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20242026
most citedLikelihood-Scheduled Score-Based Generative Modeling for Fully 3D PET Image Reconstruction

7 citations · 9 across the 12 of their papers we have counts for

collaborators

13 papers

cs.CV2026

Discovery and Spatial Characterisation of Multiple Shortcut Groups for Auditing Vision Model Bias

Akshit Achara, Vishnunarayan Manickam, Thomas Day +3

Deep learning models trained on datasets with spurious correlations can achieve high average accuracy whilst relying on shortcut features that do not generalise out of distribution…

cs.CV2026

Learning Cardiac Motion Priors for Implicit Neural Representations

Andrew Bell, George Webber, Steffen E Petersen +3

Implicit neural representations (INRs) are well suited to cardiac motion estimation, providing continuous, compact representations of motion fields. However, fitting an INR to each…

cs.CV2026

Right Regions, Wrong Labels: Semantic Label Flips in Segmentation under Correlation Shift

Akshit Achara, Yovin Yahathugoda, Nick Byrne +4

The robustness of machine learning models can be compromised by spurious correlations between non-causal features in the input data and target labels. A common way to test for such…

cs.CV2025

Localising Shortcut Learning in Pixel Space via Ordinal Scoring Correlations for Attribution Representations (OSCAR)

Akshit Achara, Peter Triantafillou, Esther Puyol-Antón +2

Deep neural networks often exploit shortcuts. These are spurious cues which are associated with output labels in the training data but are unrelated to task semantics. When the sho…

physics.med-ph2025

Steerable Conditional Diffusion for Domain Adaptation in PET Image Reconstruction

George Webber, Alexander Hammers, Andrew P. King +1

Diffusion models have recently enabled state-of-the-art reconstruction of positron emission tomography (PET) images while requiring only image training data. However, domain shift…

cs.CV2025

Invisible Attributes, Visible Biases: Exploring Demographic Shortcuts in MRI-based Alzheimer's Disease Classification

Akshit Achara, Esther Puyol Anton, Alexander Hammers +1

Magnetic resonance imaging (MRI) is the gold standard for brain imaging. Deep learning (DL) algorithms have been proposed to aid in the diagnosis of diseases such as Alzheimer's di…

cs.CY2025

Themed Challenges to Solve Data Scarcity in Africa: A Proposition for Increasing Local Data Collection and Integration

Mubaraq Yakubu, Udunna Anazodo, Maruf Adewole +6

In Africa, the scarcity of computational resources and medical datasets remains a major hurdle to the development and deployment of artificial intelligence (AI) tools in clinical s…

physics.med-ph2025

Supervised Diffusion-Model-Based PET Image Reconstruction

George Webber, Alexander Hammers, Andrew P King +1

Diffusion models (DMs) have recently been introduced as a regularizing prior for PET image reconstruction, integrating DMs trained on high-quality PET images with unsupervised sche…

eess.IV2025

Systematic Review of Pituitary Gland and Pituitary Adenoma Automatic Segmentation Techniques in Magnetic Resonance Imaging

Mubaraq Yakubu, Navodini Wijethilake, Jonathan Shapey +2

Purpose: Accurate segmentation of both the pituitary gland and adenomas from magnetic resonance imaging (MRI) is essential for diagnosis and treatment of pituitary adenomas. This s…

physics.med-ph2025★ 1 cited

Personalized MR-Informed Diffusion Models for 3D PET Image Reconstruction

George Webber, Alexander Hammers, Andrew P. King +1

Recent work has shown improved lesion detectability and flexibility to reconstruction hyperparameters (e.g. scanner geometry or dose level) when PET images are reconstructed by lev…

physics.med-ph2024

Multi-Subject Image Synthesis as a Generative Prior for Single-Subject PET Image Reconstruction

George Webber, Yuya Mizuno, Oliver D. Howes +3

Large high-quality medical image datasets are difficult to acquire but necessary for many deep learning applications. For positron emission tomography (PET), reconstructed image qu…

physics.med-ph2024★ 1 cited

Generative-Model-Based Fully 3D PET Image Reconstruction by Conditional Diffusion Sampling

George Webber, Yuya Mizuno, Oliver D. Howes +3

Score-based generative models (SGMs) have recently shown promising results for image reconstruction on simulated positron emission tomography (PET) datasets. In this work we have d…

physics.med-ph2024★ 7 cited

Likelihood-Scheduled Score-Based Generative Modeling for Fully 3D PET Image Reconstruction

George Webber, Yuya Mizuno, Oliver D. Howes +3

Medical image reconstruction with pre-trained score-based generative models (SGMs) has advantages over other existing state-of-the-art deep-learned reconstruction methods, includin…