Three-dimensional eye movement simulator extracting instantaneous eye movement rotation axes, the plane formed by rotation axes, and innervations for eye muscles

We have developed a three-dimensional eye movement simulator that simulates eye movement. The simulator allows us to extract the instantaneous eye movement rotation axes from clinical data sequences. It calculates the plane formed by rotation axes and displays it on an eyeball with rotation axes. It also extracts the innervations for eye muscles. The developed simulator is mainly programmed by a CG programming language, OpenGL. First, the simulator was applied to saccadic eye movement data in order to show the so-called Listing's plane on which all hypothetical rotation axes lie. Next, it was applied to clinical data sequences of two patients with benign paroxysmal positional vertigo (BPPV). Instantaneous actual rotation axes and innervations for eye muscle extracted from data sequences have special characteristics. These results are useful for the elucidation of the mechanism of vestibular symptoms, particularly vertigo.