Fourier analysis of collagen bundle orientation in myocardial infarction scars

AbstractCollagen bundle orientation (CBO) in myocardial infarct scars plays a major role in scar mechanics and complications after infarction. We aim to compare four histopathological methods for CBO measurement in myocardial scarring. Myocardial infarction was induced in 21 pigs by balloon coronary occlusion. Scar samples were obtained at 4  weeks, stained with Masson’s trichrome, Picrosirius red, and Hematoxylin–Eosin (H&E), and photographed using light, polarized light microscopy, and confocal microscopy, respectively. Masson ’s trichrome images were also optimized to remove non-collagenous structures. Two observers measured CBO by means of a semi-automated, Fourier analysis protocol. Interrater reliability and comparability between techniques were studied by the intraclass correlation coefficient (ICC) and Bland–Alt man (B&A) plots and limits of agreement. Fourier analysis showed an almost perfect interrater reliability for each technique (ICC  ≥ 0.95,p <  0.001 in all cases). CBO showed more randomly oriented values in Masson’s trichrome and worse comparability with other techniques (ICC vs. Picrosirius red: 0.79 [0.47–0.91],p = 0.001; vs. H&E-confocal: 0.70 [0.26 –0.88],p = 0.005). However, optimized Masson’s trichrome showed almost perfect agreement with Picrosirius red (ICC 0.84 [0.6–0.94],p <  0.001) and H&E-confocal (ICC 0.81 [0.54 –0.92],p <  0.001), as well as these latter techniques between e...
Source: Histochemistry and Cell Biology - Category: Biomedical Science Source Type: research