Quantification of capillary blood cell flow using reflectance confocal microscopy

Area of Science:

• Dermatology
• Microcirculation Research
• Medical Imaging Technology

Background:

• In vivo reflectance confocal microscopy (IVCM) offers a novel approach to visualize skin microcirculation.
• Standardization of quantitative blood cell flow (QBCF) measurements using IVCM remains a challenge.
• Current manual QBCF assessment methods lack consistent reproducibility.

Purpose of the Study:

• To evaluate the inter-investigator and intra-capillary reproducibility of manual QBCF measurements from IVCM videos.
• To investigate the utility of a software-based approach for QBCF measurement.
• To assess the sensitivity of QBCF measurement methods to vascular occlusion tests.

Main Methods:

• Manual QBCF measurement reproducibility was assessed across 107 IVCM videos.
• Intra-capillary reproducibility was compared between manual and two semi-automatic Image J software methods.
• The 'peaks of luminous intensity' semi-automatic method was applied during vascular occlusion tests.

Main Results:

• Manual QBCF measurement demonstrated poor inter-investigator reproducibility (Pearson's coefficient <0.5).
• The 'peaks of luminous intensity' method exhibited good intra-capillary reproducibility.
• This software-based method proved sensitive in detecting changes during vascular occlusion.

Conclusions:

• The 'peaks of luminous intensity' method using Image J software shows potential for standardized QBCF measurement.
• Future development should focus on real-time QBCF measurement software based on this technique.
• This approach could significantly advance the quantitative analysis of skin microcirculation via IVCM.