儿童低视力的视觉康复

儿童低视力的视觉康复备受关注。视功能和功能性视力是研究视觉损失的两个重要方面。儿童低视力的早期干预得到神经生物学理论和发育理论的支持,功能性视力的评估是早期干预的关键。儿童低视力的视觉康复主要包括视功能训练、助视器的使用、改善环境及特殊教育。建立完善的低视力服务体系,以实现低视力儿童的视觉康复。     

视觉综合评估与训练在0～6岁儿童低视力中的应用

目的 探讨和分析视觉综合评估与训练在0～6岁儿童低视力中的应用效果。方法 收集2020年5月至2022年5月0～6岁低视力儿童159例为研究对象,依据不同的低视力原因分为3组,A组27例为单纯脑性视觉障碍组,B组109例为单纯低视力组,C组23例为混合组。比较三组患儿阅读能力情况,三组患儿干预后的视力变化情况以及最佳矫正视力,并在训练前后分别采用SIFS量表进行评估。结果 通过训练干预后,C组患儿阅读速度明显快于A组、B组患儿(P<0.05),C组患儿阅读距离长于A组、B组患儿(P<0.05),三组患儿在阅读错误率方面无明显差异(P>0.05)。与A组、B组相比,C组患儿最佳矫正视力效果明显更优(P<0.05)。训练干预后C组患儿SIFS评分各维度明显高于A组、B组患儿(P<0.05)。结论 不同病因的低视力儿童针对性制定出低视力视觉评估与康复的诊疗常规,保证低视力儿童康复的效果,提高低视力儿童的生存质量。     

低视力者阅读速度的单,双眼比较和与临床指标关系

为比较低视力者单、双眼阅读速度有无不同，探讨哪些临床指标对阅读速度有较大影响，本文采用Ｍｉｎｎｅｓｏｔａ低视力阅读测试法测量了９４例低视力者阅读速度，结果提示双眼阅读比视力较好眼单独阅读速度快７％；视力较好眼阅读速度明显高于差眼。阅读速度与视力相关系数是０．３４１（ｆ＝１２．１２，ｐ＝０．０００８），视力对阅读速度的相关效果为１１．６％；阅读速度与年龄的相关系数为０．４６３（ｆ＝２５．０３，ｐ＝０．０００１），年龄对阅读速度有２１．４％的相关效果。用视力和年龄两个指标一起估价阅读速度比用单一标准更好，它们与阅读速度相关系数为０．６２７，有３９．４％的相关效果。此外，受试者的视野情况对其阅读速度也有较大影响。     

低视力青少年电子助视器阅读速度初步研究

目的:评估低视力青少年使用电子助视器对其阅读速度的影响.方法:在泉州市盲校筛查10名使用光学助视器有阅读能力的低视力青少年学生进行屈光矫正和常规外眼、内眼检查,分别测量其使用各种光学助视器及电子助视器阅读5号字卡的阅读速度.结果:10名低视力青少年学生在使用光学助视器后阅读速度为(18.50±6.54)字/分,使用电子助视器后阅读速度为(34.36±5.06)字/分,两组比较差异有统计学意义(P<0.05).低视力青少年的近视力与阅读速度无关(P>0.05).结论:使用电子助视器较光学助视器可以明显提高低视力青少年的阅读速度,不同病因所致的低视力青少年其近视力与阅读速度无关.     

盲/低视力儿童视力康复和阅读功能研究

目的：观察盲校及低视力门诊的15周岁以下患者，用低视力助视器对其视力特别是阅读功能进行康复和评估。方法：总共有55位来自盲校和低视力门诊的儿童，其好眼的最佳远矫正视力都低于4．5，进行低视力助视器的验配和训练，然后进行望远镜助视器视觉评价、近用助视器视觉评价和在配戴近用助视器的基础上，对患儿的阅读功能进行评怙。结果：戴远用助视器前后盲童的脱盲率为33、3％，戴运用助视器前后低视力患儿的脱残率为87．1％。戴低视力助视器前后患儿阅读四号字的速度差异有显著性(t=5．238；P=0.001)；戴低视力助视器前后患儿阅读小五号字的速度差异有显著性(t=4．818；P=0．008)。结论：低视力助视器对盲／低视力患儿视觉康复有效，不仅可有效地改善视力，而且可提高阅读速度，对患儿进一步接受教育极其重要。     

助视器在低视力儿童中的应用

目的探讨自行来院就诊低视力儿童的病因及低视力康复疗效,方法对门诊筛查视力低常儿童进行散瞳验光、眼底等检查,诊断为低视力者,应用远用、近用助视器进行视力康复训练;结果在25例低视力儿童中,(1)病因以先天性眼球震颤合并屈光不正多见,占76.00%;(2)20例选择康复远视力,最佳矫正远视力在0.1～<0.3,用4X、6X单筒近距远距观察镜康复远视力达到≥1.0,脱残率100%;(3)5例选择康复近视力,最佳矫正近视力<0.3~0.1,经过使用2.5X、3X、4X直柄放大镜和2.5X木马放大镜康复近视力≥0.5,近视力康复有效率100%。结论应用助视器能有效提高低视力儿童的远、近视力和视觉质量,让患儿有机会具备接受正常教育的用眼条件,因此,早发现、早诊断、早矫正、早康复,对低视力儿童的身心健康、拓宽知识领域、升学、就业具有积极地意义。     

儿童低视力康复概况

视觉信息是人获取外界信息最主要的来源。儿童处于生长发育的重要阶段,若视力低下,将严重影响儿童生理及心理发育,带来较之成人更为严重的影响,且儿童低视力的康复也与成人有所不同。本文对低视力的新标准、儿童低视力发病现状、常见病因、治疗特点及方法等进行综述。     

老年黄斑变性低视力患者的视觉康复

应用光学助视器,对14例(25眼)老年黄斑变性低视力患者作了视觉康复.经用远用助视器,25眼中的24眼(95%)远视力有改善,其中12眼(48%)远视力≥0.4;经用近用助视器,全部眼(100%)的近视力有改善,13眼(52%)近视力达≥0.5,10例患者可阅读5号中文印刷体,阅读成功率达71.4%.结果表明助视器的应用对改善老年黄斑变性低视力患者的远、近视力是一种有效方法.     

矫正屈光不正对儿童低视力康复的意义

目的 探讨有屈光不正的低视力儿童戴矫正眼镜后对应用助视器提高视的效果。方法 经散瞳验光 后视力有提高或改善者,予以配镜。然后再应用远用双筒与单筒望镜式助视器。结果 ３５０例中有９００例（占２５％）经验光配镜后视力均有一定程度的提高与改善,在这９０例中不戴镜直接用助视器时,其脱残率（视力提高到０．３以上）为５４．４％,而在戴镜基础上再应用助视器,则脱残率为８３．３％,两者之间差异有着非常显著性意义（     

Reading errors made by children with low vision.

Previous research has shown that, on average, children with low vision lag their sighted peers in general reading development (in terms of speed, accuracy and comprehension). This study sought to examine this apparent lag by comparing the reading profiles of 25 normally sighted readers (mean age 8 years 8 months) with 25 low vision readers. The children were tested using a reading test (the Neale Analysis of Reading Ability, NARA) and were matched on the reading accuracy score produced by the test. Therefore in terms of the reading accuracy scores (and reading ages) derived from the NARA both groups were the same. The low vision readers were on average older than the normally sighted children (mean = 10 years, 5 months). When the reading profile (i.e. accuracy, comprehension and speed) was examined in the same analysis no significant effect was revealed [d.f. = 1, 48; F = 0.05; p > 0.1], but a general lag for these children is suggested (in keeping with previous research). However, a closer analysis of the reading error profile revealed the most common reading errors made by all readers in the analysis were either mispronunciations or substitutions. The low vision readers were more prone to making substitution errors than mispronunciations and the reverse was true for normally sighted readers [d.f. = 1, 48; F = 7.1; p < 0.05]. This indicates that the reading strategies adopted by low vision readers may differ from those of normally sighted readers of the same apparent reading ability.     

视觉性助视器在低视力阅读康复中的作用

目前关于不同类型助视器在低视力阅读康复效能方面的研究结果不尽一致,本文通过文献复习,综述了当前各种视觉性助视器在低视力患者阅读康复方面的作用,包括大字印刷和放大镜的作用,使用不同光学助视器的阅读比较,使用不同电子助视器的阅读比较,使用光学助视器与电子助视器阅读的比较,非光学助视器影响阅读的相关因素如对比敏感度、阅读材料的印刷参数(行间距、字间距、字母间距、字体大小及长度、每行字数等).     

Improvement of reading speed after providing of low vision aids in patients with age‐related macular degeneration

Purpose: Age‐related macular degeneration (AMD) is the most common cause of severe visual impairment, including loss of reading ability, among elderly persons in developed countries. The aim of the present study was to evaluate reading ability before and after providing of appropriate low vision aids. Methods: Five hundred and thirty patients with different stages of AMD (age 82 ± 8 years) were included in this retrospective study. All patients underwent a standardized ophthalmological examination including evaluation of magnification requirement and careful providing of low vision aids. Before and after the provision of low vision aids, reading speed [words per minute (wpm)] was evaluated using standardized reading texts. Results: For the whole group, the average best‐corrected distance visual acuity of the better eye was 0.18 ± 0.15, with 69% of patients having visual acuity of 0.1 (20/200) or better. The mean magnification requirement was 7.4 ± 6.3‐fold (range 2–25). Visual rehabilitation was achieved with optical visual aids in 58% of patients, whereas 42% of patients needed electronically closed‐circuit TV systems. Mean reading speed was 20 ± 33 wpm before and increased significantly to 72 ± 35 (p < 0.0001) after the provision of low vision aids for the whole group. Between patients with visual acuity < 0.1 and patients with visual acuity of 0.1 or better, there are highly significant differences in reading speed before (0.4 ± 3.8 versus 20 ± 28 wpm, p ≤ 0.0001) and after providing of visual aids (40 ± 13 versus 84 ± 30 wpm, p ≤ 0.0001). Patients with severe visual impairment (visual acuity ≤ 0.1) showed significantly lower improvement of reading speed compared to patients with visual acuity of 0.1 or better following rehabilitation (p ≤ 0.0001). Before providing of low vision aids, only 16% of patients were able to read; in contrast, reading ability was achieved in 94% of patients after the provision of low vision aids for the whole group. Conclusion: Our results indicate the great value of low vision rehabilitation through adequate providing of vision aids for the improvement of reading ability, with a highly significant increase of reading speed without training of eccentric viewing in patients with retained central fixation. The prompt implementation of low vision aids in patients with macular degeneration will help them to maintain and regain their reading ability, which can lead to an increase in independence, communication, mental agility and quality of life.     

Reading performance in children with low vision

Purpose: While educators and optometrists are concerned with reading efficiency in children with low vision, in most low vision assessments, children's reading performance is assessed only by a brief evaluation of reading fluency. We examined the relationships between clinical vision measures and reading performance in children with low vision. Methods: Subjects were 71 students with low vision, aged seven to 18 years. The vision and reading performance measures were: high contrast distance visual acuity, contrast sensitivity using both the Pelli‐Robson and LH symbol charts, near text visual acuity and reading rates on a range of print sizes. Results: Most children achieved maximum reading rate at print sizes between 2.5 and seven times larger than threshold print size. Maximum reading rate increased significantly with age and near visual acuity. There was no significant relationship between reading rate and contrast sensitivity. Conclusions: The majority of children with low vision can achieve near normal reading rates with magnification. Age is the strongest predictor of reading rate in children with low vision. They need print sizes well above threshold to achieve maximum reading rate. Routine contrast sensitivity testing of visually impaired students is not indicated for reading assessment.     

The effect of font and line width on reading speed in people with mild to moderate vision loss

PURPOSE: The aim of this study was to evaluate the effects of print size, typeface, and line width on reading speed in readers with mild to moderate sight problems. METHODS: A total of 43 patients, most of whom had mild cataract or glaucoma with acuity 6/30 or better (median age = 72; range = 24-88 years), read aloud a selection of texts presented randomly in four sizes (10, 12, 14 and 16 point), for each of four typefaces [Foundry Form Sans (FFS), Helvetica (HV), Tiresias PCfont (TPC), Times New Roman (TNR)] at a standard line width of 70 characters and a viewing distance of 40 cm. A subset of letter sizes and typefaces were tested at two additional line widths (35, 90). RESULTS: As expected, reading speed increased with print size from a median of 144 words min(-1) for 10-point text to 163 words min(-1) for 16-point text (repeated measures anova, p < 0.0001). There was also a significant effect of typeface with TPC being read about 8 words min(-1) faster, on average, than the other fonts (159 words min(-1) for TPC vs 151 words min(-1) for the other fonts, p < 0.0001). However fonts of the same nominal point size were not equivalent in actual size. When adjusted for the actual horizontal and vertical space occupied, the advantage of TPC was eliminated. There was no effect of line width (p > 0.3). Data from the present study were extrapolated to the general population over age 65. This extrapolation indicated that increasing minimum print size from 10 points to 16 points would increase the proportion of the population able to read fluently (>85 words min(-1)) from 88.0% to 94.4%. CONCLUSION: This study shows that line width and typeface have little influence on reading speed in people with mild to moderate sight problems. Increasing the minimum recommended print size from 10 points to 14 or 16 points would significantly increase the proportion of the population able to read fluently.     

Reading speed test for potential central vision measurement

This study examines the validity and reliability of a reading speed test as a measure of potential central vision. Reading speed was calculated in words per minute (wpm) from the time taken to read 30 words of 1.20 logMAR size text. Scores were obtained from subjects with cataract (n = 48), macular disease(n = 35), peripheral vision loss(n = 14) and normal eyes (n = 10). Subjects with macular disease (27.0 +/- 13.2 wpm) read much slower than subjects with cataract (91.9 +/- 13.6 wpm). Little difference was found between subjects with cataract, peripheral vision loss (91.5 +/- 14.7 wpm)and normal eyes (103.8 +/- 15.5 wpm). Repeat testing gave values within +/- 16% of reading speed. These results suggest that a reading speed test using large text could be useful as a potential central vision test in cataract patients.     

视力低常的学龄前儿童屈光不正的分布规律研究

目的:观察与研究锦州市1 170例学龄前儿童视力低常的儿童屈光不正的分布规律.方法:抽取锦州市城区10所幼儿园,对3～6岁学龄前儿童进行视觉状况调查,分别进行视力检查、眼位检查、屈光状态检查、眼科常规检查以及立体视检查等.对于视力低于0.8的儿童进行散瞳验光.结果:(1)视力低常率:3岁为6.37％,4岁为7.79％,5岁为15.24％,6岁为8.93％,5岁儿童低常率明显高于其他年龄组,差异有显著性(P＜0.05);(2)视力低常眼病分布:视力低常患者中,屈光不正占95.61％.屈光不正分布:远视71.67％,其中3岁为75.00％,4岁为78.26％,5岁为75.44％,6岁为54.17％;近视17.50％,其中3岁为6.25％,4岁为13.04％,5岁为17.54％,6岁为29.17％;混合散光10.83％,其中3岁为18.75％,4岁为8.70％,5岁为7.02％,6岁为16.67％;(3)弱视情况:弱视患病率4.27％.对弱视相关因素调查显示,屈光参差性占36.00％,轻度66.67％,中度27.78％,重度5.56％;斜视性占16.00％,轻度25.00％,中度62.50％,重度12.50％;形觉剥夺性占2.00％,轻度0％,中度0％,重度100.00％.结论:学龄前儿童年龄较大者比年龄较小者视力较好,说明年龄的增长儿童视功能发育逐渐成熟.屈光不正中各组比例提示,远视是3～6岁学龄前儿童视力低下的主要原因.近视、斜视、弱视等因素所占比例提示普查手段十分重要,应早发现早治疗.