3D vision has been in use for entertainment in years. But now, the revolutionary technology plays an important role in brain surgery.

Fiberoptic scopes act as the doctor's eyes and fingers in an increasing number of procedures. However, looking directly into the body and looking at a flat monitor are totally different.

Dr. Theodore Schwartz, a brain surgeon at the Weill Cornell Medical Center here, believes that being off by the width of a human hair could mean a big difference between life and death.

The difference between a TV screen and 3D is that on TV there is no depth of field, while the 3D technology gives a three-dimensional, life-like image.

The TV gives a photograph of the brain. 3D gives a picture of the brain itself.

Having 3D in the operating room is a big leap because it makes doctors feel that they are sitting on the place where they are operating, Dr. Schwartz added.

He explained that during an operation, doctors slip a thin instrument-a three millimeter chip-into the patient. The instrument has a camera with numerous lenses on the end. It takes the light, divides it into two pathways, then later on reconstructs it digitally.

According to Dr. Schwartz, this is the state of the art among the state of the art.