Optical coherence tomography microangiography for monitoring the response of vascular perfusion to external pressure on human skin tissue

Abstract

Abstract. Characterization of the relationship between external pressure and blood flow is important in the examination of pressure-induced disturbance in tissue microcirculation. Optical coherence tomography (OCT)-based microangiography is a promising imaging technique, capable of providing the noninvasive extraction of functional vessels within the skin tissue with capillary-scale resolution. Here, we present a feasibility study of OCT microangiography (OMAG) to evaluate changes in blood perfusion in response to externally applied pressure on human skin tissue in vivo. External force is loaded normal to the tissue surface at the nailfold region of a healthy human volunteer. An incremental force is applied step by step and then followed by an immediate release. Skin perfusion events including baseline are continuously imaged by OMAG, allowing for visualization and quantification of the capillary perfusion in the nailfold tissue. The tissue strain maps are simultaneously evaluated through the available OCT structural images to assess the relationship of the microcirculation response to the applied pressure. The results indicate that the perfusion progressively decreases with the constant increase of pressure. Reactive hyperemia occurs right after the removal of the pressure. The perfusion returns to the baseline level after a few minutes. These findings suggest that OMAG may have great potential for quantitatively assessing tissue microcirculation in the locally pressed tissue in vivo.

In vivo dual-modality photoacoustic and optical coherence tomography imaging of human dermatological pathologies

“…Imaging of microcirculation under psoriatic conditions, using ultrahigh-sensitive optical microangiography (UHS-OMAG) was reported by Qin et al [9]. The OMAG as a recent extension of OCT has been used to monitor vascular perfusion in the nail fold [10]. Doppler OCT (DOCT), another functional extension of OCT, has been used for imaging microvasculature as well [11].…”

Quantitative characterization of mechanically indented in vivo human skin in adults and infants using optical coherence tomography

“…For instance, optical coherence elastography can be used to evaluate the viscoelastic properties of tissue components, and Doppler OCT or optical microangiography can be applied to monitor the vascular distribution. [1][2][3]38,39 Optical coherence microscopy (OCM) can be used to detect structural, biomechanical, and hemodynamics of skin at the cellular level. 40,41 Moreover, OCM can be integrated with multiphoton and fluorescence lifetime imaging microscopy to provide molecular contrast, infer cellular metabolism state, and monitor the cell dynamics in skin tissue.…”

Application of cmOCT and continuous wavelet transform analysis to the assessment of skin microcirculation dynamics

“…27 The combination of OMAG with the PORH reactive test has been described previously as an optimal method for providing quantitative functional data of the human peripheral skin microcirculation. 28 Another technique for the in vivo imaging of the microcirculation is correlation mapping OCT (cmOCT). This method employs correlation coefficient statistics to determine blood flow from the intensity of the reflected OCT signal, 9,10 taking advantage of the time-varying speckle of moving scatters in skin regions containing active blood vessels and the constant reflectance of the stationary scatters in the bulk tissue lacking of blood vessels.…”