Eye Model and Its Application - Computational Biomechanics of the Musculoskeletal System - page 280

(a) (b)

4.239 Max 3.297 2.356 1.414 0.4726

3.768 2.827 1.885 0.9434 0 Min

FIgure 21.10 (See color insert.) Retinal detachments simulated at lower (a) and higher (b) impacting
speeds by BB projectile.

greater impact speeds, the separation extends toward the posterior pole and increases in size
(Figure 21.10b).

21.3 ConCluSIonS
In this chapter, a finite element model of the human eye was introduced. The modeling method
was presented in detail, including the geometric structure of the human eye, material properties
of ocular tissues, meshing technology, and boundary conditions. ANSYS Explicit Dynamics was
employed to simulate retinal dynamic responses to projectile impact. As a robust analysis tool, the
explicit dynamic solution is ideal for simulating physical events that happen over a short time frame.
The eye model highlights modeling retinal adhesion using breakable bonded contact between the
retina and the supporting tissue. This contact, originally used to model spot welds, was then used to
simulate retinal detachment.
However, the current eye model is far from complete. The most significant limitation is lack of
experimental validation. At present, high-speed imaging for the intraocular tissues is unavailable,
making such experiments extremely difficult, if not impossible, to conduct. Therefore, other meth-
ods were used to validate the model. By comparison with a well-known eye model by Stitzel et al.
(2002), the current model was verified to simulate the dynamic response of the cornea and sclera
effectively. The model can provide details of the retinal dynamic response under blunt impact, which
enables us to understand the mechanism of traumatic retinal detachment. This work confirms that
the finite element method is an effective approach to studying eye injuries caused by blunt trauma.

aCknowledgmentS
This work was supported by the National Natural Science Foundation of China (Nos. 10925208,
11120101001, 11202017), the Beijing Natural Science Foundation (7133245), Young Scholars for the
Doctoral Program of the Ministry of Education of China (20121102120039), and the 111 Project
(No. B13003).

reFerenCeS
Bianco M., Vaiano A.S., Colella F., Coccimiglio F., Moscetti M., Palmieri V., Focosi F., Zeppilli P., Vinger P.F.,
2005. Ocular complications of boxing. British Journal of Sports Medicine 39, 70-74.