevenson, Susan / Newman, Tom / Wilson, Lindsay / Maas, Andrew I R / Nieboer, Daan / Lingsma, Hester / Steyerberg, Ewout W / Newcombe, Virginia F J

    Journal of neurotrauma

    2020  Volume 37, Issue 17, Page(s) 1845–1853

    Abstract: Loss to follow-up or patient attrition is common in longitudinal studies of traumatic brain injury (TBI). Lack of understanding exists between the relation of study design and patient attrition. This review aimed to identify features of study design that ...

    Abstract Loss to follow-up or patient attrition is common in longitudinal studies of traumatic brain injury (TBI). Lack of understanding exists between the relation of study design and patient attrition. This review aimed to identify features of study design that are associated with attrition. We extended the analysis of a previous systematic review on missing data in 195 TBI studies using the Glasgow Outcome Scale Extended (GOSE) as an outcome measure. Studies that did not report attrition or had heterogeneous methodology were excluded, leaving 148 studies. Logistic regression found seven of the 14 design features studied to be associated with patient attrition. Four features were associated with an increase in attrition: greater follow-up frequency (odds ratio [OR]: 1.2, 95% confidence interval [CI]: 1.0-1.3), single rather than multi-center design (OR: 1.6, 95% CI: 1.2-2.2), enrollment of exclusively mild TBI patients (OR: 2.8, 95% CI: 1.6-4.9), and collection of the GOS by post or telephone without face-to-face contact (OR: 1.6, 95% CI:1.1-2.4). Conversely, two features were associated with a reduction in attrition: recruitment in an acute care setting defined as the ward or intensive care unit (OR: 0.58, 95% CI: 0.47-0.72) and a greater duration of time between injury and follow-up (OR: 0.93, 95% CI: 0.88-0.99). This review highlights design features that are associated with attrition and could be considered when planning for patient retention. Further work is needed to establish the mechanisms between the observed associations and potential remedies.
    MeSH term(s) Brain Injuries, Traumatic/epidemiology ; Brain Injuries, Traumatic/psychology ; Brain Injuries, Traumatic/therapy ; Glasgow Coma Scale/standards ; Glasgow Outcome Scale/standards ; Humans ; Longitudinal Studies ; Observational Studies as Topic/methods ; Outcome Assessment, Health Care/methods ; Outcome Assessment, Health Care/standards ; Patient Dropouts/psychology ; Patient Selection ; Research Design/standards
    Language English
    Publishing date 2020-05-14
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Systematic Review
    ZDB-ID 645092-1
    ISSN 1557-9042 ; 0897-7151
    ISSN (online) 1557-9042
    ISSN 0897-7151
    DOI 10.1089/neu.2020.7000
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Book ; Online: Self-supervised Skull Reconstruction in Brain CT Images with Decompressive Craniectomy

    Matzkin, Franco / Newcombe, Virginia / Stevenson, Susan / Khetani, Aneesh / Newman, Tom / Digby, Richard / Stevens, Andrew / Glocker, Ben / Ferrante, Enzo

    2020  

    Abstract: Decompressive craniectomy (DC) is a common surgical procedure consisting of the removal of a portion of the skull that is performed after incidents such as stroke, traumatic brain injury (TBI) or other events that could result in acute subdural ... ...

    Abstract Decompressive craniectomy (DC) is a common surgical procedure consisting of the removal of a portion of the skull that is performed after incidents such as stroke, traumatic brain injury (TBI) or other events that could result in acute subdural hemorrhage and/or increasing intracranial pressure. In these cases, CT scans are obtained to diagnose and assess injuries, or guide a certain therapy and intervention. We propose a deep learning based method to reconstruct the skull defect removed during DC performed after TBI from post-operative CT images. This reconstruction is useful in multiple scenarios, e.g. to support the creation of cranioplasty plates, accurate measurements of bone flap volume and total intracranial volume, important for studies that aim to relate later atrophy to patient outcome. We propose and compare alternative self-supervised methods where an encoder-decoder convolutional neural network (CNN) estimates the missing bone flap on post-operative CTs. The self-supervised learning strategy only requires images with complete skulls and avoids the need for annotated DC images. For evaluation, we employ real and simulated images with DC, comparing the results with other state-of-the-art approaches. The experiments show that the proposed model outperforms current manual methods, enabling reconstruction even in highly challenging cases where big skull defects have been removed during surgery.

    Comment: Accepted for publication in MICCAI 2020. Update: Figure 1 corrected to match description
    Keywords Electrical Engineering and Systems Science - Image and Video Processing ; Computer Science - Computer Vision and Pattern Recognition
    Subject code 006
    Publishing date 2020-07-07
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Handling of Missing Outcome Data in Traumatic Brain Injury Research: A Systematic Review.

    Richter, Sophie / Stevenson, Susan / Newman, Tom / Wilson, Lindsay / Menon, David K / Maas, Andrew I R / Nieboer, Daan / Lingsma, Hester / Steyerberg, Ewout W / Newcombe, Virginia F J

    Journal of neurotrauma

    2019  Volume 36, Issue 19, Page(s) 2743–2752

    Abstract: Traumatic brain injury (TBI) research commonly measures long-term functional outcome, but studies often suffer from missing data as patients are lost to follow-up. This review assesses the extent and handling of missing outcome data in the TBI literature ...

    Abstract Traumatic brain injury (TBI) research commonly measures long-term functional outcome, but studies often suffer from missing data as patients are lost to follow-up. This review assesses the extent and handling of missing outcome data in the TBI literature and provides a practical guide for future research. Relevant electronic databases were searched from January 1, 2012 to October 27, 2017 for TBI studies that used the Glasgow Outcome Scale or Glasgow Outcome Scale-Extended (GOS/GOSE) as an outcome measure. Studies were screened and data extracted in line with Cochrane guidance. A total of 195 studies, 21 interventional, 174 observational, with 104,688 patients were included. Using the reported follow-up rates in a mixed model, on average 91% of patients were predicted to return to follow-up at 6 months post-injury, 84% at 1 year, and 69% at 2 years. However, 36% of studies provided insufficient information to determine the number of subjects at each time-point. Of 139 studies that did report missing outcome data, only 50% attempted to identify why data were missing, with just 4 reporting their assumption on the "missingness mechanism." The handling of missing data was heterogeneous, with the most common method being its exclusion from analysis. These results confirm substantial variability in the standard of reporting and handling of missing outcome data in TBI research. We conclude that practical guidance is needed to facilitate meaningful and accurate study interpretation, and therefore propose a framework for the handling of missing outcome data in future TBI research.
    MeSH term(s) Brain Injuries, Traumatic ; Data Interpretation, Statistical ; Glasgow Outcome Scale ; Humans ; Research ; Research Design
    Keywords covid19
    Language English
    Publishing date 2019-06-17
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Systematic Review
    ZDB-ID 645092-1
    ISSN 1557-9042 ; 0897-7151
    ISSN (online) 1557-9042
    ISSN 0897-7151
    DOI 10.1089/neu.2018.6216
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Prevalence of hepatitis C among psychiatric patients in the public sector.

    Dinwiddie, Stephen H / Shicker, Louis / Newman, Tom

    The American journal of psychiatry

    2003  Volume 160, Issue 1, Page(s) 172–174

    Abstract: Objective: This study estimated the seroprevalence of hepatitis C virus in a public-sector psychiatric hospital.: Method: Patients admitted between Jan. 1, 1998, and Dec. 30, 2000, were routinely screened for hepatitis C virus antibody on admission.!# ...

    Abstract Objective: This study estimated the seroprevalence of hepatitis C virus in a public-sector psychiatric hospital.
    Method: Patients admitted between Jan. 1, 1998, and Dec. 30, 2000, were routinely screened for hepatitis C virus antibody on admission.
    Results: A total of 133 (8.5%) of 1,556 patients admitted were positive for the hepatitis C virus. Aminotransferase levels were elevated but rarely abnormal among patients positive for the hepatitis C virus. Hepatitis B surface antibody was found in 27.8% of the patients positive for the hepatitis C virus. These patients were more likely to receive a diagnosis of psychoactive substance use disorder but no other psychiatric diagnoses.
    Conclusions: The prevalence of hepatitis C virus is high among psychiatric patients in the public sector. Much needs to be learned about the role of universal screening and effective techniques for primary prevention and antiviral treatment in this population.
    MeSH term(s) Adult ; Comorbidity ; Female ; Hepatitis B/epidemiology ; Hepatitis C/epidemiology ; Hospitals, Psychiatric/statistics & numerical data ; Hospitals, Public/statistics & numerical data ; Humans ; Illinois/epidemiology ; Liver Function Tests ; Male ; Mass Screening/statistics & numerical data ; Mental Disorders/epidemiology ; Middle Aged ; Patient Admission/statistics & numerical data ; Retrospective Studies ; Seroepidemiologic Studies ; Substance Abuse, Intravenous/epidemiology
    Language English
    Publishing date 2003-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 280045-7
    ISSN 1535-7228 ; 0002-953X
    ISSN (online) 1535-7228
    ISSN 0002-953X
    DOI 10.1176/appi.ajp.160.1.172
    Database MEDical Literature Analysis and Retrieval System OnLINE

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