It costs Johnson & Johnson nearly $10,000 per VR unit on average. Stanford's Neurosurgical Simulation Center, funded by its parent hospital and outside donors, cost $750,000.
Virtual technology comes in two flavors: a fully immersive experience, in which users see only a computer-generated environment; and mixed reality, in which 3D images are projected onto the physical world.
Physicians already use virtual technology for a variety of medical procedures, including cancer treatment, by creating interactive maps of tumors; and physical therapy, by having patients play games that encourage movement. But in surgery, it has perhaps the greatest potential.
Traditionally, medical students are judged by how long it takes them to perform a procedure. Instead, with VR, medical students can be graded on whether they make a mistake.
"It gives us a way to judge whether the medical student has learned what they are supposed to learn," says Richard Satava, professor emeritus of surgery at the University of Washington in Seattle.
At Stanford, the Neurosurgical Simulation Center resembles a miniature movie theater, including four cinema-quality seats (complete with cup holders) for students and surgeons to sit in while using VR. Spectators can watch on large TV screens mounted on the wall.
In addition to doctors and students, 400 neurosurgery patients have viewed their surgeries in virtual reality before their procedures. "They can immerse themselves in their brain," Stanford's Steinberg says. "It puts them at ease and shows them exactly what we're going to do."