Data retrieval from archival renal biopsies using nonlinear microscopy

Thorough examination of renal biopsies may improve understanding of renal
disease. Imaging of renal biopsies with fluorescence nonlinear microscopy
(NLM) and optical clearing enables three-dimensional (3D) visualization of
pathology without microtome sectioning. Archival renal paraffin blocks
from 12 patients were deparaffinized and stained with Hoechst and Eosin
for fluorescent nuclear and cytoplasmic/stromal contrast, then optically
cleared using benzyl alcohol benzyl benzoate (BABB). NLM images of entire
biopsy fragments (thickness range 88-660 µm) were acquired using NLM with
fluorescent signals mapped to an H&E color scale. Cysts,
glomeruli, exudative lesions, and Kimmelstiel-Wilson nodules were
segmented in 3D and their volumes, diameters, and percent composition
could be obtained. The glomerular count on 3D NLM volumes was high
indicating that archival blocks could be a vast tissue resource to enable
larger-scale retrospective studies. Rapid optical clearing and NLM imaging
enables more thorough biopsy examination and is a promising technique for
analysis of archival paraffin blocks.