Comparison of thermography and laser Doppler imaging in the assessment of Raynaud’s phenomenon

• Published in: Microvascular research 2003-07, Vol.66 (1), p.73-76
• Main Authors: Clark, Stuart, Dunn, Graham, Moore, Tonia, Jayson, Malcolm, King, Terence A, Herrick, Ariane L
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Blood and lymphatic vessels; Blood Flow Velocity; Body Temperature; Cardiology. Vascular system; Diseases of the peripheral vessels. Diseases of the vena cava. Miscellaneous; Fingers - pathology; Hand - pathology; Humans; Laser Doppler imaging; Laser-Doppler Flowmetry - methods; Medical sciences; Raynaud Disease - diagnosis; Raynaud Disease - pathology; Raynaud’s phenomenon; Regional Blood Flow; Scleroderma, Systemic - diagnosis; Scleroderma, Systemic - pathology; Skin Temperature; Systemic sclerosis; Temperature; Thermography; Time Factors
• ISSN: 0026-2862; 1095-9319
• DOI: 10.1016/S0026-2862(03)00018-9

The main objective of the study was to compare the techniques of thermographic and laser Doppler imaging in the assessment of digital blood flow. Thermography measures surface temperature; laser Doppler measures microciculatory flow. Seventeen healthy control subjects and 40 patients with Raynaud’s phenomenon (7 primary, 33 secondary to systemic sclerosis) underwent a 20-min acclimatization period at 23°C. Thermographic and then laser Doppler images were taken of the dorsal aspect of both hands, and the procedure was repeated at a room temperature of 30°C. Three regions/values of interest from each hand were chosen for analysis: the dorsum of the hand, the tip of the middle finger, and the “gradient” between these. Thermographic and laser Doppler results correlated poorly. For example, correlations between techniques for the gradient value were as follows: left hand 23°C, r = 0.61; right hand 23°C, r = 0.64; left hand 30°C, r = 0.47; right hand 30°C, r = 0.48. One explanation for these findings is that laser Doppler imaging is more sensitive to blood flow changes and therefore more likely to show inhomogeneities than the highly damped temperature response. Therefore one technique cannot substitute for another.