Microcirculation, especially skin microcirculation, is a window towards systemic vascular function in magnitude and underlying mechanisms. Different techniques have been developed to assess the microcirculation. Among these techniques, laser technology is used to perform non-invasive microvascular assessments. Although this technique is widely used, different methodological issues remain. This study aims at defining the way to use lasers for clinical use.

Inclusion Criteria:

• age > 18years old
• subject without any known cardiovascular disease

Exclusion Criteria:

• pregnancy

Residents of France