A System for Study of Pediatric Visual Pathways

描述（由申请人提供）：一组儿科眼科医生和新生儿神经科医生要求提供儿科视觉通路研究系统。这些研究人员目前正在NIH支持的早产儿视网膜病变（ROP）、室周白质软化（PVL）以及斜视和弱视的研究。与遗传学合作，还计划对白化病和已知基因型受试者的视觉系统进行调查。所要求的设备用于视觉诱发电位（VEP）、眼球运动和功能磁共振成像研究，并将用于研究从眼睛到大脑的通路的功能。获得的关于视觉通路功能的信息将补充目前对眼睛和大脑结构的评估。此外，这些信息将补充已经在进行的视觉行为（心理物理）评估。在拟议的ROP和PVL研究中，正在测试的主要假设是，早产儿眼内视觉通路（ROP）或视辐射（PVL）的结构损伤显著改变了大脑视觉区域的输入。在最早的年龄，对弥散闪光刺激的VEP反应将被评估为视觉和神经发育的预测因子。在婴儿期后期，ROP和PVL受试者的纵向VEP敏锐度将是对其发育中的视觉系统的可塑性进行评估的基础数据。将在对称和不对称PVL受试者中进行视觉路径错误的VEP研究。眼动跟踪器将用于表征他们的眼球震颤，并在VEP测试期间验证注视。此外，未来的功能磁共振成像研究的设想使用模式的刺激象限，在老年人，认知完整的受试者与PVL和视野的削减，和他们的同龄人没有字段削减。大样本的足月出生婴儿，儿童和成人斜视和弱视，以及他们的健康同龄人，将有视觉诱发电位敏锐度测量的横截面设计。将对注视和随意扫视期间的眼球运动进行量化。这些信息，沿着临床数据，将为未来弱视缺陷的功能磁共振成像研究奠定基础。最后，与遗传学合作，白化病和已知酪氨酸酶基因型的家庭成员将在婴儿期使用闪光刺激和老年时使用模式刺激进行视觉通路路由的VEP研究。选择成年成员的白化病家庭将使用功能磁共振成像研究采用旋转楔刺激的Wandell和仔细控制眼睛的位置。通过这些研究作为一个整体，我们希望获得有关这些儿科疾病中控制视力及其发展的过程的新知识。

DESCRIPTION (provided by applicant): A System for Study of the Pediatric Visual Pathways is requested by a group of Pediatric Ophthalmologists and Neonatal Neurologists. These investigators currently have NIH supported studies of retinopathy of prematurity (ROP), periventricular leukomalacia (PVL), and strabismus and amblyopia. Investigations of the visual system in subjects with albinism and known genotypes are also planned in collaboration with Genetics. The equipment requested is for visual evoked potential (VEP), eye movement and fMRI studies, and will be used to investigate function of the pathways from the eye to the brain. The information gained about function of the visual pathways will complement current assessments of structure of the eye and brain. Additionally, this information will complement the behavioral (psychophysical) assessments of vision already in progress. In the proposed ROP and PVL research, the main hypothesis under test is that preterm injury to the architecture of the visual pathway in the eye (ROP) or the optic radiations (PVL) significantly alters the inputs to the visual areas of the brain. At the earliest ages, VEP responses to diffuse flash stimuli will be evaluated as predictors of visual and neurological development. Later in infancy, longitudinal VEP acuities in ROP and PVL subjects will be the basic data upon which analysis of plasticity of their developing visual systems will be evaluated. VEP studies of misrouting of the visual pathways will be conducted in subjects with symmetrical and asymmetrical PVL. The eye movement tracker will be used to characterize their nystagmus and to verify fixation during VEP testing. Furthermore, future fMRI studies are envisioned using patterned stimuli presented quadrant by quadrant, in older, cognitively intact subjects with PVL and visual field cuts, and their peers without field cuts. The large sample of term born infants, children and adults with strabismus and amblyopia, and their unaffected peers, will have VEP acuity measured in a cross-sectional design. Eye movements during fixation and voluntary saccades will be quantified. This information, along with the clinical data, will lay the foundation for future fMRI studies of the amblyopic deficit. Finally, in collaboration with Genetics, members of families with albinism and known tyrosinase genotype, will have VEP studies of visual pathway routing using flash stimuli in infancy and patterned stimuli at older ages. Selected adult members of the families with albinism will be studied using fMRI studies employing the rotating wedge stimulus of Wandell and careful control of eye position. With these studies as a whole, we expect to obtain new knowledge about the processes that govern vision and its development in these pediatric disorders.