Helen Dawes

Dr. Helen Dawes

College of Medicine and Health, St. Luke’s Campus, University of Exeter, Exeter EX1 2LU, UK
orcid

Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2017 in The Lancet Neurology
Verified
Journal Article
Closed access
AMAndrew I R Maas
Andrew I R Maas
DMDavid K Menon
David K Menon
PAP David Adelson
P David Adelson
NANada Andelic
Nada Andelic
MBMichael J Bell
Michael J Bell
FZFabrizio Zumbo
Fabrizio Zumbo

1 January 2011 in Neuroscience & Biobehavioral Reviews
Verified
Journal Article
Closed access
EAEmad Al-Yahya
Emad Al-Yahya
HDHelen Dawes
Helen Dawes
LSLesley Smith
Lesley Smith
ADAndrea Dennis
Andrea Dennis
KHKen Howells
Ken Howells
JCJanet Cockburn
Janet Cockburn

1 October 2019 in The Lancet Neurology
Verified
Journal Article
Open access
ESEwout W Steyerberg
Ewout W Steyerberg
EWEveline Wiegers
Eveline Wiegers
CSCharlie Sewalt
Charlie Sewalt
ABAndras Buki
Andras Buki
GCGiuseppe Citerio
Giuseppe Citerio
TZTommaso Zoerle
Tommaso Zoerle
The burden of traumatic brain injury (TBI) poses a large public health and societal problem, but the characteristics of patients and their care pathways in Europe are poorly understood. We aimed to characterise patient case-mix, care pathways, and outcomes of TBI. CENTER-TBI is a Europe-based, observational cohort study, consisting of a core study and a registry. Inclusion criteria for the core study were a clinical diagnosis of TBI, presentation fewer than 24 h after injury, and an indication for CT. Patients were differentiated by care pathway and assigned to the emergency room (ER) stratum (patients who were discharged from an emergency room), admission stratum (patients who were admitted to a hospital ward), or intensive care unit (ICU) stratum (patients who were admitted to the ICU). Neuroimages and biospecimens were stored in repositories and outcome was assessed at 6 months after injury. We used the IMPACT core model for estimating the expected mortality and proportion with unfavourable Glasgow Outcome Scale Extended (GOSE) outcomes in patients with moderate or severe TBI (Glasgow Coma Scale [GCS] score ≤12). The core study was registered with ClinicalTrials.gov, number NCT02210221, and with Resource Identification Portal (RRID: SCR_015582). Data from 4509 patients from 18 countries, collected between Dec 9, 2014, and Dec 17, 2017, were analysed in the core study and from 22 782 patients in the registry. In the core study, 848 (19%) patients were in the ER stratum, 1523 (34%) in the admission stratum, and 2138 (47%) in the ICU stratum. In the ICU stratum, 720 (36%) patients had mild TBI (GCS score 13-15). Compared with the core cohort, the registry had a higher proportion of patients in the ER (9839 [43%]) and admission (8571 [38%]) strata, with more than 95% of patients classified as having mild TBI. Patients in the core study were older than those in previous studies (median age 50 years [IQR 30-66], 1254 [28%] aged >65 years), 462 (11%) had serious comorbidities, 772 (18%) were taking anticoagulant or antiplatelet medication, and alcohol was contributory in 1054 (25%) TBIs. MRI and blood biomarker measurement enhanced characterisation of injury severity and type. Substantial inter-country differences existed in care pathways and practice. Incomplete recovery at 6 months (GOSE <8) was found in 207 (30%) patients in the ER stratum, 665 (53%) in the admission stratum, and 1547 (84%) in the ICU stratum. Among patients with moderate-to-severe TBI in the ICU stratum, 623 (55%) patients had unfavourable outcome at 6 months (GOSE <5), similar to the proportion predicted by the IMPACT prognostic model (observed to expected ratio 1·06 [95% CI 0·97-1·14]), but mortality was lower than expected (0·70 [0·62-0·76]). Patients with TBI who presented to European centres in the core study were older than were those in previous observational studies and often had comorbidities. Overall, most patients presented with mild TBI. The incomplete recovery of many patients should motivate precision medicine research and the identification of best practices to improve these outcomes. European Union 7th Framework Programme, the Hannelore Kohl Stiftung, OneMind, and Integra LifeSciences Corporation.

1 December 2002 in Brain
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Journal Article
Open access
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HJHeidi Johansen‐Berg
Heidi Johansen‐Berg
HDHelen Dawes
Helen Dawes
CGClaire Guy
Claire Guy
SSStephen M. Smith
Stephen M. Smith
DWDerick T. Wade
Derick T. Wade
PMPaul M. Matthews
Paul M. Matthews
Motor rehabilitation therapy is commonly employed after strokes, but outcomes are variable and there is little specific information about the changes in brain activity that are associated with improved function. We performed serial functional MRI (fMRI) on a group of seven patients receiving a form of rehabilitation therapy after stroke in order to characterize functional changes in the brain that correlate with behavioural improvements. Patients were scanned while performing a hand flexion–extension movement twice before and twice after a two‐week home‐based therapy programme combining restraint of the unaffected limb with progressive exercises for the affected limb. As expected, the extent of improvement in hand function after therapy varied between patients. Therapy‐related improvements in hand function correlated with increases in fMRI activity in the premotor cortex and secondary somatosensory cortex contralateral to the affected hand, and in superior posterior regions of the cerebellar hemispheres bilaterally (Crus I and lobule VI). fMRI offers a promising, objective approach for specifically identifying changes in brain activity potentially responsible for rehabilitation‐mediated recovery of function after stroke. Our results suggest that activity changes in sensorimotor regions are associated with successful motor rehabilitation.

10 September 2018 in Nature Biotechnology
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Journal Article
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OSOmid G Sani
Omid G Sani
YYYuxiao Yang
Yuxiao Yang
MLMorgan B Lee
Morgan B Lee
HDHelen Dawes
Helen Dawes
ECEdward F Chang
Edward F Chang
MSMaryam M Shanechi
Maryam M Shanechi

1 May 2016 in NeuroImage
Verified
Journal Article
Open access
CSClaire E. Sexton
Claire E. Sexton
JBJill F. Betts
Jill F. Betts
NDNaiara Demnitz
Naiara Demnitz
HDHelen Dawes
Helen Dawes
KEKlaus P. Ebmeier
Klaus P. Ebmeier
HJHeidi Johansen-Berg
Heidi Johansen-Berg
Higher levels of physical fitness or activity (PFA) have been shown to have beneficial effects on cognitive function and grey matter volumes in older adults. However, the relationship between PFA and the brain's white matter (WM) is not yet well established. Here, we aim to provide a comprehensive and systematic review of magnetic resonance imaging studies examining the effects of PFA on the WM of the ageing brain. Twenty-nine studies were included in the review: eleven examined WM volume, fourteen WM lesions, and nine WM microstructure. While many studies found that higher levels of PFA were associated with greater WM volumes, reduced volume or severity of WM lesions, or improved measures of WM microstructure, a number of negative findings have also been published. Meta-analyses of global measures of WM volume and WM lesion volume yielded significant, but small, effect sizes. Overall, we found evidence for cautious support of links between PFA and WM structure, and highlighted key areas for future research including the extent to which the relationship between PFA and WM structure is anatomically specific, the influence of possible confounding factors, and the relationship between PFA, WM and cognition.