Hypothesis: Thin-sheet laser imaging microscopy (TSLIM) optical sectioning can be used to assess temporal bone soft tissue morphology before celloidin sectioning.
Background: Traditional human temporal bone (TB) celloidin embedding and sectioning is a lengthy and involved process. Although bone morphology can be assessed with microCT before traditional histology, soft tissue structures are difficult to resolve until after celloidin sectioning. A potential solution is TSLIM, a high-resolution, nondestructive optical sectioning technique first developed to image bone and soft tissue in animal cochleae.
Methods: Two temporal bones from 1 individual were used to evaluate TSLIM’s capacity to image human temporal bones (bone and soft tissue) before traditional histology. The right TB was trimmed to the cochlea, prepared for and imaged with TSLIM, then processed for celloidin sectioning. The left TB, serving as a control, was directly prepared for traditional celloidin sectioning.
Results: TSLIM imaging of the right TB showed adequate resolution of all major tissue structures but barely resolved cells. Celloidin sections produced from the TSLIM-imaged right TB were equivalent in cytologic detail to those from the traditionally prepared left TB. TSLIM 3-dimensional (3D) reconstructions were superior to those obtained from celloidin sections because TSLIM produced many more sections that were without mechanical sectioning artifacts or alignment issues.
Conclusion: TSLIM processing disturbs neither gross nor detailed morphology and integrates well with celloidin histology, making it an ideal method to image soft tissue before celloidin sectioning.
*Department of Otolaryngology, University of Minnesota, Minneapolis, Minnesota; and †Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, U.S.A.
Address correspondence and reprint requests to Shane Johnson, B.S., Department of Otolaryngology, 2001 Sixth St. SE, Minneapolis, MN 55455; E-mail: firstname.lastname@example.org
S. B. J. performed TSLIM processing and imaging, compiled the results, prepared the figures, and wrote the manuscript. S. C. provided input on temporal bone anatomy and assisted with trimming the bone and writing the manuscript. J. T. O. performed celloidin histology and imaging and helped write the manuscript. P. A. S. helped compile the results, prepare the figures, and write the manuscript.
Funding for TSLIM was provided by the NIDCD (RO1DC007588-04) and an ARRA supplement (RO1DC007588-03S1). Human temporal bone processing was funded by the NIDCD (U24DC011968-01), the Capita Foundation, and the Lions Hearing Foundation.
The authors disclose no conflicts of interest.