A System for Study of Pediatric Visual Pathways

描述(申请人提供)：一组儿科眼科医生和新生儿神经科医生要求建立一套儿科视觉通路研究系统。这些研究人员目前有NIH支持的早产儿视网膜病变(ROP)、脑室周围白质软化(PVL)以及斜视和弱视的研究。与Genetics合作，还计划对患有白化病和已知基因型别的受试者的视觉系统进行调查。所需设备用于视觉诱发电位(VEP)、眼球运动和功能磁共振研究，并将用于研究从眼睛到大脑的通路的功能。获得的有关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力行为(心理物理)评估。在拟议的ROP和PVL研究中，接受测试的主要假设是，眼内视觉通路(ROP)或光辐射(PVL)的结构早产损伤显著改变了大脑视觉区域的输入。在最小的年龄，VEP对漫反射闪光刺激的反应将被评估为视觉和神经发育的预测指标。在婴儿期后期，ROP和PVL受试者的纵向VEP敏感度将成为评估其视觉系统发育可塑性的基础数据。将在对称性和非对称性PVL受试者中进行视觉通路错位的VEP研究。眼动跟踪器将被用来描述他们的眼球震颤，并在VEP测试期间验证他们的注视。此外，在有PVL和视野切割的老年认知完整受试者以及没有视野切割的同龄人中，未来的fMRI研究将使用逐个象限呈现的图案化刺激。对足月出生的婴儿、患有斜视和弱视的儿童和成人以及他们的未受影响的同龄人进行大样本的VEP视力测量，采用横断面设计。注视和自愿扫视过程中的眼球运动将被量化。这一信息与临床数据一起，将为未来弱视缺陷的功能磁共振研究奠定基础。最后，与Genetics合作，患有白化病和已知酪氨酸酶基因的家庭成员将使用婴儿时期的闪光刺激和老年时的图案刺激进行视觉通路路径的视觉诱发电位研究。白化病家庭中选定的成年成员将使用Wandell旋转楔形刺激和仔细控制眼睛位置的功能磁共振研究进行研究。作为一个整体，我们希望通过这些研究，获得有关控制视力及其在这些儿科疾病中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.