Capillaroscopy
Capillaroscopy is used to observe the condition of the small blood vessels that supply the area surrounding the fingernails. Alterations in these capillaries are indicative of rheumatic diseases such as Raynaud’s phenomenon.
General Description
Capillaroscopy is a test that provides real-time imaging of the skin microcirculation. It is a non-invasive procedure used to detect abnormalities in the smallest blood vessels.
To observe the capillaries in the periungual region (around the nail) of the hands—where capillaroscopy is performed—an optical system and a light source are used. By visualizing through the skin, it is possible to assess the size, number, morphology, and distribution of the capillaries supplying the fingers.
When is it indicated?
Capillaroscopy is primarily used in patients with Raynaud’s phenomenon to diagnose vascular damage and other associated pathologies. This technique is useful for detecting autoimmune or inflammatory diseases, particularly Raynaud’s phenomenon, lupus, Sjögren’s syndrome, arthritis, scleroderma, and vasculitis.
How is it performed?
To perform capillaroscopy, a magnification microscope (between 20× and 200×) is placed on the skin at the nailfold of one of the fingers. The ring finger or little finger (fourth and fifth digits) are commonly selected because the skin is thinner and more transparent. To facilitate capillary visualization, a beam of cold light is applied.
In digital capillaroscopy, the most advanced technique, microscopes with magnifications between 200× and 500× are used.
Risks
Capillaroscopy is a test that poses no health risks and does not produce side effects.
What to expect from capillaroscopy
Capillaroscopy is a painless test after which the patient can immediately resume normal activities. Prior to the procedure, the condition of the nails and fingers is assessed. The test may need to be postponed if bruising or wounds are present that could impair adequate visualization of the capillaries.
The room where capillaroscopy is performed is typically maintained at a temperature between 22°C and 25°C to prevent capillary constriction due to cold.
During the procedure, which lasts approximately 10 minutes, the hand should be kept as still as possible.
Results are usually available on the same day as the test. Capillaroscopy is considered abnormal if capillary enlargement (thickening) is observed or if there are abrupt morphological changes. Small hemorrhages may also be detected.
Specialties in which capillaroscopy is requested
Capillaroscopy is a commonly used test in the specialties of Rheumatology and Pediatric rheumatology.
How to prepare
Before undergoing capillaroscopy, it is recommended to remove nail polish and to avoid smoking for at least two hours prior to the procedure.
