Publications by authors named "Mark Jenkinson"

Although primarily characterised as a motor disorder, Parkinson's Disease (PD) also presents with non-motor symptoms, including cognitive decline and affective dysfunction, which are major predictors of quality of life and mortality for individuals. However, factors associated with these non-motor symptom trajectories remain under-characterised. This study aimed to investigate predictors of cognitive and affective function over a 5-year follow-up period using data from the Progressive Parkinson's Marker Initiative.

View Article and Find Full Text PDF

Aims: Hip preservation surgeons are increasingly using commercially available 3D motion analysis software to investigate areas of impingement and quantify femoral head coverage. Variations in functional pelvic tilt will affect the position of the acetabular rim and projected femoral head coverage, but currently the majority of available software standardizes sagittal rotation to the anterior pelvic plane (APP). The study hypothesis was that the APP does not correlate well with patient-specific pelvic position.

View Article and Find Full Text PDF

Aims: A range of metal-on-metal hip resurfacing (MoM-HR) implants have shown good functional outcomes, but some have been associated with adverse reactions to metal debris (ARMD) and early failure, requiring regular follow-up and monitoring of the blood metal ion levels. The aim of this study was to report the minimum 15-year survival of the Durom hip resurfacing system (Zimmer Biomet, USA), the functional outcome, and factors which were predictive of failure.

Methods: A consecutive series of patients undergoing Durom MoM-HR at a single centre between January 2000 and December 2008 were included.

View Article and Find Full Text PDF

Deformable brain templates are an important tool in many neuroimaging analyses. Conditional templates (e.g.

View Article and Find Full Text PDF

Despite its great potential for studying the living brain, magnetic resonance imaging (MRI) can be often limited by nuisance non-biological factors, such as hardware/software differences between scanners, which can interfere with biological variability. This lack of standardisation or harmonisation between scanners hinders reproducibility and quantifiability of MRI. Towards addressing this challenge, we present one of the most comprehensive MRI harmonisation resources, based on a travelling heads paradigm; healthy volunteers scanned repeatedly across different scanners.

View Article and Find Full Text PDF

Given the relationship between hippocampal atrophy and cognitive impairment in various pathological conditions, hippocampus segmentation from MRI is an important task in neuroimaging. Manual segmentation, though considered the gold standard, is time-consuming and error-prone, leading to the development of numerous automatic segmentation methods. However, no study has yet independently compared the performance of traditional, deep learning-based and hippocampal subfield segmentation methods within a single investigation.

View Article and Find Full Text PDF

Cerebral microbleeds (CMBs) are small, hypointense hemosiderin deposits in the brain measuring 2-10 mm in diameter. As one of the important biomarkers of small vessel disease, they have been associated with various neurodegenerative and cerebrovascular diseases. Hence, automated detection, and subsequent extraction of clinically useful metrics (e.

View Article and Find Full Text PDF
Article Synopsis
  • The paper focuses on optimizing machine learning for image segmentation using small datasets, specifically for medical physicists to improve hyperparameter selection.
  • It details a case study utilizing a public CT dataset with 658 models trained, noting the process involved a grid search to identify effective hyperparameters and metrics.
  • Results showed that while overall accuracy and precision were high, the importance of specific hyperparameters varied, suggesting the proposed method enhances understanding and improves model validity despite existing data limitations.
View Article and Find Full Text PDF

Neuroimaging involves the acquisition of extensive 3D images and 4D time series data to gain insights into brain structure and function. The analysis of such data necessitates both spatial and temporal processing. In this context, "fslmaths" has established itself as a foundational software tool within our field, facilitating domain-specific image processing.

View Article and Find Full Text PDF

Studies exploring the brain correlates of behavioral symptoms in the frontotemporal dementia spectrum (FTD) have mainly searched for linear correlations with single modality neuroimaging data, either structural magnetic resonance imaging (MRI) or fluoro-deoxy-D-glucose positron emission tomography (FDG-PET). We aimed at studying the two imaging modalities in combination to identify nonlinear co-occurring patterns of atrophy and hypometabolism related to behavioral symptoms. We analyzed data from 93 FTD patients who underwent T1-weighted MRI, FDG-PET imaging, and neuropsychological assessment including the Neuropsychiatric Inventory, Frontal Systems Behavior Scale, and Neurobehavioral Rating Scale.

View Article and Find Full Text PDF

Since the rise of deep learning, new medical segmentation methods have rapidly been proposed with extremely promising results, often reporting marginal improvements on the previous state-of-the-art (SOTA) method. However, on visual inspection errors are often revealed, such as topological mistakes (e.g.

View Article and Find Full Text PDF

Background: Accurate outcome predictions for patients who had ischaemic stroke with successful reperfusion after endovascular thrombectomy (EVT) may improve patient treatment and care. Our study developed prediction models for key clinical outcomes in patients with successful reperfusion following EVT in an Australian population.

Methods: The study included all patients who had ischaemic stroke with occlusion in the proximal anterior cerebral circulation and successful reperfusion post-EVT over a 7-year period.

View Article and Find Full Text PDF
Article Synopsis
  • Spinal cord pathology significantly contributes to disability in progressive multiple sclerosis, with demyelinated lesions being a key feature tying directly to patient outcomes.
  • A study of 119 confirmed MS cases revealed that 76.5% had at least one spinal cord lesion, predominantly affecting the cervical region and showing high levels of inflammation.
  • The research suggests that lesion patterns are influenced by the vascular network within the spinal cord, indicating that blood-related factors may play a central role in lesion development and progression of the disease.
View Article and Find Full Text PDF

Aims: Elevated blood cobalt levels secondary to metal-on-metal (MoM) hip arthroplasties are a suggested risk factor for developing cardiovascular complications including cardiomyopathy. Clinical studies assessing patients with MoM hips using left ventricular ejection fraction (LVEF) have found conflicting evidence of cobalt-induced cardiomyopathy. Global longitudinal strain (GLS) is an echocardiography measurement known to be more sensitive than LVEF when diagnosing early cardiomyopathies.

View Article and Find Full Text PDF

Aims: The aim of this study is to evaluate whether acetabular retroversion (AR) represents a structural anatomical abnormality of the pelvis or is a functional phenomenon of pelvic positioning in the sagittal plane, and to what extent the changes that result from patient-specific functional position affect the extent of AR.

Methods: A comparative radiological study of 19 patients (38 hips) with AR were compared with a control group of 30 asymptomatic patients (60 hips). CT scans were corrected for rotation in the axial and coronal planes, and the sagittal plane was then aligned to the anterior pelvic plane.

View Article and Find Full Text PDF

Huntington's and Parkinson's disease are two movement disorders representing mainly opposite states of the basal ganglia inhibitory function. Despite being an integral part of the cortico-subcortico-cortical circuitry, the subthalamic nucleus function has been studied at the level of detail required to isolate its signal only through invasive studies in Huntington's and Parkinson's disease. Here, we tested whether the subthalamic nucleus exhibited opposite functional signatures in early Huntington's and Parkinson's disease.

View Article and Find Full Text PDF

Despite the huge potential of magnetic resonance imaging (MRI) in mapping and exploring the brain, MRI measures can often be limited in their consistency, reproducibility, and accuracy which subsequently restricts their quantifiability. Nuisance nonbiological factors, such as hardware, software, calibration differences between scanners, and post-processing options, can contribute to, or drive trends in, neuroimaging features to an extent that interferes with biological variability. Such lack of consistency, known as lack of harmonisation, across neuroimaging datasets poses a great challenge for our capabilities in quantitative MRI.

View Article and Find Full Text PDF
Article Synopsis
  • The study presents a digital atlas of fetal brain maturation based on data from healthy pregnancies, ensuring accurate dating and growth tracking of fetuses from early pregnancy to age two.
  • The atlas, created using 1,059 high-quality 3D ultrasound images, offers detailed structural insights into brain development, particularly in deep grey matter, which aligns well with existing MRI studies.
  • It highlights the emergence of asymmetries related to language and brain function as early as 14 weeks of gestation, establishing a valuable reference for understanding normative fetal brain growth and neurodevelopment.
View Article and Find Full Text PDF

Background: Studies exploring the brain correlates of behavioural symptoms in the frontotemporal dementia spectrum (FTD) have mainly searched for linear correlations with single modality neuroimaging data, either structural magnetic resonance imaging (MRI) or fluoro-deoxy-D-glucose positron emission tomography (FDG-PET). We aimed at studying the two imaging modalities in combination to identify nonlinear co-occurring patterns of atrophy and hypometabolism related to behavioural symptoms.

Methods: We analysed data from 93 FTD patients who underwent T1-weighted MRI, FDG-PET imaging, and neuropsychological assessment including the Neuropsychiatric Inventory, Frontal Systems Behaviour Scale, and Neurobehavioral Rating Scale.

View Article and Find Full Text PDF

In this work we present BIANCA-MS, a novel tool for brain white matter lesion segmentation in multiple sclerosis (MS), able to generalize across both the wide spectrum of MRI acquisition protocols and the heterogeneity of manually labeled data. BIANCA-MS is based on the original version of BIANCA and implements two innovative elements: a harmonized setting, tested under different MRI protocols, which avoids the need to further tune algorithm parameters to each dataset; and a cleaning step developed to improve consistency in automated and manual segmentations, thus reducing unwanted variability in output segmentations and validation data. BIANCA-MS was tested on three datasets, acquired with different MRI protocols.

View Article and Find Full Text PDF
Article Synopsis
  • Cerebral microbleeds (CMBs) are small brain lesions linked to various diseases and are visualized differently on certain imaging methods, prompting the need for accurate detection to derive imaging biomarkers.
  • This study introduces a fully automated, three-step deep learning algorithm that detects CMBs using different imaging modalities, improving detection sensitivity and reducing false positives.
  • Results showed that the algorithm achieved over 90% true positive rate in detecting CMBs within datasets, significantly enhancing detection accuracy compared to existing methods, and demonstrated good generalizability across varied datasets.
View Article and Find Full Text PDF

Objectives: Physical exercise therapy is effective for some people with chronic nonspecific neck pain but not for others. Differences in exercise-induced pain-modulatory responses are likely driven by brain changes. We investigated structural brain differences at baseline and changes after an exercise intervention.

View Article and Find Full Text PDF

It is commonly asserted that MRI-derived lesion masks outperform CT-derived lesion masks in lesion-mapping analysis. However, no quantitative analysis has been conducted to support or refute this claim. This study reports an objective comparison of lesion-mapping analyses based on CT- and MRI-derived lesion masks to clarify how input imaging type may ultimately impact analysis results.

View Article and Find Full Text PDF

Modelling population reference curves or normative modelling is increasingly used with the advent of large neuroimaging studies. In this paper we assess the performance of fitting methods from the perspective of clinical applications and investigate the influence of the sample size. Further, we evaluate linear and non-linear models for percentile curve estimation and highlight how the bias-variance trade-off manifests in typical neuroimaging data.

View Article and Find Full Text PDF

Background: Accurate registration between microscopy and MRI data is necessary for validating imaging biomarkers against neuropathology, and to disentangle complex signal dependencies in microstructural MRI. Existing registration methods often rely on serial histological sampling or significant manual input, providing limited scope to work with a large number of stand-alone histology sections. Here we present a customisable pipeline to assist the registration of stand-alone histology sections to whole-brain MRI data.

View Article and Find Full Text PDF