Fig. 2: Near infrared fluorescence lymphangiography measurement and analysis in mice and humans.

A An example region of interest (red square) in the popliteal lymphatic network in mice during systole and diastole. Peak and valley plot of the ROI showing the change in signal amplitude over time. Spectrogram of the peak and valley plot shows the instantaneous frequency over time. B An example region of interest (red square) in the forearm of a human patient showing the valley and the peak of ICG signal amplitude, with a corresponding peak-and-valley plot and spectrogram at that ROI. C The contraction frequency (from peak and valley analysis), mean intensity (from peak and valley analysis), mean instantaneous frequency (from wavelet analysis), standard deviation of instantaneous frequency (from wavelet analysis), and amplitude (from peak and valley and wavelet analysis) for mouse (left column with blue dots) and human (right column with red dots) lymphangiography (mean +/− SEM, N = 8 mice, 64 measurements, N = 5 humans, 20 measurements). Mouse data are plotted only for baseline position for comparison with human baseline position. D Measured parameters for mouse (left) and human (right data), for peak-and-valley (blue) and wavelet (green) methods showing moderate variation in some parameters by ROI. E The reliability coefficient for mean intensity, wavelet frequency, wavelet instantaneous frequency SD, wavelet amplitude, peak and valley frequency, and peak and valley amplitude for mouse (left) and human (right) by number of ROIs measured for 1 (green line), 2 (red line), and 3 (black line) gravitational positions. As the values are derived from the generalizability study described in the methods, we have extrapolated reliability up to 10 ROIs, though 8 and 4 ROIs were originally measured from mice and humans, respectively.