Polarized and structured light techniques for quantitative biomedical diagnostics

Here we showcase innovative optical methods for diagnosing amyloidosis and assessing macular health using polarized light microscopy (PLM) and structured light entoptics. We present a Congo red-free PLM approach to detect amyloid fibrils in hematoxylin and eosin (H&E)-stained biopsies from diverse tissues (abdominal subcutaneous, duodenal, thyroid, breast), quantifying birefringence and amyloid density via Fourier analysis with a 520 nm laser system. Results match Congo red-stained controls without artifacts, enabling rapid, objective diagnosis of amyloid-related diseases like Alzheimer’s and cancer. Additionally, motivated by recent advances in structured light–based entoptic probes of macular health, we apply quantitative polarized light imaging to mouse retinal tissue to directly map birefringence and investigate the physical tissue interactions.