Key result
Novel lock-in photoplethysmographic imaging successfully maps dynamic cardiovascular pulse waves and detects subtle autonomic responses.
A novel photoplethysmographic imaging method using lock-in amplification of video frames enables high spatial resolution visualization of cardiovascular pulse waves.
May advance non-contact cardiovascular monitoring; leaves open clinical validation before practice adoption.
We present a new method of formation photoplethysmographic images with high spatial resolution from video recordings of a living body in the reflection geometry. The method (patent pending) is based on lock-in amplification of every pixel of the recorded video frames. A reference function required for synchronous detection of cardiovascular pulse waves is formed from the same frames. The method is featured by ability to visualize dynamic changes in cardiovascular pulse wave during the cardiac (or respiratory) cycle. We demonstrate that the system is capable to detect the minimal irritations of the body such as gentle scratching of the skin by own finger.
No takes yet. Share an insight, caveat, or question.
Kamshilin et al. (2011) studied this question. Photoplethysmographic imaging with lock-in amplification was evaluated on Visualization of dynamic changes in cardiovascular pulse wave and detection of minimal irritations. A new photoplethysmographic imaging method based on lock-in amplification successfully visualized dynamic changes in cardiovascular pulse waves and detected minimal body irritations.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: