Augmented reality (AR) is used in many fields including medicine, education, manufacturing, and entertainment. With advances in optics, computer systems, and surgical instruments, AR application to medicine is being vigorously researched. Particularly, as surgery using laparoscopy, endoscopy, or catheterized intervention have increased, AR takes an important role in many medical applications.
AR denotes a technique to combine a real world and virtual objects which are artificially generated digital content by a computer. As another aspect of AR is a registration between the real world and virtual objects, it aims to estimate three-dimensional (3D) position and orientation of virtual objects related to the real world. Therefore, AR can allow the user to see 3D virtual objects superimposed upon the real world. With the help of AR, a surgeon can see hidden organs inside a body and improve the perception of treatment procedure by interacting with the real world. After a brief description of three components of the medical AR, its applications will be presented.