Deep Blur Multi-Model (DeepBlurMM) -- a strategy to mitigate the impact of image blur on deep learning model performance in histopathology image analysis

AI-based analysis of histopathology whole slide images (WSIs) is central in computational pathology. However, image quality, including unsharp areas of WSIs, impacts model performance. We investigate the impact of blur and propose a multi-model approach to mitigate negative impact of unsharp image areas. In this study, we use a simulation approach, evaluating model performance under varying levels of added Gaussian blur to image tiles from >900 H&E-stained breast cancer WSIs. To reduce impact of blur, we propose a novel multi-model approach (DeepBlurMM) where multiple models trained on data with variable amounts of Gaussian blur are used to predict tiles based on their blur levels. Using histological grade as a principal example, we found that models trained with mildly blurred tiles improved performance over the base model when moderate-high blur was present. DeepBlurMM outperformed the base model in presence of moderate blur across all tiles (AUC:0.764 vs. 0.710), and in presence of a mix of low, moderate, and high blur across tiles (AUC:0.821 vs. 0.789). Unsharp image tiles in WSIs impact prediction performance. DeepBlurMM improved prediction performance under some conditions and has the potential to increase quality in both research and clinical applications.