title: Laser speckle contrast imaging: age-related changes in microvascular blood flow and correlation with pulse-wave velocity in healthy subjects.
abstract: In the cardiovascular system, the macrocirculation and microcirculation—two subsystems—can be affected by aging. Laser speckle contrast imaging (LSCI) is an emerging noninvasive optical technique that allows the monitoring of microvascular function and can help, using specific data processing, to understand the relationship between the subsystems. Using LSCI, the goals of this study are: (i) to assess the aging effect over microvascular parameters (perfusion and moving blood cells velocity, MBCV) and macrocirculation parameters (pulse-wave velocity, PWV) and (ii) to study the relationship between these parameters. In 16 healthy subjects (20 to 62 years old), perfusion and MBCV computed from LSCI are studied in three physiological states: rest, vascular occlusion, and post-occlusive reactive hyperaemia (PORH). MBCV is computed from a model of velocity distribution. During PORH, the experimental results show a relationship between perfusion and age (R(2) = 0.67) and between MBCV and age (R(2) = 0.72), as well as between PWV and age at rest (R(2) = 0.91). A relationship is also found between perfusion and MBCV for all physiological states (R(2) = 0.98). Relationships between microcirculation and macrocirculation (perfusion-PWV or MBCV-PWV) are found only during PORH with R(2) = 0.76 and R(2) = 0.77, respectively. This approach may prove useful for investigating dysregulation in blood flow.
authors.affiliation: University of Angers, LARIS-Laboratoire Angevin de Recherche en Ingénierie des Systémes, 62 Avenue Notre-Dame du Lac, 49000 Angers, France.
authors.forename: Adil
authors.initials: A
authors.lastname: Khalil
authors.affiliation: University of Angers, LARIS-Laboratoire Angevin de Recherche en Ingénierie des Systémes, 62 Avenue Notre-Dame du Lac, 49000 Angers, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Humeau-Heurtier
authors.affiliation: Pôle Imagerie Médicale et Explorations Fonctionnelles, Inserm CIC 1414, Hospital Pontchaillou of Rennes, University of Rennes 1, 35033 Rennes Cedex 9, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Mahé
authors.affiliation: University of Angers, Hospital of Angers, Laboratoire de Physiologie et d'Explorations Vasculaires UMR CNRS 6214-INSERM 1083, 49033 Angers Cedex 01, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Abraham
mesh_terms: D000328:Adult; D000367:Age Factors; D000375:Aging; D001783:Blood Flow Velocity; D001794:Blood Pressure; D003952:Diagnostic Imaging / Q000379:methods; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D006940:Hyperemia; D007834:Lasers; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D010477:Perfusion; D063177:Pulse Wave Analysis; D012542:Scattering, Radiation; D012867:Skin / Q000098:blood supply*; D055815:Young Adult