Infrared Imaging in Complex Regional Pain Syndrome

Sympathetic blocks are clinically used to diagnose and treat sympathetically mediated pain. Despite the frequent use of these blocks, there remains a need for an objective method to determine the achievement of a sympathetic block in the clinical setting. Current clinical practice assess the success of a sympathetic block by observation of clinical signs of sympathetic blockade. These signs include monitoring skin temperature, pulse amplitude, blood oxygen, or any combination of these methods. However, clinical signs of sympathetic blockade often demonstrate an unpredictable or delayed response and can make monitoring difficult. Therefore, it is necessary to develop an objective monitoring method that is reliable, rapid response, and not affected by the other confounders. One potential method is the use of thermal camera imaging (FLIR). Such a monitor could increase procedural accuracy and efficiency, thus improving patient care. To plan the prospective treatment options, objective confirmation of successful sympathetic block is essential to differentiate sympathetically mediated pain (SMP) versus sympathetically independent pain (SIP). In this context, utilization of a monitor with a rapid response and easy clinical applicability, would serve as an objective endpoint for evaluating sympathetic blockade both clinically and for future research. Therefore, this research proposal aims to investigate the infrared (FLIR) thermal camera as an objective method for determining the achievement of sympathetic block in the clinical setting.