All Outputs (47)

Stochastic variational inference improves quantification of multiple timepoint arterial spin labelling perfusion MRI (2025)
Journal Article
Kirk, T. F., Kenyon, G. G., Craig, M. S., & Chappell, M. A. (2025). Stochastic variational inference improves quantification of multiple timepoint arterial spin labelling perfusion MRI. Frontiers in Neuroscience, 19, Article 1536752. https://doi.org/10.3389/fnins.2025.1536752

Multiple-timepoint arterial spin labelling MRI is a non-invasive imaging technique that permits measurement of both cerebral blood flow and arterial transit time, the latter of which is an emerging biomarker of interest for cerebrovascular health. Qu... Read More about Stochastic variational inference improves quantification of multiple timepoint arterial spin labelling perfusion MRI.

Arterial spin labelling perfusion MRI analysis for the Human Connectome Project Lifespan Ageing and Development studies (2025)
Journal Article
Kirk, T. F., McConnell, F. A. K., Toner, J., Craig, M. S., Carone, D., Li, X., Suzuki, Y., Coalson, T. S., Harms, M. P., Glasser, M. F., & Chappell, M. A. (2025). Arterial spin labelling perfusion MRI analysis for the Human Connectome Project Lifespan Ageing and Development studies. Imaging Neuroscience, https://doi.org/10.1162/imag_a_00444

The Human Connectome Project Lifespan studies cover the Development (5-21) and Aging (36-100+) phases of life. Arterial spin labelling (ASL) was included in the imaging protocol, resulting in one of the largest datasets collected to-date of high spat... Read More about Arterial spin labelling perfusion MRI analysis for the Human Connectome Project Lifespan Ageing and Development studies.

Regional changes in cerebral perfusion with age when accounting for changes in gray-matter volume (2024)
Journal Article
Hu, J., Craig, M. S., Knight, S. P., De Looze, C., Meaney, J. F., Kenney, R. A., Chen, X., & Chappell, M. A. (2024). Regional changes in cerebral perfusion with age when accounting for changes in gray-matter volume. Magnetic Resonance in Medicine, https://doi.org/10.1002/mrm.30376

Purpose
One possible contributing factor for cerebral blood flow (CBF) decline in normal aging is the increase in partial volume effects due to brain atrophy, as cortical thinning can exacerbate the contamination of gray-matter (GM) voxels by other... Read More about Regional changes in cerebral perfusion with age when accounting for changes in gray-matter volume.

Synthetic cerebral blood vessel generator for training anatomically plausible deep learning models (2024)
Presentation / Conference Contribution
Kenyon, G., Lau, S., Perperidis, A., CHAPPELL, M., & Jenkinson, M. (2024, July). Synthetic cerebral blood vessel generator for training anatomically plausible deep learning models. Presented at MIUA - Medical Image Understanding and Analysis - 2024, Manchester

Blood vessel networks, with their complex geometrical and topological characteristics, play a significant role in diagnosing and understanding various cerebrovascular diseases. Deep learning (DL) segmentation methods can aid in analysing these struct... Read More about Synthetic cerebral blood vessel generator for training anatomically plausible deep learning models.

Recommendations for quantitative cerebral perfusion MRI using multi‐timepoint arterial spin labeling: Acquisition, quantification, and clinical applications (2024)
Journal Article
Woods, J. G., Achten, E., Asllani, I., Bolar, D. S., Dai, W., Detre, J. A., Fan, A. P., Fernández‐Seara, M. A., Golay, X., Günther, M., Guo, J., Hernandez‐Garcia, L., Ho, M., Juttukonda, M. R., Lu, H., MacIntosh, B. J., Madhuranthakam, A. J., Mutsaerts, H., Okell, T. W., Parkes, L. M., …the ISMRM Perfusion Study Group. (2024). Recommendations for quantitative cerebral perfusion MRI using multi‐timepoint arterial spin labeling: Acquisition, quantification, and clinical applications. Magnetic Resonance in Medicine, 92(2), 469-495. https://doi.org/10.1002/mrm.30091

Accurate assessment of cerebral perfusion is vital for understanding the hemodynamic processes involved in various neurological disorders and guiding clinical decision-making. This guidelines article provides a comprehensive overview of quantitative... Read More about Recommendations for quantitative cerebral perfusion MRI using multi‐timepoint arterial spin labeling: Acquisition, quantification, and clinical applications.

Bayesian Inference for Non-linear forward model by using a VAE-based neural network structure (2024)
Journal Article
Zhang, Y., Zheng, J.-Q., & Chappell, M. (2024). Bayesian Inference for Non-linear forward model by using a VAE-based neural network structure. IEEE Transactions on Signal Processing, 72, 1400-1411. https://doi.org/10.1109/TSP.2024.3374115

In this paper, a Variational Autoencoder (VAE) based framework is introduced to solve parameter estimation problems for non-linear forward models. In particular, we focus on applications in the field of medical imaging where many thousands of model-b... Read More about Bayesian Inference for Non-linear forward model by using a VAE-based neural network structure.

BASIL: A Toolbox for Perfusion Quantification using Arterial Spin Labelling (2023)
Journal Article
Chappell, M. A., Kirk, T. F., Craig, M. S., McConnell, F. A. K., Zhao, M. Y., MacIntosh, B. J., Okell, T. W., & Woolrich, M. W. (2023). BASIL: A Toolbox for Perfusion Quantification using Arterial Spin Labelling. Imaging Neuroscience, https://doi.org/10.1162/imag_a_00041

Arterial Spin Labelling (ASL) MRI is now an established non-invasive method to quantify cerebral blood flow and is increasingly being used in a variety of neuroimaging applications. With standard ASL acquisition protocols widely available, there is a... Read More about BASIL: A Toolbox for Perfusion Quantification using Arterial Spin Labelling.

Unified Surface and Volumetric Inference on Functional Imaging Data (2023)
Presentation / Conference Contribution
Kirk, T. F., Craig, M. S., & Chappell, M. A. (2023, October). Unified Surface and Volumetric Inference on Functional Imaging Data. Presented at Medical Image Computing and Computer Assisted Intervention – MICCAI 2023, Vancouver, BC, Canada

Surface-based analysis methods for functional imaging data have been shown to offer substantial benefits for the study of the human cortex, namely in the localisation of functional areas and the establishment of inter-subject correspondence. A new ap... Read More about Unified Surface and Volumetric Inference on Functional Imaging Data.

Brain perfusion imaging by multi‐delay arterial spin labeling: Impact of modeling dispersion and interaction with denoising strategies and pathology (2023)
Journal Article
Pires Monteiro, S., Pinto, J., Chappell, M. A., Fouto, A., Baptista, M. V., Vilela, P., & Figueiredo, P. (2023). Brain perfusion imaging by multi‐delay arterial spin labeling: Impact of modeling dispersion and interaction with denoising strategies and pathology. Magnetic Resonance in Medicine, 90(5), 1889-1904. https://doi.org/10.1002/mrm.29783

Purpose: Arterial spin labeling (ASL) acquisitions at multiple post-labeling delays may provide more accurate quantification of cerebral blood flow (CBF), by fitting appropriate kinetic models and simultaneously estimating relevant parameters such as... Read More about Brain perfusion imaging by multi‐delay arterial spin labeling: Impact of modeling dispersion and interaction with denoising strategies and pathology.

MRI assessment of cerebral perfusion in clinical trials (2023)
Journal Article
Wang, X., Bishop, C., O'Callaghan, J., Gayhoor, A., Albani, J., Theriault, W., Chappell, M., Golay, X., Wang, D., & Becerra, L. (2023). MRI assessment of cerebral perfusion in clinical trials. Drug Discovery Today, 28(4), Article 103506. https://doi.org/10.1016/j.drudis.2023.103506

Neurodegenerative mechanisms affect the brain through a variety of processes that are reflected as changes in brain structure and physiology. Although some biomarkers for these changes are well established, others are at different stages of developme... Read More about MRI assessment of cerebral perfusion in clinical trials.

Time-encoded pseudo-continuous arterial spin labeling: Increasing SNR in ASL dynamic angiography (2022)
Journal Article
Woods, J. G., Schauman, S. S., Chiew, M., Chappell, M. A., & Okell, T. W. (2023). Time-encoded pseudo-continuous arterial spin labeling: Increasing SNR in ASL dynamic angiography. Magnetic Resonance in Medicine, 89(4), 1323-1341. https://doi.org/10.1002/mrm.29491

Purpose: Dynamic angiography using arterial spin labeling (ASL) can provide detailed hemodynamic information. However, the long time-resolved readouts require small flip angles to preserve ASL signal for later timepoints, limiting SNR. By using time-... Read More about Time-encoded pseudo-continuous arterial spin labeling: Increasing SNR in ASL dynamic angiography.

Potential Diagnostic Applications of Multi-Delay Arterial Spin Labeling in Early Alzheimer’s Disease: The Chinese Imaging, Biomarkers, and Lifestyle Study (2022)
Journal Article
Sun, M., Wang, Y. L., Li, R., Jiang, J., Zhang, Y., Li, W., Zhang, Y., Jia, Z., Chappell, M., & Xu, J. (2022). Potential Diagnostic Applications of Multi-Delay Arterial Spin Labeling in Early Alzheimer’s Disease: The Chinese Imaging, Biomarkers, and Lifestyle Study. Frontiers in Neuroscience, 16, Article 934471. https://doi.org/10.3389/fnins.2022.934471

Background: Cerebral blood flow (CBF) alterations are involved in the onset and progression of Alzheimer’s disease (AD) and can be a potential biomarker. However, CBF measured by single-delay arterial spin labeling (ASL) for discrimination of mild co... Read More about Potential Diagnostic Applications of Multi-Delay Arterial Spin Labeling in Early Alzheimer’s Disease: The Chinese Imaging, Biomarkers, and Lifestyle Study.

Review and consensus recommendations on clinical APT-weighted imaging approaches at 3T: Application to brain tumors (2022)
Journal Article
Zhou, J., Zaiss, M., Knutsson, L., Sun, P. Z., Ahn, S. S., Aime, S., Bachert, P., Blakeley, J. O., Cai, K., Chappell, M. A., Chen, M., Gochberg, D. F., Goerke, S., Heo, H. Y., Jiang, S., Jin, T., Kim, S., Laterra, J., Paech, D., Pagel, M. D., …Zijl, P. C. M. (2022). Review and consensus recommendations on clinical APT-weighted imaging approaches at 3T: Application to brain tumors. Magnetic Resonance in Medicine, 88(2), 546-574. https://doi.org/10.1002/mrm.29241

Amide proton transfer-weighted (APTw) MR imaging shows promise as a biomarker of brain tumor status. Currently used APTw MRI pulse sequences and protocols vary substantially among different institutes, and there are no agreed-on standards in the imag... Read More about Review and consensus recommendations on clinical APT-weighted imaging approaches at 3T: Application to brain tumors.

Amide proton transfer imaging in stroke (2022)
Journal Article
Heo, H. Y., Tee, Y. K., Harston, G., Leigh, R., & Chappell, M. A. (2022). Amide proton transfer imaging in stroke. NMR in Biomedicine, Article e4734. https://doi.org/10.1002/nbm.4734

Amide proton transfer (APT) imaging, a variant of chemical exchange saturation transfer MRI, has shown promise in detecting ischemic tissue acidosis following impaired aerobic metabolism in animal models and in human stroke patients due to the sensit... Read More about Amide proton transfer imaging in stroke.

Quantitative chemical exchange saturation transfer imaging of nuclear overhauser effects in acute ischemic stroke (2022)
Journal Article
Msayib, Y., Harston, G. W., Ray, K. J., Larkin, J. R., Sutherland, B. A., Sheerin, F., Blockley, N. P., Okell, T. W., Jezzard, P., Baldwin, A., Sibson, N. R., Kennedy, J., & Chappell, M. A. (2022). Quantitative chemical exchange saturation transfer imaging of nuclear overhauser effects in acute ischemic stroke. Magnetic Resonance in Medicine, 88(1), 341-356. https://doi.org/10.1002/mrm.29187

Purpose: In chemical exchange saturation transfer imaging, saturation effects between (Formula presented.) 2 to (Formula presented.) 5 ppm (nuclear Overhauser effects, NOEs) have been shown to exhibit contrast in preclinical stroke models. Our previo... Read More about Quantitative chemical exchange saturation transfer imaging of nuclear overhauser effects in acute ischemic stroke.

Validation of the estimation of the macrovascular contribution in multi‐timepoint arterial spin labeling MRI using a 2‐component kinetic model (2021)
Journal Article
Plas, M. C. E., Craig, M., Schmid, S., Chappell, M. A., & Osch, M. J. P. (2022). Validation of the estimation of the macrovascular contribution in multi‐timepoint arterial spin labeling MRI using a 2‐component kinetic model. Magnetic Resonance in Medicine, 87(1), 85-101. https://doi.org/10.1002/mrm.28960

Purpose
In this paper, the ability to quantify cerebral blood flow by arterial spin labeling (ASL) was studied by investigating the separation of the macrovascular and tissue component using a 2-component model. Underlying assumptions of this model,... Read More about Validation of the estimation of the macrovascular contribution in multi‐timepoint arterial spin labeling MRI using a 2‐component kinetic model.

Partial volume correction in arterial spin labeling perfusion MRI: A method to disentangle anatomy from physiology or an analysis step too far? (2021)
Journal Article
Chappell, M. A., McConnell, F. A. K., Golay, X., Günther, M., Hernandez-Tamames, J. A., van Osch, M. J., & Asllani, I. (2021). Partial volume correction in arterial spin labeling perfusion MRI: A method to disentangle anatomy from physiology or an analysis step too far?. NeuroImage, 238, Article 118236. https://doi.org/10.1016/j.neuroimage.2021.118236

The mismatch in the spatial resolution of Arterial Spin Labeling (ASL) MRI perfusion images and the anatomy of functionally distinct tissues in the brain leads to a partial volume effect (PVE), which in turn confounds the estimation of perfusion into... Read More about Partial volume correction in arterial spin labeling perfusion MRI: A method to disentangle anatomy from physiology or an analysis step too far?.

Examination of optimized protocols for pCASL: Sensitivity to macrovascular contamination, flow dispersion, and prolonged arterial transit time (2021)
Journal Article
Zhang, L. X., Woods, J. G., Okell, T. W., & Chappell, M. A. (2021). Examination of optimized protocols for pCASL: Sensitivity to macrovascular contamination, flow dispersion, and prolonged arterial transit time. Magnetic Resonance in Medicine, 86(4), 2208-2219. https://doi.org/10.1002/mrm.28839

Purpose
Previously, multi- post-labeling delays (PLD) pseudo-continuous arterial spin labeling (pCASL) protocols have been optimized for the estimation accuracy of the cerebral blood flow (CBF) with/without the arterial transit time (ATT) under a st... Read More about Examination of optimized protocols for pCASL: Sensitivity to macrovascular contamination, flow dispersion, and prolonged arterial transit time.

Obesity is associated with reduced cerebral blood flow – modified by physical activity (2021)
Journal Article
Knight, S. P., Laird, E., Williamson, W., O'Connor, J., Newman, L., Carey, D., De Looze, C., Fagan, A. J., Chappell, M. A., Meaney, J. F., & Kenny, R. A. (2021). Obesity is associated with reduced cerebral blood flow – modified by physical activity. Neurobiology of Aging, 105, 35-47. https://doi.org/10.1016/j.neurobiolaging.2021.04.008

This study examined the associations of body mass index (BMI), waist-to-hip ratio (WHR), waist circumference (WC), and physical activity (PA) with gray matter cerebral blood flow (CBFGM) in older adults. Cross-sectional data was used from the Irish L... Read More about Obesity is associated with reduced cerebral blood flow – modified by physical activity.

Study Protocol: The Heart and Brain Study (2021)
Journal Article
Suri, S., Bulte, D., Chiesa, S. T., Ebmeier, K. P., Jezzard, P., Rieger, S. W., Pitt, J. E., Griffanti, L., Okell, T. W., Craig, M., Chappell, M. A., Blockley, N. P., Kivimäki, M., Singh-Manoux, A., Khir, A. W., Hughes, A. D., Deanfield, J. E., Jensen, D. E. A., Green, S. F., Sigutova, V., …Mackay, C. E. (2021). Study Protocol: The Heart and Brain Study. Frontiers in Physiology, 12, Article 643725. https://doi.org/10.3389/fphys.2021.643725

Background: It is well-established that what is good for the heart is good for the brain. Vascular factors such as hypertension, diabetes, and high cholesterol, and genetic factors such as the apolipoprotein E4 allele increase the risk of developing... Read More about Study Protocol: The Heart and Brain Study.