Detection of localized pulsatile motion in cutaneous microcirculation by speckle decorrelation optical coherence
Peijun Gong1, Christian Heiss2,3, Danuta M Sampson4,5
1The University of Western Australia, Optical+Biomedical Engineering Laboratory, Department of Electr, Australia.
Insights
Speckle decorrelation OCTA can visualize peripheral microvascular pulsatility in human skin. This technique offers new insights into cardiovascular health and disease, with specific protocols for different imaging needs.
Area of Science:
- Biomedical Optics
- Cardiovascular Physiology
- Medical Imaging
Background:
- Pulsatility is a key cardiovascular feature.
- Peripheral microvascular pulsatility is not well-characterized.
- Understanding pulsatility aids in studying arterial stiffening, vascular aging, and cardiovascular disease.
Purpose of the Study:
- To assess speckle decorrelation OCTA for visualizing peripheral pulsatility.
- To evaluate noncontact and contact scanning protocols for OCTA imaging.
- To investigate pulsatility in human skin microvasculature.
Main Methods:
- Speckle decorrelation optical coherence tomography angiography (OCTA) was employed.
- Noncontact and contact scanning protocols were tested.
- Imaging was performed on vessel-free tissue and peripheral human skin microvasculature.
Main Results:
- Distinct pulsatile patterns were observed in both vessel-free tissue and microvessels.
- Pulsatile signatures correlated with pulsatile pressure and blood flow.
- OCTA pulse rates agreed with pulse oximetry, confirming hemodynamic reflection.
Conclusions:
- Speckle decorrelation OCTA is suitable for measuring peripheral cutaneous pulsatility.
- Specific protocols are defined for noncontact (vessel-free tissue) and contact (microvessels) imaging.
- Further research into microcirculation using these OCTA methods is recommended.
Significance:
Pulsatility is a vital characteristic of the cardiovascular system. Characterization of the pulsatility pattern locally in the peripheral microvasculature is currently not readily available and would provide an additional source of information, which may prove important in understanding the pathophysiology of arterial stiffening, vascular ageing, and their linkage with cardiovascular disease development.
Aim:
We aim to confirm the suitability of speckle decorrelation optical coherence tomography angiography (OCTA) under various noncontact/contact scanning protocols for the visualization of pulsatility patterns in vessel-free tissue and in the microvasculature of peripheral human skin.
Results:
Results from five healthy subjects show distinct pulsatile patterns both in vessel-free tissue with either noncontact or contact imaging and in individual microvessels with contact imaging. Respectively, these patterns are likely caused by the pulsatile pressure and pulsatile blood flow. The pulse rates show good agreement with those from pulse oximetry, confirming that the pulsatile signatures reflect pulsatile hemodynamics.
Conclusions:
This study demonstrates the potential of speckle decorrelation OCTA for measuring localized peripheral cutaneous pulsatility and defines scanning protocols necessary to undertake such measurements. Noncontact imaging should be used for the study of pulsatility in vessel-free tissue and contact imaging with strong mechanical coupling in individual microvessels. Further studies of microcirculation based upon this method and protocols are warranted.
