Virtual Reality To Help Train Surgeons

A virtual reality (VR) system is under development that will allow trainee surgeons to see a high resolution 3D image of a human body, scaled to any dimensions. As they go through a procedure they will feel the pressure of an instrument as it cuts through tissue. They will know when they hit a bone or make a wrong move.

The system will be one application of the revolutionary Haptic (touch feedback) Workbench, developed by CSIRO and the Advanced Computational Systems Cooperative Research Centre (ACSys).

The Haptic Workbench is able to simulate the sense of touch so that the operator feels as well as sees the virtual object.

"What makes the system really special is that the objects it displays can be felt and manipulated. It is this ‘haptic' aspect that allows delicate and critical procedures to be realistically simulated," says CSIRO scientist Duncan Stevenson.

The technology is of great interest to the Royal Australasian College of Surgeons (RACS) who are planning a virtual surgery training centre.

"At a recent demonstration, RACS members were amazed to feel a syringe pop through skin and vein and then to see it fill with blood, because it was so true to life," Mr Stevenson says.

During the "operations," trainees' progress can be monitored, measuring the pressure and angle of incisions, tissue damage and other indicators with an accuracy not currently possible.

"Surgeons will know exactly what aspects of surgery they need to work on," says Mr David Storey of the RACS. "This will be an enormous benefit."

Mr Storey says that surgical training will be revolutionised by these technologies.

"Surgeons are, of course, trained very well by current methods but the VR solution will be less expensive of time and resources and offer some revolutionary possibilities."

"By using actual patient data to generate the virtual image, a surgeon can rehearse a complex surgical procedure on a precise simulation of an individual patient."

"Experienced surgeons will be able to update their skills so new, life-saving surgical techniques may be introduced sooner and applied more widely."

The workbench combines a mirrored 3D imaging system with a robotic arm which is both the input and the haptic feedback device. Wearing 3D glasses the user sits at the workbench and takes hold of the instrument at the end of the robotic arm. This instrument can take the form of a pen, a tool, a scalpel or anything the system programs it to be.

Powerful, miniature motors which control the way the robotic arm responds to movement create resistance which gives the user the sensation that they are really touching an object or person.

"The arm is actually stronger than you are. So if the software says you can't do something - like push the needle through bone - there is simply no way you can force the arm to do it."

Mr Stevenson says that without haptic feedback, no system can expect to accurately mimic reality.

"Have you ever tried to write your name on a piece of paper held vertically in the air? It's almost impossible! But once you have something to push against, it's easy."

The 3D mirror system means that objects appear to sit on the bench rather than in a computer monitor which greatly adds to the realism.

"Having just the hands involved makes for a more focussed experience," says Duncan Stevenson. "The mind is not distracted by unnecessary inputs so more precise concentration is possible - just like the intense concentration needed in the operating theatre."

There's still plenty of work ahead for the research team before VR training of surgeons becomes routine.

"We need to acquire a huge amount of anatomical and physical data to generate the 3D body images," says Mr Stevenson, "then the software systems for specific types of surgery need to be developed. "

Many other potential applications for these haptic VR systems exist in fields including design, manufacturing, mining, aerospace, chemicals and biotechnology.

More information: Rosie.Schmedding@nap.csiro.au

Web: http://www.cmis.csiro.au/imvs/