In vivo dynamic light scattering imaging of blood coagulation

Abstract

Physiological blood coagulation/clotting is an essential biological process that is initiated by vessel injury and includes a cascade of enzymatic reactions finalized by fibrin polymerization and clot formation. We utilize dynamic light scattering (DLS) imaging to monitor in vivo red cell mobility as an indicator of blood coagulation. In the course of the experiments, blood flow is arrested using mechanical occlusion, and then laser injury is applied. We demonstrate that the combination of laser injury with DLS imaging on occluded blood vessels (i.e., under static conditions) is suitable to detect even subtle changes of plasma viscosity in the circulatory system, which reflects the process of clot development. This approach is noninvasive and has a relatively simple and easy-to-use technical design. Thus, the proposed methodology provides a promising tool for investigating blood clotting within the vasculature.

In vivo characterization of tumor and tumor vascular network using multi‐modal imaging approach

“…The examples of these techniques include Laser Doppler Flowmetry (LDF) [12], Dynamic Light Scattering (DLS) [13], Diffusing Wave Spectroscopy (DWS) [14,15], Laser Speckle Contrast Analysis (LASCA) [16], Optical Coherence Tomography (OCT) [17], Doppler OCT [18,19], laser-scanning confocal microscopy [20], Spectrally Enhanced Microscopy (SEM) [21], Fluorescent Intravital Microscopy (FIM) [22] and other. While the techniques mentioned above are good for assessment of blood flow and vascular network structure as a stand-alone instruments, at the same time these modalities are quite limited for a comprehensive simultaneous observation of tumor microenvironment, tumor vascular networks and microcirculation monitoring in vivo.…”

In vivo measurement of skin blood microcirculation using diffusing wave correlation technique

“…Anesthetized animals have been placed on the stage of a setup for intravital microscopy with the procedure similar as described in. 33 Briefly, the temporary blood flow interruption (occlusion) is achieved by using a mechanical occluder, which produces a gentle and local mechanical pressure on the area of large arteries and veins within the mouse ear. The duration of occlusion has not exceed 30 min.…”

“…This system is identical to temporal Laser Speckle Contrast Imaging technique and has been well described earlier. 33 DLS imaging is based on the temporal contrast of intensity fluctuations produced from laser speckles that reflected from mouse skin tissues. The laser speckle is an interference pattern produced by the light reflected or scattered from different parts of an illuminated surface.…”

New noninvasive index for evaluation of the vascular age of healthy and sick people

“…4,5 In our previous studies [6][7][8] we measured intravascular mobility of RBC as a natural marker of the effective viscosity of the blood plasma in close proximity to the vascular wall. For this end, we utilized DLS 9 for measurement of the RBC diffusion coefficient under the condition of intermittent stasis.…”