Correlation between the uptake of sodium fluorescein in the tissue and xenon-133 clearance and laser Doppler fluxmetry in measuring changes in skin circulation.

We have measured the plantar forefoot skin circulation by the uptake of sodium fluorescein (fluorescein flowmetry), 133Xe clearance and laser Doppler fluxmetry in 24 healthy subjects and correlated measurements under basal conditions and after provocation by alcohol intake and application of external heat. To assess the change in skin circulation between the initial measurement at rest and the second measurement after provocation, the coefficient of correlation (r) of the fluorescein flowmetry to the fast slope of the 133Xe elimination curve was 0.46 (p < 0.05), to the slow slope of the 133Xe elimination curve 0.66 (p < 0.001) and to laser Doppler fluxmetry 0.86 (p < 0.001). The coefficient of correlation (r) of the fluorescence appearance time to fluorescein flowmetry was 0.65 (p < 0.001), to the fast slope of the 133Xe elimination curve 0.14 (p = 0.42), to the slow slope of the 133Xe elimination curve 0.47 (p < 0.05) and to laser Doppler fluxmetry 0.63 (p < 0.001). The uptake of sodium fluorescein as measured by fluorescein fluxmetry correlates well with both 133Xe clearance and laser Doppler fluxmetry in assessing a change in skin circulation in healthy humans. The fluorescence appearance time also correlates to the slow slope of the 133Xe elimination curve and to laser Doppler fluxmetry though to a lesser extent.