BINOCULAR COORDINATION OF EYE MOVEMENTS

描述(申请人提供)：必须在水平、垂直和扭转平面上保持双眼对齐，以确保双眼感觉融合。正常的发育确保了双眼在注视时对齐，在眼睛运动时双眼协调。不幸的是，发育过程中异常的视觉体验通常会导致眼睛不对准(斜视)。事实上，各种研究都报告了斜视的发病率约占婴儿人口的2%-5%。来自我们实验室的斜视人类和斜视猴子的数据表明，眼睛不对准伴随着缺乏共轭眼球运动。虽然斜视最常与水平错位有关，但通常也会观察到水平、垂直和扭转的综合错位。除了静态的水平、垂直和扭转错位，主要眼球运动平面之间似乎存在大量的动态串扰。在临床文献中，这种明显的跨轴相互作用通常被描述为斜视的‘A’和‘V’型。不幸的是，人们缺乏对这些跨轴运动的神经或力学基础的了解，缺乏对水平、垂直或扭转眼球运动的神经控制的推定关系或缺乏，以及与斜视病因的关系。相互竞争的假说包括眼外肌滑轮的静态错位，眼外肌和肌肉滑轮的侧滑，眼球运动的扭转控制出错导致明显的肌肉功能障碍，最后只是原因不明的个别眼外肌反应过度/反应不足。我们研究的目的是阐明跨轴运动的静态和动态特性，并研究其在感觉性斜视动物中的来源。我们的方法将包括眼外肌的结构成像以确定肌肉滑轮的作用；行为实验以检查扭转的控制和Listing定律；神经生理学实验以检查运动和运动前结构在大脑中的作用；以及眼外肌肉的生物力学建模以模拟实验数据。本研究的完成将有助于对某些类型斜视的认识和治疗。

DESCRIPTION (provided by applicant): Binocular alignment must be maintained in the horizontal, vertical and torsional planes to ensure binocular sensory fusion. Normal development ensures binocular alignment during fixation and binocular coordination during eye movements. Unfortunately, abnormal visual experience during development usually leads to ocular misalignment (strabismus). In fact, various studies have reported the incidence of strabismus to be about 2-5% of the infant population. Data from strabismic humans and from strabismic monkeys in our laboratory have shown that ocular misalignment is accompanied by a lack of conjugate eye movements. Though strabismus is most often associated with a horizontal misalignment, often a combined horizontal, vertical and torsional misalignment is observed. Along with the static horizontal, vertical and torsional misalignment, there appears to be substantial dynamic cross-talk between the principal eye movement planes. In the clinical literature these apparent cross-axis interactions are usually described as 'A' and 'V' patterns of strabismus. Unfortunately, there is a lack of understanding of the neural or mechanical bases for these cross-axis movements, the putative relationship or lack thereof to the neural control of horizontal, vertical or torsional eye movements and the relationship to the etiology of the strabismus. Competing hypotheses include static malpositioning of extraocular muscle pulleys, sideslip of extraocular muscles and muscle pulleys, torsional control of eye movements gone awry leading to apparent muscle dysfunction and finally simply unexplained overaction/underaction of individual extraocular muscles. The goal of our studies is to clarify static and dynamic properties of cross-axis movements and examine its source in animals with a sensory induced strabismus. Our approach will include structural imaging of extraocular muscle to determine role of muscle pulleys; behavioral experiments to examine control of torsion and Listing's laws; neurophysiological experiments to examine the role of motor and pre-motor structures in the brain and biomechanical modeling of extraocular musculature to simulate experimental data. Completion of our studies will be of benefit to the understanding and treatment of certain types of strabismus.