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Updated: Jun 25, 2026
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Laser Doppler Perfusion Imaging in the Mouse Hindlimb
Published on: April 18, 2021
Pulse transit times to the capillary bed evaluated by laser Doppler flowmetry
Alan Bernjak1, Aneta Stefanovska
1Faculty of Electrical Engineering, University of Ljubljana, Trzaska 25, 1000 Ljubljana, Slovenia. Physics Department, Lancaster University, LA1 4YB, UK.
Physiological Measurement
|February 10, 2009
Summary
This study introduces a new method to measure pulse transit time (PTT) in the microcirculation using laser Doppler flowmetry. This non-invasive technique allows for simultaneous assessment of both macro and microvascular health.
Area of Science:
- Cardiovascular Physiology
- Biomedical Engineering
- Non-invasive Diagnostics
Background:
- Pulse transit time (PTT) is a non-invasive index for arterial distensibility.
- Current PTT methods primarily assess larger arteries.
- Microcirculatory assessment is crucial for comprehensive vascular health evaluation.
Purpose of the Study:
- To evaluate pulse arrival time (PAT) to the capillary bed (microcirculation).
- To investigate the relationship between microcirculatory PAT and arterial PAT.
- To introduce a method for measuring PTT through the microcirculation.
Main Methods:
- Cardiac-induced pulse waves detected in skin microcirculation via laser Doppler flowmetry (LDF).
- Simultaneous PAT measurements to microcirculation (four extremities) and radial artery (fingertip).
- Electrocardiogram (ECG) used as a reference for timing.
Main Results:
- Both microcirculatory and arterial PAT correlated with heart rate and age.
- Microcirculatory PAT was sensitive to local skin perfusion changes induced by cooling.
- A novel measure for microcirculatory PTT was successfully introduced.
Conclusions:
- Combining LDF and pressure measurements allows simultaneous characterization of macro and microvasculature.
- Microcirculatory assessment, including endothelial function, can be derived from responses to perfusion perturbations.
- This approach offers valuable insights into microcirculatory dynamics and vascular health.
