Convolutional neural networks for whole slide image superresolution

We present a computational approach for improving the quality of the resolution of images acquired from commonly available low magnification commercial slide scanners. Images from such scanners can be acquired cheaply and are efficient in terms of storage and data transfer. However, they are generally of poorer quality than images from high-resolution scanners and microscopes and do not have the necessary resolution needed in diagnostic or clinical environments, and hence are not used in such settings. The driving question of this presented research is whether the resolution of these images could be enhanced such that it would serve the same diagnostic purpose as high-resolution images from expensive scanners or microscopes. This need is generally known as the image super-resolution (SR) problem in image processing, and it has been studied extensively. Even so, none of the existing methods directly work for the slide scanner images, due to the unique challenges posed by this modality. Here, we propose a convolutional neural network (CNN) based approach, which is specifically trained to take low-resolution slide scanner images of cancer data and convert it into a high-resolution image. We validate these resolution improvements with computational analysis to show the enhanced images offer the same quantitative results. In summary, our extensive experiments demonstrate that this method indeed produces images that are similar to images from high-resolution scanners, both in quality and quantitative measures. This approach opens up new application possibilities for using low-resolution scanners, not only in terms of cost but also in access and speed of scanning for both research and possible clinical use.