Causal Generative AI

The power of
causal generative AI

Harness the power of causal generative AI for super-realistic image synthesis—transforming how you develop, test, and validate AI.

Our technology enables high-fidelity data augmentation to boost performance, stress testing to uncover hidden vulnerabilities, and bias detection to ensure fair and equitable predictions across diverse populations.

For faster, safer, and better innovation in imaging AI.

Abstract visualisation of causal generative AI synthesising medical imaging data

Turbo charge AI with
super-realistic image synthesis

Illustration representing data augmentation with a rocket launch

Data augmentation

Enhance your training datasets with clinically valid, diverse, and accurate synthetic scans. Our causal generative AI creates high-fidelity medical images that preserve causal relationships—boosting model performance and robustness.

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Stress testing

Simulate edge cases, imaging artefacts, and underrepresented patient profiles to rigorously test your AI model's reliability. Our platform helps uncover hidden failure modes before deployment, supporting safer and more trustworthy clinical AI.

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Bias mitigation

Expose and quantify performance disparities across demographic subgroups using controlled, diverse synthetic data. Our technology enables fairness audits and bias mitigation strategies, aligning your AI with regulatory and ethical standards.

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Our approach

The science
behind the tech

Our technology is based on rigorous science, theoretical analyses, and extensive experimentation, resulting in the most advanced methodology for targeted super-realistic image synthesis, combining causal modelling with the power of deep generative AI.

With a click of a button, we simulate ‘what-if’ scenarios: What would this patient's scan look like if there were no disease? What would the image characteristics be if a different scanner were used?

This is what we call Imaginable Imaging.

Peer-reviewed

Research &
Publications

Our work is peer-reviewed and published in the leading AI conferences and journals such as NeurIPS, ICML, ICLR, and Nature Machine Intelligence. Our technology is rooted in rigorous science, theoretical analyses, and extensive experimentation.

Check out some of our selected papers.

Illustration representing AI research papers and publications

CF-Seg: Counterfactuals meet Segmentation

Raghav Mehta, Fabio De Sousa Ribeiro, Tian Xia, Mélanie Roschewitz, Ainkaran Santhirasekaram, Dominic C. Marshall, Ben Glocker

MICCAI, 2025

CF-Seg is a framework that enhances anatomical segmentation in medical images by generating pseudo-healthy counterfactuals. Using deep structural causal models, it improves segmentation accuracy without modifying existing models. Evaluations on chest X-ray datasets show CF-Seg outperforms standard methods, especially in cases with pleural effusion, and is preferred by radiologists.

Diffusion Counterfactual Generation with Semantic Abduction

Rajat Rasal, Avinash Kori, Fabio De Sousa Ribeiro, Tian Xia, Ben Glocker

ICML, 2025

This paper introduces diffusion-based causal mechanisms for generating high-fidelity image counterfactuals. By integrating semantic abduction and dynamic guidance into diffusion models, the framework balances identity preservation and causal faithfulness. It outperforms prior methods across tasks like face editing and medical artefact removal, advancing counterfactual reasoning in complex visual domains.

Robust image representations with counterfactual contrastive learning

Mélanie Roschewitz, Fabio De Sousa Ribeiro, Tian Xia, Galvin Khara, Ben Glocker

Medical Image Analysis, 2025

Counterfactual contrastive learning enhances robustness in medical image representation by generating realistic domain-shifted image pairs using causal generative models. Evaluated on chest X-rays and mammograms, it outperforms standard contrastive methods across diverse scanners and label regimes, improving generalization, especially for underrepresented domains and subgroups, using both SimCLR and DINO-v2 frameworks.

Mitigating attribute amplification in counterfactual image generation

Tian Xia, Mélanie Roschewitz, Fabio De Sousa Ribeiro, Charles Jones, Ben Glocker

MICCAI, 2024

This paper identifies "attribute amplification" in counterfactual image generation, where unintended features change during interventions. We propose Soft Counterfactual Fine-Tuning (Soft-CFT), which uses soft labels to preserve non-intervened attributes. Experiments on chest X-rays show Soft-CFT improves faithfulness and reduces bias, enhancing reliability in medical imaging applications.

A causal perspective on dataset bias in machine learning for medical imaging

Charles Jones, Daniel C. Castro, Fabio De Sousa Ribeiro, Ozan Oktay, Melissa McCradden, Ben Glocker

Nature Machine Intelligence, 2024

This paper presents a causal framework for understanding dataset bias in medical imaging. It identifies three bias types—prevalence, presentation, and annotation disparities—and shows how each requires distinct mitigation strategies. We propose a three-step fairness reasoning process and emphasize the need for explicit causal assumptions and transparency in model development and evaluation.

Measuring axiomatic soundness of counterfactual image models

Miguel Monteiro, Fabio De Sousa Ribeiro, Nick Pawlowski, Daniel C. Castro, Ben Glocker

ICLR, 2023

This paper proposes a framework to evaluate counterfactual image models using axiomatic principles—composition, reversibility, and effectiveness—without needing ground-truth counterfactuals. It introduces metrics to assess model soundness, explores simulated interventions to mitigate confounding, and compares generative models across datasets, highlighting trade-offs in counterfactual fidelity and interpretability.

High fidelity image counterfactuals with probabilistic causal models

Fabio De Sousa Ribeiro, Tian Xia, Miguel Monteiro, Nick Pawlowski, Ben Glocker

ICML, 2023

This paper introduces a deep causal generative framework for producing high-fidelity image counterfactuals. By combining hierarchical variational autoencoders with structural causal models, it enables estimation of direct, indirect, and total effects. The use of synthetic images could improve explainability, robustness, and fairness in imaging applications. The methodology is validated through effectiveness and composition metrics.

Deep structural causal models for tractable counterfactual inference

Nick Pawlowski, Daniel C. Castro, Ben Glocker

NeurIPS, 2020

This paper introduces Deep Structural Causal Models (DSCMs), a framework combining deep learning with structural causal models to enable tractable counterfactual inference. By leveraging normalizing flows and variational inference, DSCMs support all three levels of Pearl's causality ladder—association, intervention, and counterfactuals—demonstrated through synthetic and real-world imaging case studies.

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Our team

Who we are

We are a team of AI researchers from the Department of Computing at Imperial College London. Over the last five years, we have developed one of the most advanced methodologies for high-fidelity image synthesis powered by causal generative AI.

We have strong expertise in computer vision and medical imaging applications. And we love to collaborate.