Biomechanics and Modeling in Mechanobiology

, Volume 18, Issue 2, pp 319–325 | Cite as

Anvil-profiled penetrating keratoplasty: load resistance evaluation

  • Annalisa Canovetti
  • Francesca RossiEmail author
  • Michele Rossi
  • Luca Menabuoni
  • Alex Malandrini
  • Roberto Pini
  • Paolo Ferrara
Original Paper


The aim of this study was to qualitatively evaluate the biomechanical load resistance of different surgical wound configurations (mushroom, zig-zag, anvil and conventional trephination) in penetrating keratoplasty (PK) by designing a 2D and a 3D finite-element biomechanical model of the cornea. A mathematical model of the human cornea was developed, and different geometric configurations for PK were designed. The internal pressure was raised until the wound misaligned; wound prolapse then occurred. Better wound resistance was found in all the laser trephined profiles tested in comparison with the conventional straight one. The anvil profile was more resistant to the increasing internal pressure than was the mushroom or the zig-zag pattern. Thanks to its greater mechanical load resistance, the anvil profile made possible the apposition of a restricted number of sutures and early suture removal. These advantages can contribute to a faster visual recovery in patients undergoing penetrating keratoplasty.


Laser-assisted penetrating keratoplasty Cornea Surgical wound Transplanted graft resistance FEM model 



The authors wish to thank the LA ROSES experiment of the FP7 ECHORD++ project for partial support of this study and removal of the per cent signs.

Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interest.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.U.O. Oculistica Asl 4Nuovo Ospedale S. StefanoPratoItaly
  2. 2.Istituto di Fisica ApplicataConsiglio Nazionale delle RicercheSesto FiorentinoItaly
  3. 3.Istituto Nazionale di OtticaConsiglio Nazionale delle RicerchePisaItaly

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