Figure 3

Co-registered, morpho-molecular information of OCT and Raman maps on a bladder biopsy with mixed epithelium and collagen signals. Enface Raman map indicates homogeneous distribution of epithelial (a) and collagen (b) signals, but no significant lipid contributions (c). The collagen signals are reduced in locations where the epithelial signal is increased and vice versa. For comparison, the enface OCT maximum intensity projection of ten slices from a depth of 90–120 µm is shown (d). The higher signal intensity in the OCT correlates quite well with the higher intensity in collagen signal (b). While a reduced intensity correlates better with the increase of epithelium tissue. The maximum intensity projections of ten cross-sectional OCT B-scans, from positions indicated by dashed and dotted lines in the images, are plotted in (e,f). The co-registered molecular Raman information (E: Epithelium, C: Collagen, L: Lipid) is plotted above, and shows a good overlap between the signals, i.e. brighter OCT signal overlapping with the collagen signals, while the darker areas correlate to the epithelial signals. For comparison, H&E image (g) of the same biopsy shows both collagen and epithelium regions, indicated by red and green arrows corresponding to epithelium and collagen Raman signals respectively. The epithelium is indicated with a red arrow. The green arrow is indicating the lamina propria with high collagen content. A mechanical artifact and the deeper lamina propria layer of the bladder wall are additionally visible. Scale bars: 250 µm.