Brain Imaging Biomarker of Pain: I see how you feel

Our perception of biomarkers tends to be limited to the realm of measures that provide information about disease and drug activity.  In fact, biomarkers can provide a means to assess additional biological processes relevant to patient well being such as anxiety and pain.  In paper published in the September 13^th issue of PLoS One (link), a team of the Department of Anesthesia, Stanford University describes a new functional MRI-based (fMRI) biomarker for the identification of pain.  Because the sensation of pain can be subjective and can occur in the absence of detectable injury, the standard for assessing pain is based on patient self report.  While this traditional measure is readily assessable, it does not differentiate between the sensory and the psychological components of pain perception.  In addition, patient self reported pain assessment is impossible in individuals who are not able to communicate.  Therefore, development of an objective biomarker of pain is of great interest to the medical community. 

The team at Stanford performed a pilot study involving 24 individuals who were monitored by fMRI while being subjected to painful and non-painful thermal stimuli.  Using the results from the first 8 volunteers, the team used Support Vector Machine learning to develop a predictive model that then validated on the remaining 16 individual volunteers.  In this setting, the model accurately identified the type of stimulus with 81 % accuracy.

While the size of this study is not sufficient to draw definitive conclusions, it is tempting to speculate that the future of pain management in patients who are unable to communicate may improve dramatically

Thierry Sornasse for Integrated Biomarker Strategy