Correlation of infrared thermography and skin perfusion in Raynaud patients and in healthy controls

BackgroundWe aimed to investigate the correlation of infrared thermography (IT) with laser Doppler perfusion imager (LDPI) among patients with primary Raynaud's phenomenon and healthy controls.MethodsForty-seven individuals were included: we examined 25 patients with primary Raynaud's phenomenon and 22 age and gender matched healthy controls. IT of the volar surface of the subjects' left hands was performed to record skin temperature while skin perfusion of the same area was determined using LDPI. All measurements were obtained at room temperature (baseline measurements) and following standardized cold provocation.ResultsGood correlation of baseline measurements was found between IT and LDPI in primary Raynaud patients and healthy controls (r = 0.868, p < 0.0001 vs. r = 0.790, p < 0.0001). Following cold challenge, correlation was weaker in both groups (r = 0.742 vs. r = 0.766, p < 0.0001). Correlation after cold provocation was statistically significant among patients with primary Raynaud's phenomenon in contrast to controls (Chi Quadrat, p = 0.023 vs. p = 0.306).ConclusionA significant correlation was found between IT and LDPI in primary Raynaud patients and in healthy controls (r = 0.868 and r = 0.742, both p < 0.0001). Following cold provocation, correlation decreases in both groups. Thus, at room temperature IT might substitute for skin perfusion measured by LDPI.