Tissue Autofluorescence is Correlated With Intima and Media Thickness in Atherosclerotic Human Aorta

This study identifies fluorescence excitation‐emission pairs correlated with atherosclerotic pathology in an ex vivo human aorta. Fluorescence spectroscopy, wide‐field fluorescence imaging, gross pathologic and histologic evaluation of ex vivo cadaveric human aorta are performed. A matrix of Pearson correlation coefficients are determined for the relationship between relevant histologic features and fluorescence intensity for 427 excitation‐emission pairs. A multiple linear regression analysis indicates that tryptophan and elastin fluorescence intensity predicts 58% of the variance in intima thickness (R‐squared = 0.588, F (2, 18) = 12.8, p = 0.0003), and 48% of the variance in media thickness (R‐squared = 0.483, F (2, 18) = 8.42, p = 0.002). Excluding lesions identified as necrotic lipid cores on histology from analysis, a combination of tyrosine, tryptophan, collagen and elastin autofluorescence predicted 86.0% of the variance in intima thickness (R‐squared = 0.8598, F (4, 13) = 19.9, p = 1.87 × 10 −5 ) and 51.8% of the variance in media thickness (R‐squared = 0.518, F (4, 13) = 3.49, p = 0.0382).