Purchase this article with an account.
Kanno Okamura, Eiichi Uchio; Finite element analysis of air gun impact on post-keratoplasty eye. Invest. Ophthalmol. Vis. Sci. 2020;61(7):2914.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Due to the mechanical vulnerability of eyes that underwent penetrating keratoplasty (PKP), it is clinically important to evaluate the possibility of corneal wound dehiscense by blunt impact. We have previously developed a simulation model resembling a human eye based on the information obtained from cadaver eyes and applied this three-dimensional finite element analysis (FEA) to determine the physical and mechanical response of an air gun impact at various velocities on post-PKP eye.
Simulations in a model human eye were performed with a computer using a FEA program created by Nihon, ESI Group. The air gun was set to impact the eye at three different velocities on straight or 12° up gaze positions with the addition of keratoplasty suture strength variation in 30%, 50% and 100% of normal corneal strength.
In contrast to little damage in case of 100% strength, in cases of lower strength of straight gaze positions, wound rupture seemed to happen in early phase (0.04 – 0.06 msec) of impact in low speeds, while regional break was observed at 0.14 msec after the impact in high speed impact (75 m/sec). In contrast, wound damage was observed in the area of lower quadrant of suture zone and sclera in 12° up gaze cases. Wound damage was observed after 0.08 msec after the impact threatening to corneoscleral laceration and its area was larger in middle impacting velocity (60 m/sec) simulations than that in the cases of low impacting velocity, and larger damaged area was observed in high impacting velocity cases and corneoclereal laceration was inevitable.
These results suggest that corneal damage around suture area is most susceptible to be affected especially in straight gaze impact by air gun and special precaution measure should be considered in patients who underwent PKP. FEA using human eyeball model might be a useful method to analyze and predict the mechanical feature of eyes that underwent keratoplasty.
This is a 2020 ARVO Annual Meeting abstract.
This PDF is available to Subscribers Only