Visually evoked pain and its extinction using virtual reality in a patient with complex regional pain syndrome type II

ABSTRACT: In this case report, we used virtual reality (VR) to explore pain evoked by only the appearance of being touched (rather than actually being touched) in a person with complex regional pain syndrome type II. Furthermore, we explored the degree to which this visually evoked pain could be extinguished by applying exposure principles in VR. In stage 1, we identified 4 specific scenarios where pain was triggered by visually simulated touch (without physical stimulation) and used these scenarios to quantify baseline sensitivity to visuotactile stimulation. In stage 2, the patient undertook a 12-week virtual exposure program, and the visual triggers were reassessed 3 weeks after the commencement and immediately upon completion of the program. At baseline, severe pain and a profound cold sensation were immediately and consistently evoked in concert with visually simulated touch. At 12-week follow-up, only one of the initially provocative visual stimuli triggered pain and only after 60 seconds of repeated stimulation. Unfortunately, the transfer of desensitisation from VR to the real world was limited. This case report describes the phenomena of visually evoked pain. Moreover, it describes the near complete extinguishing of visually evoked pain through virtual graded exposure. How improvements gained in VR might be better transferred to real-word improvements merits further investigation.