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一个用于儿童视觉通路研究的系统。这些研究者目前有NIH支持的早产儿视网膜病变（ROP）、脑室周围白质软化（PVL）、斜视和弱视的研究。白化病和已知基因型受试者的视觉系统调查也计划与遗传学合作。所要求的设备是用于视觉诱发电位（VEP）、眼动和fMRI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，这些信息将补充正在进行的视觉行为（心理物理）评估。在提出的ROP和PVL研究中，主要的假设是，早产儿对眼睛视觉通路结构（ROP）或视光辐射（PVL）的损伤显著改变了大脑视觉区域的输入。在最早的年龄，VEP对漫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敏度值将成为评估其视觉系统发育可塑性分析的基础数据。将在对称和不对称PVL的受试者中进行视觉路径错误的VEP研究。眼球运动追踪器将用于描述他们的眼球震颤，并在VEP测试中验证固定。此外，未来的fMRI研究设想使用象限象限的模式刺激，在老年，认知完整的受试者中，有PVL和视野切割，以及没有视野切割的同龄人中。对足月出生的婴儿、患有斜视和弱视的儿童和成人，以及他们未受影响的同龄人，将采用横断面设计测量VEP灵敏度。注视时的眼球运动和自发性扫视将被量化。这一信息，连同临床数据，将为未来弱视缺陷的fMRI研究奠定基础。最后，在与遗传学的合作下，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图案刺激进行视觉通路路径的VEP研究。选择白化病家庭的成年成员将使用功能磁共振成像研究，使用旋转的楔形刺激Wandell和仔细控制眼睛的位置。随着这些研究作为一个整体，我们期望在这些儿科疾病中获得关于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.