Nondestructive Evaluation of Mechanical and Histological Properties of the Human Aorta With Near-Infrared Spectroscopy

Jaakko K Sarin; Miika Kiema; Emma-Sofia Luoto; Annastiina Husso; Marja Hedman; Johanna P Laakkonen; Jari Torniainen

doi:10.1016/j.jss.2023.01.016

Nondestructive Evaluation of Mechanical and Histological Properties of the Human Aorta With Near-Infrared Spectroscopy

J Surg Res. 2023 Jul:287:82-89. doi: 10.1016/j.jss.2023.01.016. Epub 2023 Mar 2.

Authors

Jaakko K Sarin¹, Miika Kiema², Emma-Sofia Luoto², Annastiina Husso³, Marja Hedman⁴, Johanna P Laakkonen², Jari Torniainen⁵

Affiliations

¹ Department of Medical Physics, Medical Imaging Center, Tampere University Hospital, Tampere, Finland; Department of Radiology, Tampere University Hospital, Tampere, Finland; Department of Technical Physics, University of Eastern Finland, Kuopio, Finland. Electronic address: jaakko.sarin@pirha.fi.
² A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.
³ Department of Cardiothoracic Surgery, Kuopio University Hospital, Kuopio, Finland.
⁴ Department of Cardiothoracic Surgery, Kuopio University Hospital, Kuopio, Finland; Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland; Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.
⁵ Department of Technical Physics, University of Eastern Finland, Kuopio, Finland; School of Information Technology & Electrical Engineering, The University of Queensland, Brisbane, Australia.

PMID: 36870305
DOI: 10.1016/j.jss.2023.01.016

Abstract

Introduction: Ascending aortic dilatation is a well-known risk factor for aortic rupture. Indications for aortic replacement in its dilatation concomitant to other open-heart surgery exist; however, cut-off values based solely on aortic diameter may fail to identify patients with weakened aortic tissue. We introduce near-infrared spectroscopy (NIRS) as a diagnostic tool to nondestructively evaluate the structural and compositional properties of the human ascending aorta during open-heart surgeries. During open-heart surgery, NIRS could provide information regarding tissue viability in situ and thus contribute to the decision of optimal surgical repair.

Materials and methods: Samples were collected from patients with ascending aortic aneurysm (n = 23) undergoing elective aortic reconstruction surgery and from healthy subjects (n = 4). The samples were subjected to spectroscopic measurements, biomechanical testing, and histological analysis. The relationship between the near-infrared spectra and biomechanical and histological properties was investigated by adapting partial least squares regression.

Results: Moderate prediction performance was achieved with biomechanical properties (r = 0.681, normalized root-mean-square error of cross-validation = 17.9%) and histological properties (r = 0.602, normalized root-mean-square error of cross-validation = 22.2%). Especially the performance with parameters describing the aorta's ultimate strength, for example, failure strain (r = 0.658), and elasticity (phase difference, r = 0.875) were promising and could, therefore, provide quantitative information on the rupture sensitivity of the aorta. For the estimation of histological properties, the results with α-smooth muscle actin (r = 0.581), elastin density (r = 0.973), mucoid extracellular matrix accumulation(r = 0.708), and media thickness (r = 0.866) were promising.

Conclusions: NIRS could be a potential technique for in situ evaluation of biomechanical and histological properties of human aorta and therefore useful in patient-specific treatment planning.

Keywords: Aortic aneurysm; Biomechanics; Histology; Multivariate modeling; Spectroscopy.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aorta / physiology
Aortic Aneurysm* / surgery
Aortic Diseases*
Biomechanical Phenomena / physiology
Elasticity
Humans
Spectroscopy, Near-Infrared