0
Technical Brief

Appropriate Objective Functions for Quantifying Iris Mechanical Properties Using Inverse Finite Element Modeling

[+] Author and Article Information
Anup Pant

Department of Biomedical Engineering, The University of Akron, Akron, Ohio 44325
adp63@zips.uakron.edu

Syril Dorairaj

Department of Ophthalmology, Mayo Clinic, Jacksonville, Florida 32224
dorairaj.syril@mayo.edu

Rouzbeh Amini

Assistant Professor, Member of ASME, Department of Biomedical Engineering, The University of Akron, Akron, Ohio 44325
ramini@uakron.edu

1Corresponding author.

ASME doi:10.1115/1.4039679 History: Received July 07, 2017; Revised February 27, 2018

Abstract

Quantifying the mechanical properties of the iris is important, as it provides insight into the pathophysiology of glaucoma. Recent ex-vivo studies have shown that the mechanical properties of the iris are different in glaucomatous eyes as compared to normal ones. Notwithstanding the importance of the ex-vivo studies, such measurements are severely limited for diagnosis and preclude development of treatment strategies. With the advent of detailed imaging modalities, it is possible to determine the in-vivo mechanical properties using inverse finite element modeling. An inverse modeling approach requires an appropriate objective function for reliable estimation of parameters. In the case of the iris, numerous measurements such as iris chord length and iris concavity are made routinely in clinical practice. In this study, we have evaluated five different objective functions chosen based on the iris biometrics (in the presence and absence of clinical measurement errors) to determine the appropriate criterion for inverse modeling. Our results showed that in the absence of experimental measurement error, a combination of iris chord length and concavity can be used as the objective function. However, with the addition of measurement errors, the objective functions that employ a large number of local displacement values provide more reliable outcomes.

Copyright (c) 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In