Physically-based modeling and simulation of extraocular muscles

Abstract

Dynamic simulation of human eye movements, with realistic physical models of extraocular muscles (EOMs), may greatly advance our understanding of the complexities of the oculomotor system and aid in treatment of visuomotor disorders. In this paper we describe the first three dimensional (3D) biomechanical model which can simulate the dynamics of ocular motility at interactive rates. We represent EOMs using "strands", which are physical primitives that can model an EOM's complex nonlinear anatomical and physiological properties. Contact between the EOMs, the globe, and orbital structures can be explicitly modeled.Several studies were performed to assess the validity and utility of the model. EOM deformation during smooth pursuit was simulated and compared with published experimental data; the model reproduces qualitative features of the observed non-uniformity. The model is able to reproduce realistic saccadic trajectories when the lateral rectus muscle was driven by published measurements of abducens neuron discharge. Finally, acute superior oblique palsy, a pathological condition, was simulated to further evaluate the system behavior; the predicted deviation patterns agree qualitatively with experimental observations. This example also demonstrates potential clinical applications of such a model.

On geodesics of the rotation group SO(3)

“…The human eye is widely modeled as a rigid body which is free to rotate about a point O which is fixed in the head and a wide range of models for the eye appear in the literature (see, e.g., [2,8,33,43]) with the state-of-the-art dynamic model appearing in the recent work of Wei et al [43]. The model in [43] is unique in its modeling of the complex system of six muscle groups acting on the eye.…”

“…The model in [43] is unique in its modeling of the complex system of six muscle groups acting on the eye. Among other issues these models are designed to help further ongoing research on the neuromuscular scheme which controls vision.…”

“…(b) The quaternion components (q 0 , q 2 , q 3 ) corresponding to the periodic motions. The Class II and Class III solutions were obtained by integrating (43). For the cases shown: H = 1, λ 1,2,3 = 1, ψ(0) = 0, and (i)…”

“…These models started in the 1970s with the work of Robinson [25,35] and has lead to models where the muscles are modeled with improved fidelity, such as [33,43], models for a robotic eye by Cannata and Maggiali [2] and a rigid body model with generalized control torques by Ghosh et al [7,8,31]. The resulting models can be combined with control strategies to gain a deeper understanding of how the brain controls the ocular system and enables vision.…”

Simulation of Active Eye Motion Using Finite Element Modelling

“…"Strands" are used by Wei et al 2010 as a new modelling approach for eye. By using this method, more emphasis is devoted on muscles model by more accurate mass distribution modelling.…”