Nonlinear fourth-order elastic characterization of the cornea using torsional wave elastography

• DOI: 10.1007/s13246-023-01314-8
• Publication Date: 2023-08-29T08:06:42Z
• Authors: Antonio Callejas; Inas Faris; Jorge Torres; Guillermo Rus
• Keywords: Fourth-order elastic properties; Cornea; Elasticity Imaging Techniques; Torsional wave elastography (TWE); Scientific Paper

Abstract Measuring the mechanical nonlinear properties of cornea remains challenging due to lack consensus in methodology and models that effectively predict its behaviour. This study proposed developing a procedure reconstruct fourth-order elastic based on mathematical model derived from theory Hamilton et al. using torsional wave elastography (TWE) technique. In order validate diagnostic capability simulated pathological conditions, two different groups were studied, non-treated samples (n=7), ammonium hydroxide ( $$NH_4OH$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>N</mml:mi> <mml:msub> <mml:mi>H</mml:mi> <mml:mn>4</mml:mn> </mml:msub> <mml:mi>O</mml:mi> </mml:mrow> </mml:math> ) treated (n=7). All measured in-plane by device increasing IOP 5 25 mmHg with steps. The results show variation shear speed IOP, higher values for IOPs. Moreover, control group than those group. also revealed significant differences between Lamé parameter $$\mu$$ <mml:mi>μ</mml:mi> (25.9–6.52 kPa), third-order constant A (215.09–44.85 D (523.5–129.63 p-values 0.010, 0.024, 0.032, respectively. These findings demonstrate can distinguish healthy damaged corneas, making it promising technique detecting diseases associated alteration, such as corneal burns, glaucoma, or ocular hypertension.