title: A custom image-based analysis tool for quantifying elastin and collagen micro-architecture in the wall of the human aorta from multi-photon microscopy.
abstract: The aorta possesses a micro-architecture that imparts and supports a high degree of compliance and mechanical strength. Alteration of the quantity and/or arrangement of the main load-bearing components of this micro-architecture--the elastin and collagen fibers--leads to mechanical, and hence functional, changes associated with aortic disease and aging. Therefore, in the future, the ability to rigorously characterize the wall fiber micro-architecture could provide insight into the complicated mechanisms of aortic wall remodeling in aging and disease. Elastin and collagen fibers can be observed using state-of-the-art multi-photon microscopy. Image-analysis algorithms have been effective at characterizing fibrous constructs using various microscopy modalities. The objective of this study was to develop a custom MATLAB-language automated image-based analysis tool to describe multiple parameters of elastin and collagen micro-architecture in human soft fibrous tissue samples using multi-photon microscopy images. Human aortic tissue samples were used to develop the code. The tool smooths, cleans and equalizes fiber intensities in the image before segmenting the fibers into a binary image. The binary image is cleaned and thinned to a fiber skeleton representation of the image. The developed software analyzes the fiber skeleton to obtain intersections, fiber orientation, concentration, porosity, diameter distribution, segment length and tortuosity. In the future, the developed custom image-based analysis tool can be used to describe the micro-architecture of aortic wall samples in a variety of conditions. While this work targeted the aorta, the software has the potential to describe the architecture of other fibrous materials, tube-like networks and connective tissues.
authors: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.
authors: Ryan G
authors: RG
authors: Koch
authors: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.|Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, PA, United States.|McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.
authors: Alkiviadis
authors: A
authors: Tsamis
authors: McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.|Fondazione Ri.MED, Palermo, Italy.|DICGM University of Palermo, Palermo, Italy.
authors: Antonio
authors: A
authors: D'Amore
authors: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.|Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States.|Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, PA, United States.|McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.
authors: William R
authors: WR
authors: Wagner
authors: Center for Biologic Imaging, University of Pittsburgh, Pittsburgh, PA, United States.
authors: Simon C
authors: SC
authors: Watkins
authors: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.|Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States.|Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, PA, United States.|McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.
authors: Thomas G
authors: TG
authors: Gleason
authors: Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.|Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States.|Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States.|Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, PA, United States.|McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States.
authors: David A
authors: DA
authors: Vorp
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D000465:Algorithms; D001011:Aorta / Q000033:anatomy & histology* / Q000737:chemistry*; D003238:Connective Tissue / Q000033:anatomy & histology / Q000737:chemistry; D004549:Elastin / Q000032:analysis*; D005109:Extracellular Matrix / Q000737:chemistry; D005260:Female; D024022:Fibrillar Collagens / Q000032:analysis*; D006801:Humans; D008297:Male; D008853:Microscopy; D008875:Middle Aged; D012984:Software; D016474:Weight-Bearing
chemical_list: D024022:Fibrillar Collagens; D004549:Elastin
keywords: Collagen; Elastin; Fiber orientation; Micro-architecture; Multi-photon microscopy; Quantification