Exploiting Causality Signals in Medical Images: A Pilot Study with Empirical Results

We present a new method for automatically classifying medical images that uses weak causal signals in the scene to model how the presence of a feature in one part of the image affects the appearance of another feature in a different part of the image. Our method consists of two components: a convolutional neural network backbone and a causality-factors extractor module. The latter computes weights for the feature maps to enhance each feature map according to its causal influence in the image's scene. We can modify the functioning of the causality module by using two external signals, thus obtaining different variants of our method. We evaluate our method on a public dataset of prostate MRI images for prostate cancer diagnosis, using quantitative experiments, qualitative assessment, and ablation studies. Our results show that our method improves classification performance and produces more robust predictions, focusing on relevant parts of the image. That is especially important in medical imaging, where accurate and reliable classifications are essential for effective diagnosis and treatment planning.