The presented study focuses on the application of scanning laser optical tomography (SLOT) for non-destructive
visualization of anatomical structures inside the human cochlea ex vivo. SLOT is a laser-based highly efficient
microscopy technique, which allows for tomographic imaging of the internal structure of transparent large-scale
specimens (up to 1 cm3). Thus, in the field of otology this technique is best convenient for an ex vivo study of the inner
ear anatomy. For this purpose, the preparation before imaging comprises mechanically assisted decalcification,
dehydration as well as optical clearing of the cochlea samples. Here, we demonstrate results of SLOT visualizing hard
and soft tissue structures of the human cochlea with an optical resolution in the micrometer range using absorption and
autofluorescence as contrast mechanisms.
Furthermore, we compare our results with the method of X-ray micro tomography (micro-CT, μCT) as clinical gold
standard which is based only on absorption. In general, SLOT can provide the advantage of covering all contrast
mechanisms known from other light microscopy techniques, such as fluorescence or scattering. For this reason, a
protocol for antibody staining has been developed, which additionally enables selective mapping of cellular structures
within the cochlea. Thus, we present results of SLOT imaging rodent cochleae showing specific anatomical structures
such as hair cells and neurofilament via fluorescence. In conclusion, the presented study has shown that SLOT is an
ideally suited tool in the field of otology for in toto visualization of the inner ear microstructure.