Figure 5

Co-registered, morpho-molecular information of OCT and Raman images on a bladder biopsy with high lipid contributions. Enface Raman maps for epithelium (a), collagen (b) and lipid (c), show the presence and distribution of all three components, and specifically very pronounced lipid pools. The enface OCT maximum intensity projection of ten slices from a depth of 150–180 µm (d) indicates black voids, correlating to the same locations as the lipid signals observed in the Raman map (c). Maximum intensity projections of ten cross-sectional OCT B-scans, positions indicated by dashed and dotted lines in the enface image (e, f) with co-registered molecular Raman information (E: Epithelium, C: Collagen, L: Lipid). In both images, the overlap of lipid Raman signals and the black voids in the OCT cross-sections in a depth of ~ 200 µm is visible. The straight vertical line arising from the bottom to the top in (f) is caused by artifacts of the used OCT probe. For comparison, the H&E image of the biopsy, where the blue arrows indicate the identified lipid pools, is shown in (g). Here, epithelium (red arrow), lamina propria (green arrow), detrusor muscle and mechanical artifact are also visible. Further, the collagen signal is correlated to a brighter area in the OCT cross-section (f, green arrow). Scale bars: 250 µm.