An Integrated Multiphoton Imaging Workflow for Quantitative Analysis of Aortic Tissue Microstructure.

Area of Science:

• Vascular biomechanics
• Mechanobiology
• Biomedical imaging analysis

Background:

• Aortic microstructure is crucial for vascular biomechanics and mechanobiology.
• Quantitative characterization of aortic tissue is needed for research.
• Aortic wall integrity relies on elastic layers, collagen fibers, and cells.

Purpose of the Study:

• To present a comprehensive image-analysis workflow for quantitative characterization of aortic microstructure.
• To extract quantitative descriptors of tissue microstructure from multiphoton microscopy stacks of the murine thoracic aorta.
• To provide a framework for studying aortic wall remodeling.

Main Methods:

• Multiphoton microscopy was used to acquire images of collagen, elastin, and cell nuclei.
• Image analysis included reorientation, lamellar tracing, nuclear segmentation and characterization, and 3D collagen network reconstruction.
• Quantification of lamellar thickness, interlamellar spacing, nuclear morphology, collagen fiber orientation, porosity, and fiber density was performed.

Main Results:

• The workflow successfully extracted quantitative descriptors of aortic microstructure.
• Measurements included lamellar thickness, interlamellar spacing, nuclear aspect ratio and orientation, collagen fiber straightness, amplitude, orientation distributions, porosity, and linear fiber density.
• Collagen and elastin volume fractions were computed.

Conclusions:

• The developed workflow provides a modular, robust, and integrated framework for quantitative characterization of aortic microstructure.
• This tool enables reproducible analysis of aortic wall remodeling in physiological and pathological processes.
• The workflow transforms detailed microscopy images into quantitative measurements for advancing vascular research.