Machine Learning–Based Image Processing in Radiotherapy

In radiation therapy, high-energy beams, such as X-rays or particle beams, are directed at a tumor. These beams, typically invisible to the naked eye, are delivered from a machine outside the body in what is known as external beam radiation therapy. As a result, advanced imaging techniques are used to precisely locate the tumor within the body and guide the delivery of radiation. Significant progress in computer vision and machine learning has led to substantial improvements in image-guided radiotherapy, enhancing treatment accuracy by visualizing and quantifying patient anatomical information and streamlining the treatment workflow through automation. Moreover, deep learning has elevated performance in artificial intelligence beyond conventional machine learning and image processing techniques. In this chapter, we introduce the application of deep learning–based image processing in radiotherapy and discuss the technologies that will be essential for the future of radiotherapy.