Medical augmented reality combines both real and virtual three-dimensional images to assist in medical procedures or education. Most commonly, augmented reality technologies are used to provide doctors with images of the inside of a patient's body for use in surgery. The same or similar technologies allow medical students to practice procedures on manikins or cadavers. Another type helps the patients themselves to visualize what is happening in their bodies.
Minimally invasive surgical techniques allow doctors to perform surgery without making large incisions. Medical augmented reality is an essential tool to allow this to happen. Often, a patient's Magnetic Resonance Imaging (MRI) results, ultrasounds or other three-dimensional records are combined with real-time images of the surgeon's actions. The combined images can be viewed through a Head Mounted Display (HMD), which the surgeon wears to mimic natural sight.
Medical students or surgical interns can use medical augmented reality to practice surgical techniques. The technology for this is much the same as that used in minimally invasive surgery. Instead of an actual patient's records, however, the student might practice by using a manikin with generic images of the inside of a person's body. The student could then manipulate the virtual images to provide a highly accurate simulation of performing actual surgeries. For even greater similarity, the same thing can also be done using a cadaver instead of a manikin.
Since medical augmented reality can provide such a detailed, vivid picture of the inside of a person's body, it can also be used to help educate patients. A person might, for instance, stand in front of a screen that would provide images of the muscles, skeleton or other effected systems in the body. This image may move when the person moves, or in response to the doctor's manipulation. The doctor can use these images to help patients understand what is going wrong in their bodies, and what needs to be done to correct the problems. This technology serves a function similar to a scale model of a knee joint, for instance, but with greater interactivity.
The field of medical augmented reality is one that is still growing. Other uses of these same technologies have been proposed, but had not been implemented as of 2011. For example, it may be possible to create HMD software, which will allow doctors to see a patient's entire medical history at a glance by superimposing images of previous injuries or illnesses on the patient's body.