Biomedical Engineering Letters

, Volume 9, Issue 2, pp 203–209 | Cite as

Finite element analysis of cornea deformation and curvature change during the keratoplasty suturing process

  • Jong Won Baek
  • Seong Jin ParkEmail author
Original Article


Keratoplasty, which is cornea transplant surgery, is one of the treatment methods for patients with turbidity or keratitis. Recently, keratoplasty using a surgical robot was studied to increase precision. In this study, the effect of surgical factors on the deformation and curvature of the cornea were analyzed in order to improve the accuracy of keratoplasty and derive the optimal surgical factors using finite element method (FEM). Suturing tension and depth were selected as surgical factors. An FEM model, a constitutive equation, and boundary conditions were determined using experiments and reference data. Suturing tension significantly impacted deformation and curvature change, and suturing depth affected the position of the thread-cornea contact point. Both factors have a significant impact on a focal point in the retina and the patient’s visual acuity after keratoplasty.


Cornea curvature Keratoplasty Finite element methods (FEM) Suturing 



This work was supported by the Industrial Technology Innovation Program (No. 10048358) funded by the Ministry of Trade, Industry & Energy (MI, Korea).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical Statement

This work does not contain any animal study.


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Copyright information

© Korean Society of Medical and Biological Engineering 2019

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringPohang University of Science and Technology (POSTECH)PohangKorea

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