Virtual Reality for Pain Relief: Science Fiction to Medical Therapy
LAS VEGAS — From it's first appearances in books like Aldous Huxley's Brave New World and on television in the series Star Trek, virtual reality has captured the human imagination.
Now the concept has progressed past the realm of the science fiction genre into medical reality and is currently under investigation as potential therapy for a wide range of conditions from addiction to autism to posttraumatic stress disorder and now pain management.
“One of the best ways to alleviate pain is to introduce a distraction,” said Theresa Mallick-Searle, MS, ANP-BC, of the Division of Pain Medicine at Stanford Health Care. “Because virtual reality immerses users in a 3-dimensional computer-generated world, it is uniquely situated to distract patients from their pain.”
A small but growing body of evidence suggests that virtual reality distraction is effective for reducing pain, according to Ms. Mallick-Searle. In several studies, burn patients undergoing wound care reported a significant decrease in pain when they engaged in a virtual reality program called SnowWorld.1,2
Developed by researchers at the University of Washington's Harborview Burn Center in Seattle, SnowWorld is an immersive virtual reality experience in which patients interact with the virtual world by throwing snowballs at a cast of characters including snowmen, robots, and penguins that respond with 3-dimensional visual and sound effects when hit.
The concept is to use the experience generated by the fiberoptic virtual-reality helmet to direct patients' conscious attention away from the common occurrence of reliving the original burn experience during wound care.
Initial findings are encouraging and suggest that the technology goes beyond simply changing the way patients interpret incoming pain signals to directly effect neuromodulation.
In a 2011 study by Maani et al published in the Journal of Trauma, 12 US soldiers who sustained burns during combat attacks involving explosive devices in Iraq or Afghanistan received half of their severe burn wound cleaning procedure (approximately 6 minutes) with standard-of-care pharmacologic therapies and half while in the SnowWorld virtual reality experience (treatment order randomized).
During two pauses in the wound care procedure—once after each 6-minute wound care period with and without virtual reality—each patient completed 3 subjective pain ratings using a graphic rating scale with a range of 0 to 10. Outcomes were as follows after wound care with virtual reality vs without:
- "Worst pain" (pain intensity) dropped from 6.25 of 10 to 4.50 of 10
- "Pain unpleasantness" ratings dropped from "moderate" (6.25 of 10) to "mild" (2.83 of 10)
- "Time spent thinking about pain" dropped from 76% during no virtual reality to 22% during virtual reality
- Patients rated "no virtual reality" as "no fun at all" (<1 of 10) and rated virtual reality as "pretty fun" (7.5 of 10)
- Follow-up analyses demonstrated that virtual reality was especially effective for the 6 patients who scored 7 of 10 or higher (severe to excruciating) on the "worst pain" (pain intensity) ratings
Pain reduction during virtual reality was greatest in patients with the highest pain during wound care without the technology, the researchers found.
In a second study by Hoffman et al published in the Annals of Behavioral Medicine, researchers measured objective physiologic neural correlates of the SnowWorld virtual reality experience using custom-built goggles designed to immerse patients while simultaneously assessing brain activity with functional magnetic resonance imaging (fMRI).
Similar to the findings observed in the previous study, participants reported feeling moderate to severe pain on subjective pain rating scales when pain stimuli were administered with no virtual reality; they reported experiencing much less pain while immersed in SnowWorld.
On fMRI, neural correlates of pain showed 50% or greater, statistically significant reductions in pain-related brain activity in all 5 brain regions studied, including the anterior cingulate cortex, insula, thalamus, and the primary and secondary somatosensory cortices.
“Short-duration, acute episodic pain has really been where this therapy has proven out thus far. There have been some good studies looking at chronic pain, but right now the literature is looking more at favorable outcomes in these patients,” Ms. Mallick-Searle said.
She called for more methodologically sound and statistically well-powered controlled studies to assess the effectiveness of immersive virtual reality distraction therapies in reducing the discomfort associated with a variety of invasive medical procedures and chronic pain conditions.
Ms. Mallick-Searle also noted several barriers to more widespread study and clinical implementation, specifically cost and provider/patient acceptance. Current virtual reality software packages range from freeware to custom equipment worth thousands of dollars.
“We know that immersive virtual reality experiences are effective. The ability to have a clinic that puts patients in an alternate state with virtual reality goggles and tactile devices is cost dependent,” she said.
Patients must also be willing to accept virtual reality as a plausible therapy after having become used to traditional therapies like injections, medications, physical therapy, and acupuncture.
“If you have a practitioner that isn't skilled at delivering virtual reality therapy, then patients are going to be skeptical,” Ms. Mallick-Searle said.
Disclosure: Theresa Mallick-Searle is a member of speaker's bureaus for Allergan and Depomed.
- Maani CV, Hoffman HG, Morrow M, et al. Virtual reality pain control during burn wound debridement of combat-related burn injuries using robot-like arm mounted VR goggles. J Trauma. 2011;71(10):S125-S130.
- Hoffman HG, Chambers GT, Meyer WJ III, et al. Virtual reality as adjunctive non-pharmacologic analgesic for acute burn pain during medical procedures. Ann Behav Med. 2011;41(2):183-191.