Distracting patients by immersing them in a virtual world appears to reduce pain, even in the elderly, a new study found.
"I was surprised to see the level of analgesic response that the elderly patients demonstrated, because these subjects had little or no previous experience with video games or virtual reality (VR) distraction, unlike our younger subjects," Dr Sam Sharar, an anaesthesiology professor at Washington University, said.
The VR therapy involves a video game on a head-mounted display developed by Hunter Hoffman, a cognitive psychologist and researcher at the University of Washington.
In the analgesic experiment, 25 adults age 60 and older were randomised to either a low-immersion or a high-immersion VR environment, using a program called SnowWorld.
The high-immersion group moved along a virtual path through an icy canyon populated by snowmen, igloos, penguins, mammoths and fish, viewing it all through a display that blocked most of their vision of the real world.
With the click of a mouse they could toss snowballs at the creatures. Looking around, they could see sky above, canyon walls to their left and right and below they could see a river teeming with mammoths and fish. They also heard sound in stereo, such as the roar of a mammoth when a snowball struck, the splash of a snowball in the river, background music and other effects.
The low-immersion group used the same program with a display that did not block out the real world. Also, the image resolution was reduced (480 x 640 pixels per eye, compared to 1280 x 1024 pixels per eye in high-immersion VR), there were no sound effects, and no game-like interaction with the world - simply a virtual walk on a path through a snowy canyon.
Dr Sharar's team performed two thermal simulations of the pain of lumbar puncture for 30 seconds, once while subjects were not immersed in the VR program, and again when they were.
"Results showed a significant reduction (p<0.05) in sensory, emotional, and cognitive pain components with VR treatment of either kind compared to baseline," the researchers said in the abstract for their presentation. They add, however, that subjective analgesia was significantly greater in the high-immersion VR group for all three domains of the pain experience.
VR may be just as effective at controlling pain as an intravenous dose of hydromorphone, according to a study that Dr Sharar and his colleagues published in Anaesthesia and Analgesia. And when the two are combined, the effect compounds, the study showed.
The current study did not compare the effect of VR in different age groups, but Dr Sharar has carried out similar, not-yet published studies on college-aged and middle-aged participants and drawn some rough generalisations. The subjective pain reduction was similar in all groups, and even slightly better in the elderly compared to college-aged participants, he says.
This VR therapy is in use now in a handful of US burn centres, and it has also been used in patients with psychiatric disorders such as phobias and symptoms of post-traumatic stress disorder.
The hardware is commercially available and costs about $40,000. Hoffman and his team provide the software free of charge to eligible medical centres, Hoffman said.(Reuters Health, May 2011)