Artificial Intelligence and Deep Learning for Brachytherapy.

In recent years, Artificial intelligence (AI), specifically deep-learning (DL) based methods, have been employed extensively to solve various problems in brachytherapy. This paper presents a comprehensive literature review on recent developments and applications of AI/DL technologies for different areas in brachytherapy, including image enhancement, registration, segmentation, treatment planning, quality assurance, outcome prediction, etc. The review will emphasize studies addressing unique challenges in brachytherapy, as compared to external beam radiotherapy. Meanwhile, despite exciting achievements, it is also noted that we are still at the early stage of employing AI/DL-technologies to enhance brachytherapy clinical practice. Hence, this paper will also present challenges and future directions. We hope this review will inspire discussions on this topic and trigger future impactful studies to transform technology advancements into healthcare benefits.