婴幼儿弱视的筛查和早期诊断

弱视检测对于保证视觉发育正常,避免视觉功能永久性下降具有重要意义。用传统的视力筛查对婴幼儿可能很困难,因为在检查过程中婴幼儿很难合作。目前弱视的诊断及治疗大多是在学龄期的儿童,如何早期发现及诊断学龄前,尤其是幼儿期的弱视显得尤为重要。本文就弱视的视觉筛查、视觉诱发电位检测、弱视的危险因素、如何做到早期诊断弱视及未来趋势作一概述。     

学龄前儿童弱视的早期筛查

弱视是一种由视觉敏感期异常视觉经验引起的以神经系统发育异常为主、无眼部器质性病变的疾病。视力检查是儿童弱视筛查与诊断中的重要组成部分,但对于不能言语表达的低龄儿童,视力检查受到限制。而屈光不正和屈光参差是引起弱视的最常见危险因素,近年来,对弱视的早期筛查不断延伸至对弱视相关危险因素的早期筛查,针对屈光状态的筛查方法与技术也在不断更新发展。本文试对视力检查方法和屈光性质筛查方法进行综述。     

摄影验光技术在婴幼儿弱视相关因素筛查中的应用进展

弱视相关因素的早期有效筛查是减少弱视发病率,提高弱视疗效的关键。眼科工作者已经将照相技术应用在婴幼儿视力筛查中并且不断探讨更加适用于婴幼儿特点的方法,本文主要综述目前国内外该技术的应用情况及前景。     

婴幼儿的视力发育及其检查方法

婴儿从出生睁开眼的一霎那间,其视力的发育就已经开始,所以了解婴幼儿的视力发育是越早越好。本文就婴幼儿的视觉发育及其检查方法做一综述。一、视力的发育及关键期对学龄期儿童的视力普查可以追溯到上个世纪, 20世纪50年代开始了针对弱视而进行的学龄期儿童的视力普查;到了60年代,有动物实验证实大脑皮层的可塑期只局限于生命的早期,于是视力普查重点放     

学龄前儿童弱视筛查

弱视是儿童视觉损害的常见原因之一，也是成年人单眼视觉损害的主要原因，严重影响个人生活质量和加重社会负担。研究表明弱视筛查有利于预防弱视发生，越早发现疗效越好。一些发达国家已普遍开展学龄前儿童弱视筛查，筛查方法较多，摄影验光法对于3岁以下幼儿价值较大，3岁以上幼儿用传统方法更可靠。统一筛查标准将有助于对各种筛查方法进行评价。     

婴幼儿疑难视觉异常的早期检查和治疗

人的视觉发育从胚胎开始至出生后婴幼儿期 ,是一生中至关重要的发育时期 ,如果在这一时期的某阶段发生了视觉发育障碍 ,且未能及时发现和抓紧时机处理 ,就会导致视觉缺陷 ,例如弱视 ,双眼单视功能缺损 ,严重者导致终生视觉残疾 ,即低视力或盲。早产儿视网膜病变 ,单眼高度近视及弱视 ,先天性白内障等都是临床上较为多见和疑难的婴幼儿视觉异常的眼病。早产儿由于缺乏足够的胚胎发育过程或低出生体重 ( <1 50 0 g)而致玻璃体视网膜病变 ,主要表现为视网膜血管增殖性病变 ,称早产儿视网膜病变 (retinopathyof prematurity ,ROP)。根据病变范…     

弱视儿童的视知觉研究进展

弱视是较为常见的眼病,是视觉发育敏感期异常视觉经验所导致的以空间视力损害为特征的一组视力不良综合征。本文通过整理以往研究,对弱视儿童视知觉的研究作了综述,主要包括空间特征对弱视儿童形状知觉的影响、空间方位对弱视儿童立体视觉的影响、空间目标对弱视儿童视知觉的影响、不同的目标运动特征对弱视儿童视觉运动觉的影响,以及弱视儿童视知觉相关的脑机制研究。[眼科新进展,2012,32(9):893-898]     

成年人弱视的认识与研究进展

成年人弱视是通常弱视概念的延伸,视神经可塑性的研究证明了成年人弱视治疗的可能性.与儿童弱视相比,成年人弱视有其群体和生理发育的特殊性,本文概述了近几年国内外相关文献报道,阐述了成年人弱视的相关治疗方法及其特殊性,提示进一步研究和探索成年人弱视的治疗将对以往视觉发育及视觉可塑性的理论提出新的挑战.     

弱视的基础与临床的研究进展

弱视是视觉发育敏感期异常视觉经验所导致的以空间视力损害为特征的一组视力不良综合征。据统计：弱视在人群中的发病率为2％-4％,大约40％～60％的儿童斜视、屈光参差因治疗不及时发展成弱视。近年来，随着分子生物学、神经科学、影像学和心理物理学的发展，弱视的基础和临床研究取得了明显的进步，笔者就近年来弱视的研究进展进行综述。     

弱视与微扫视

弱视是儿童视觉发育过程中常见的空间视觉发育混乱的眼病,是危害青少年儿童视觉发育的眼病之一,常发生在视觉发育尚未成熟的幼儿期。表现为异常形式的视力及双眼视功能,这种不正常的视觉经验可以由儿童时期的斜视、高度屈光不正、屈光参差和形觉剥夺等原因造成。弱视患者的最佳矫正视力低于正常,对比敏感度降低,立体视缺陷甚至缺失,出现拥挤现象。此外,弱视还对眼球运动系统产生影响。近年来对微扫视的研究成为眼科的热点研究问题,通过文献回顾,可以了解微扫视的研究进展以及微扫视技术在弱视方面的应用。     

The effects of preterm birth on visual development

Children born very preterm are at a greater risk of abnormal visual and neurological development when compared to children born at full term. Preterm birth is associated with retinopathy of prematurity (a proliferative retinal vascular disease) and can also affect the development of brain structures associated with post‐retinal processing of visual information. Visual deficits common in children born preterm, such as reduced visual acuity, strabismus, abnormal stereopsis and refractive error, are likely to be detected through childhood vision screening programs, ophthalmological follow‐up or optometric care. However, routine screening may not detect other vision problems, such as reduced visual fields, impaired contrast sensitivity and deficits in cortical visual processing, that may occur in children born preterm. For example, visual functions associated with the dorsal visual processing stream, such as global motion perception and visuomotor integration, may be impaired by preterm birth. These impairments can continue into adolescence and adulthood and may contribute to the difficulties in learning (particularly reading and mathematics), attention, behaviour and cognition that some children born preterm experience. Improvements in understanding the mechanisms by which preterm birth affects vision will inform future screening and interventions for children born preterm.     

Visual acuity in human infants: a review and comparison of behavioral and electrophysiological studies.

Three techniques—optokinetic nystagmus (OKN), preferential looking (PL), and the visually evoked potential (VEP)—have been used to assess visual acuity in infants between birth and 6 months of age. All three techniques indicate that the visual acuity of infants increases during the first 6 months postnatal. The accumulating evidence strongly suggests that all three techniques give meaningful and reliable—if somewhat different—estimates of visual acuity in infants, and that variants of these techniques will eventually be useful for the assessment of infant vision in clinical settings.     

Development of object vision in infants with permanent cortical visual impairment.

We examined 30 infants in whom cortical visual impairment was diagnosed during their first year of life to ascertain prognostic factors for the development of object vision, defined as the ability to recognize faces or hand-held toys. All patients were followed up for a minimum of 12 months. The most common causes of cortical visual impairment in the 30 infants were hydrocephalus in nine infants (30.0%), birth asphyxia or neonatal hypoxia in eight infants (26.7%), intracranial hemorrhage with or without hydrocephalus in seven infants (23.3%), and meningitis in five infants (16.7%). Lack of development of object vision was associated only with hypoxia (P = .013). Findings on ophthalmic examination, an abnormality in the visual pathway on computed tomographic or magnetic resonance scan, and seizures, hydrocephalus, intracranial hemorrhage, meningitis, cerebral palsy, developmental delay, prematurity, microcephaly, and hearing deficit, did not appear to be risk factors for the lack of development of object vision.     

Visual acuity screening of infants and young children with the acuity card procedure

A new acuity test for infants and young children between 1 and 36 months of age is described. The test was used to evaluate the acuities of 66 infants and young children during a one-day vision screening. At least one estimate of visual acuity was obtained from 63 of the 66 children. Fifty-two of the children completed two monocular acuity tests (or two monocular tests plus a binocular test). The average total test time for these 52 children was less than 15 minutes. Results indicate that the acuity card procedure can be used as a complement to standard optometric tests for large-scale screening of infants and young children.     

早产儿与足月儿屈光发育特点的比较

目的比较0～2岁早产儿与足月儿屈光发育特点,为早产儿早期开展视力筛查工作提供理论依据。方法选取2009年12月至2010年12月在我院健康体检的早产儿264例(528眼),按矫正月龄分为6月龄、9月龄、12月龄、18月龄、24月龄共5组,各年龄段同期随机选取50名(100眼)足月儿作为对照组,使用Suresight视力筛查仪测量双眼屈光度,分析早产儿与足月儿屈光状态,描绘屈光发育曲线。结果早产儿与足月儿在0～2岁期间屈光发育曲线走势基本一致,球镜值和柱镜值均随年龄增长而呈下降趋势。屈光状态以远视为主者,早产儿412眼,占78.0%,足月儿428眼,占85.6%;近视发生率早产儿高达2.7%(14/528),足月儿仅为0.8%(4/500);混合散光发生率早产儿为17.0%(90/528),足月儿为10.6%(53/500),差异均有统计学意义(均为P<0.05)。结论早产儿存在近视和散光的高风险。对早产儿应早期开展眼保健工作,定期连续进行视力筛查,及时发现屈光状态异常并矫治。     

Preschool vision screening for amblyopia and strabismus. Programs, methods, guidelines, 1983

Amblyopia and strabismus, which afflict at least 5% of children, require treatment early in life for best visual results. At present, many such children are treated late or not at all. Mass screening at preschool age, and perhaps ultimately of infants, appears the only viable solution to this problem. To ascertain the present status of preschool screening in the United States, on-site visits, mail questionnaires and telephone interviews were used to study existing preschool vision screening programs at the federal, state and private organization levels. We estimate that, at most, 21% of preschool children receive any form of vision screening. Only two states, Michigan and Minnesota, have legislated requirements for such screening. Several organizations have attempted to establish screening guidelines, with suggestions of specific test and referral criteria. These guidelines are reviewed. The guidelines are of particular interest because screening programs following them typically indicate far lower prevalence rates than most studies indicate actually exist, suggesting that the guidelines result in underreferrals. In order to assess this matter, vision screening methods appropriate for preschoolers or infants, based on current evidence, are reviewed. Stereoscopic testing, utilizing a random dot stereogram format, appears the best instrument available for amblyopia and strabismus screening, but large scale comparative studies of the different test methods are needed to arrive at a final determination. Suggestions are made for the physician interested in initiating preschool vision screening programs.     

A review of paediatric vision screening protocols and guidelines

Vision screening plays an important role in the early detection of children who have or probably are predisposed to have specific visual problems. The validity and reliability of the screening batteries in relation to the age group to be screened, and the person administering the test as well as the referral and follow-up criteria contribute to the overall outcome of the vision screening. Despite the long history of vision screening and significant improvement in the development of screening protocols, no agreement exists concerning the age at which children should be screened, the exact test batteries that should be included and who should conduct the screening. This review highlights some important aspects of the history of paediatric vision screening and available evidence in support of their use to detect visual conditions in children. It also examines some of the barriers against the development of paediatric vision screening models especially in low and medium income countries.     

Advanced diagnostic procedures for evaluating the visual status of the child.

Single cell studies of cats and monkeys, recent behavioral testing methods, and improved sophisticated electrodiagnostic procedures have resulted in a new awareness of and concern for the development of the visual system. This paper will review select relevant research and highlight some of the new diagnostic vision tests presently available for the clinical assessment of infants and young children.     

选择观看法对正常婴儿双眼视力的初步评价

目的　应用选择观看法 (Preferentiallooking ,PL)初步研究国人正常婴儿视力发育状况。方法　使用自行研制的婴幼儿PL视力检测仪对 64例正常婴儿双眼视力进行测定。结果　正常婴儿的双眼视力发育与年龄增加呈高度正相关 ,视力随着婴儿年龄增长而上升 ,2月、 4月、 6月、 8月、 1 0月及 1 2月的平均视力值分别为 0 0 6、 0 1 0、 0 1 5、 0 1 6、 0 2 0及 0 2 5。结论　正常婴儿视力随着年龄增长而不断提高 ,婴儿视力的测定不仅掌握其视力发育过程 ,而且有助于早期发现婴儿视力发育迟缓。