Chronic Pain Science

• Reference: PHE van der Veen. 1989 PHILIPS THERMOGRAPHY.
• Two infra-red Thermography images. The black parts are Cold Spots of Pain.
• The left before PTX medication and the right after.
• After PTX the pain is gone...

• Veen PHE van der. Infrared thermography for pain influenced by a Xanthine derivative: An attempt to assess chronic pain objectively. Thermology international Vol 24 (2014), No. 2: 39-48 Available at:
• http://www.uhlen.at/thermology-international/index.php

SUMMARY BACKGROUND:
There have been no diagnostic options for objective pain diagnostics until recently. Infrared thermography seemed to be a promising technique that could be applied, especially when following the progress of a case. The goal of the study was to check if infrared thermography could be of use to objectify pain sites and pain sensation.
METHODS:
During this study, 63 temperature measurements were done in patients suffering chronic pain in one extremity. They were followed during the pre- and post-treatment of Pentoxifylline (PTX). The contra-lateral side of each patient was used as the control. The temperature of the pain site and the symmetrical contra-lateral extremity were measured prior to and after treatment. Only the change in pain sensation was registered, using gradations of: reduced, equivalent, or worse.
RESULTS:
There were 53 cold spots and 10 hot spots out of the 63 pain sites measured. There was a significant left-right difference (p = 0.001). After treatment with PTX there was no longer any significant left-right difference (p = 0.061), whereas the temperature on the pain side increased significantly (p < 0.001). There was a significant correlation between the change in temperature as measured by the thermographically image and the pain sensation (p < 0.001, Spearman's rank correlation coefficient: 0.5567).
CONCLUSIONS:
Infrared thermography and PTX are probably possible instruments applicable for assessing chronic pain lacking any anatomical substrate. The majority of the pain sites that cannot be seen by the naked eye (>70%) are colder than their surroundings, which confirms studies performed previously The impact of PTX on this study suggests that Prostaglandin and Cytokine have an effect on the development of these pain sites.

December 2014.