microvascular tests
Thermal Imaging
Thermal imaging or “thermography” uses a heat-sensitive camera to measure the temperature of the fingers. This is performed in association with a mild cooling of the hands in water for one minute. The rate at which the fingers become warm again after this cooling provides us with useful information about the tendency of the blood vessels to constrict when the skin is cooled.
Nailfold Capillaroscopy
Nailfold capillaroscopy looks at the capillary blood vessels near the base of the fingernails using a hand-held microscope. A drop of immersion oil is applied to each nailfold to improve the visibility of the capillaries through the skin. The images collected are used to assess whether there are any changes to the appearance of capillary bed, which can be an important clue about the risk of some autoimmune diseases developing in association with Raynaud’s phenomenon.