Clinical Evaluation of Medical Image Synthesis: A Case Study in Wireless Capsule Endoscopy

TL;DR

This paper introduces a new protocol for evaluating synthetic medical images, presents a novel high-resolution image generation model, and demonstrates its effectiveness in aiding diagnosis of IBD from Wireless Capsule Endoscopy images.

Contribution

It offers a systematic evaluation protocol, a new variational autoencoder model for high-res image synthesis, and validation with clinical experts for medical image generation.

Findings

TIDE-II produces highly realistic WCE images.

Synthetic images outperform existing models in quality.

Clinicians find the synthetic images useful for diagnosis.

Abstract

Synthetic Data Generation (SDG) based on Artificial Intelligence (AI) can transform the way clinical medicine is delivered by overcoming privacy barriers that currently render clinical data sharing difficult. This is the key to accelerating the development of digital tools contributing to enhanced patient safety. Such tools include robust data-driven clinical decision support systems, and example-based digital training tools that will enable healthcare professionals to improve their diagnostic performance for enhanced patient safety. This study focuses on the clinical evaluation of medical SDG, with a proof-of-concept investigation on diagnosing Inflammatory Bowel Disease (IBD) using Wireless Capsule Endoscopy (WCE) images. Its scientific contributions include a) a novel protocol for the systematic Clinical Evaluation of Medical Image Synthesis (CEMIS); b) a novel variational autoencoder-based model for the generation of high-resolution synthetic WCE images; and c) a comprehensive evaluation of the synthetic images using the CEMIS protocol by 10 international WCE specialists, in terms of image quality, diversity, and realism, as well as their utility for clinical decision-making. The results show that TIDE-II generates clinically plausible, very realistic WCE images, of improved quality compared to relevant state-of-the-art generative models. Concludingly, CEMIS can serve as a reference for future research on medical image-generation techniques, while the adaptation/extension of the architecture of TIDE-II to other imaging domains can be promising.