Virtual reality is also being developed to help surgeons to carry out operations on patients hundreds of miles away.

Specialists at the Stanford Research Institute in California have pioneered a remote surgery system for the US Army which could mean that doctors will no longer have to work in the front lines.

In the system, which has now been successfully tested on animals, the surgeon "operates" on a virtual image of the patient which is created by video pictures beamed by satellite from tiny cameras mounted on two robotic arms at the side of the real patient.

As the surgeon operates the two instruments on the virtual image, using two mechanical arms in front of him or her, the robotic arms hundreds of miles away follow every movement slavishly and carry out the operation on the real body. When the robot - staffed by paramedics in case of problems - makes a "real" cut, it appears on the image of the patient in front of the surgeon.