NASA 'Software Scalpel' Helps Doctors Practice Operations

Using the new approach, a physician wearing 3-D glasses can see an image of a patient's head from all angles on a computer monitor, or on the surface of a large "immersive virtual reality work bench." Virtual reality is a computer-created environment that simulates real-life situations.

"To predict what the result will be in a real operation, the surgeon uses a computer mouse to mark the incision location and to ask the computer to 'cut' bone," said Muriel Ross of NASA's Ames Research Center, Moffett Field, CA. Ross is director of the Ames Center for Bioinformatics, which uses computer technology to improve medical practices. "The doctor can then remove the simulated piece of bone or can place it at a new angle or in a new position."

"Because some patients have severe injury to the head or diseases such as cancer, there are times when physicians must rebuild a person's head or face," Ross said.

"We are working on an addition to the scalpel software that will allow us to 'snap' a face back onto the 3-D image of the skull on which a doctor has practiced an operation," she said. "The doctor and the patient can then get a better idea of how the face will look after the actual operation."

"Eventually, we want to provide a virtual tool for surgeons to practice many sorts of surgery," said Aaron Lee, a student from Princeton University, who worked in Ross' lab to develop the Virtual Surgery Cutting Tool.

Each high-fidelity 3-D picture of a human head is known as a 'reconstruction,' or a computerized object. "The computerized reconstructions are highly accurate, 3-D visual models of the head, but can be made of any part of the human body," said Ross.

In the technique, a series of computed tomography (CT) scans are combined to make the 3-D image using Reconstruction of Serial Sections (ROSS) software previously developed by researchers at the Ames Center for Bioinformatics. The Ames team also combined features of the ROSS software with the CT scan version to reconstruct a breast tumor from magnetic resonance images.

The NASA Center for Bioinformatics at Ames is part of a larger National Biocomputation Center established by NASA and Stanford University, Palo Alto, CA, according to Ross. "The new center is a national resource to further the use of virtual reality in medicine," Ross said.

The Ames bioinformatics team is working on a variety of virtual reality computer tools to aid in complex facial reconstructive surgery and other procedures. Surgeons can use the big-screen workbench, special gloves, as well as computer tracking wands and other devices to manipulate 3-D computer images of patients.

The team is also interested in working with mastectomy patients who require breast reconstruction, and with children who need reconstructive surgery to correct deformities of the head and face. Eventually, software systems could be used in other medical specialties or surgical procedures.

In the future, virtual reality will allow surgeons to rehearse a great many complex procedures before operations, according to Ross. The team expects that, eventually, virtual reality will be a powerful teaching tool for medical students. A digital library of computerized "virtual patients" will be created that physicians can use to share information about uncommon procedures, according to researchers.