Guo Hongmei, Gao Zhipeng, Chen Weiyi
Shanxi Key Laboratory of Material Strength and Structural Impact, Institute of Applied Mechanics and Biomedical Engineering, College of Mechanics, Taiyuan University of Technology, Yingze West Street 79, Taiyuan, 030024, Shanxi, China.
Biomed Eng Online. 2016 Dec 28;15(Suppl 2):137. doi: 10.1186/s12938-016-0280-0.
Pulleys have been reported as the functional origins of the rectus extraocular muscles (EOMs). However, biomechanical significance of pulleys on binocular vision has not been reported.
Three eye movement models, i.e., non-pulley model, passive-pulley model, and active-pulley model, are used to simulate the horizontal movement of the eyes from the primary position to the left direction in the range of 1°-30°. The resultant forces of six EOMs along both orthogonal directions (i.e., the x-axis and y-axis defined in this paper) in the horizontal plane are calculated using the three models.
The resultant force along the y-axis of the left eye for non-pulley model are significantly larger than that of the other two pulley models. The difference of the force, between the left eye and the right eye in non-pulley model, is larger than those in the other two pulley models along x-axis and y-axis.
The pulley models present more biomechanical advantage on the horizontally binocular vision than the non-pulley model. Combining with the previous imaging evidences of pulleys, the results show that pulley model coincides well with the real physiological conditions.
滑车已被报道为眼外直肌（EOMs）的功能起源。然而，滑车对双眼视觉的生物力学意义尚未见报道。
使用三种眼球运动模型，即无滑车模型、被动滑车模型和主动滑车模型，模拟眼球在1°-30°范围内从初始位置向左方向的水平运动。使用这三种模型计算六个眼外肌在水平面内沿两个正交方向（即本文定义的x轴和y轴）的合力。
无滑车模型中左眼沿y轴的合力显著大于其他两个滑车模型。无滑车模型中左眼和右眼之间的力差在x轴和y轴上大于其他两个滑车模型。
滑车模型在水平双眼视觉方面比无滑车模型具有更多的生物力学优势。结合先前滑车的成像证据，结果表明滑车模型与真实生理状况高度吻合。
