Characterization of aortic valve stenosis by mathematical modelling of the reflectance spectroscopy

Abstract

Background: The stenosis of the aortic valve is a consequence of an increased thickness and disorganization of the collagen fibre network and extracellular matrix, plus the deposits of calcification in the layers of the valve. These characteristics are known to affect the diffuse spectral reflectance of the tissue.

Objective: The main focus of this work is to propose a model for the aortic valve reflectance whose parameters can be employed as features capable of discriminating distinct levels of tissue thickness and disorganization.

Methods: The data obtained from aortic valve reflectance show a S-type curve. Therefore, the modeling hypothesis is that the aortic valve stenosis generates a sigmoidal behavior at the reflectance spectroscopy. The mathematical modeling was obtained by a sigmoidal approaching and Euler methodology applied.

Results: The results show the successful application of the model in the investigation of heart valve tissues with distinct characteristics.

Conclusion: The solutions of this equation define parameters that can be interpreted quantitatively helping to discriminate the stenosis process in aortic valve predictable for different cases proposed in this study.