Fig. 4

Variation of (a) contrast and (b) SBR with clearing time in the fluorescence imaging mode. Data series marked by (***) and (*) have p-value \(\le\) 0.001 and p-value \(\le\) 0.05, respectively. c Qualitative visualization of the capillary tubes under fluorescence imaging mode on a normalized scale. Scale bar = 1 mm. Skin tissue surface is marked by the yellow dashed lines