CmyoSize: An ImageJ macro for automated analysis of cardiomyocyte size in images of routine histology staining

Background: Cardiomyocyte size histomorphometry is widely required in myocardial remodeling research, but it relies on subjective, time-consuming manual tracing. We aimed to present the CmyoSize, a Fiji/ImageJ macro that reproducibly measures the transnuclear cross-sectional size of cardiomyocytes in multiple H&E images. Methods: CmyoSize output per image are: mean cross-sectional area (CSA), CSA's local standard deviation (LSD), mean width, and width's LSD. CmyoSize was validated against measurements of an expert examiner, using myocardium micrographs (40 0-fold magnification) from rats treated with hyperbaric oxygen (HBO), streptozotocin (STZ), as well as control rats (five images/heart, five rats/group). Results: CmyoSize achieved high cardiomyocyte detection precision (95.17 +/- 1.11%) and it analyzed each image at least 30-times faster than expert examiner (8.44 +/- 0.17 s vs. 266.70 +/- 25.15 s). Bland-Altman analyses showed no meaningful bias ( +/- 95% confidence interval) between both methods: mean CSA = 1.88 +/- 6.83 mu m2, CSA's LSD = -4.55 +/- 5.07 mu m2; mean width = -0.02 +/- 0.22 mu m; width's LSD = -0.16 +/- 0.17 mu m. Pearson's r ranged from 0.85 to 0.94 (P < 0.0001). CmyoSize revealed homogenous cardiomyocyte hypertrophy in HBO-treated animals and STZ-induced heterogeneous hypertrophy. Conclusion: Fully automated, standardized cardiomyocyte size quantification in H&E images using CmyoSize is feasible, accurate, and time-efficient. (c) 2022 Elsevier GmbH. All rights reserved.

Automated summary

The study presents a macro called CmyoSize, which accurately measures the transnuclear cross-sectional size of cardiomyocytes in H&E images. It is a fully automated and standardized method that achieves high precision and is much faster than manual tracing. The results show that CmyoSize is feasible, accurate, and time-efficient for cardiomyocyte size quantification.