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.     

对老年性黄斑变性低视力患者进行视功能康复教育训练的研究评价

目的：本研究通过使用光学助视器，对老年性黄斑变性（ＡＲＭＤ） 低视力患者进行视觉功能训练的再教育，研究教育对低视力患者视觉康复的重要程度，同时评价低视力康复的各项指标和助视器的作用。方法：对１３９ 位ＡＲＭＤ低视力患者的最佳视力眼进行该项目的研究和跟踪，平均年龄７９ 岁（５６ ～９５ 岁） ，各患者根据个人需要，分别使用单眼望远镜、放大眼镜、显微镜、视屏放大器等；再教育训练项目：①视动刺激练习、空间定位练习、手眼协调练习；②各种阅读方法识别和训练；③认知功能，如视觉记忆或逻辑推理等诱发训练；结果：教育和训练后，９５ 例视力增加了一行以上（６７．６％ ） ，６７ 例（４８．２ ％） 能借助助视器进行有效的阅读工作；训练前的平均单字视力为１．５０／１０，训练后平均为２．１４／１０；对比敏感度视力曲线发生了改善性变化；５０ ％ 阅读速度增加，３５．６％ 保持不变，１４．４％ 有所下降，平均阅读速度为４７．０８ 字／分（ 训练前为３６．５１ 字／ 分）；生活自理能力评分显著性增加；５８％ 能书写帐单和信件。结论：可以通过开发低视力患者周边的视觉视功能进行视觉功能康复；使用助视器同时结合患者教育和训练在视功能康复中起至关重要作用；ＡＲＭＤ     

快速系列视觉呈现、全屏及纸面显示方式下汉字阅读速度的比较

目的比较快速系列视觉呈现（RSVP）、全屏及纸面显示方式下的阅读速度。获取RSVP方式下的临界字体大小和临界视力储备（RA）。方法视敏度阈值不低于1．0（矫正视力或裸眼视力）的30位被试参加本实验。用自行设计的视力表检测所有被试的视敏度阈值（3m检测距离）。测量RSVP方式下10种字体大小（4．0—33．0磅）和全屏、纸面显示方式下2种字体大小（10．0和13.0磅）的阅读速度。结果30位被试40cm阅读距离的视敏度阈值是（2．2±0．3）磅。在RSVP方式下,随着字体的增大阅读速度明显加快。当字体大小为（7．8±0．4）磅时阅读速度达到最大值：（258．0±34.4）字／min,随后保持恒定。阅读速度与RA成正相关。当RA为3．5±0.4时,阅读速度达到最大值。当RA为3．5～15．0时,阅读速度始终处于最大值。全屏显示[10磅：（354．1±58．7）字／min;13磅：（369．2±56．4）字／min]和纸面显示[10磅：（349．4±68．6）字／min;13磅：（362．1±59．3）字／min]的阅读速度之间差异无统计学意义（P〉0．05）;全屏和纸面显示的阅读速度均大于RSVP[10磅：（262.0±35．0）字／min;13磅：（258．7±34．5）字／min],差异有统计学意义（P〈0．01）。结论正常视力的年轻人在RSVP的临界字体大小是7．8磅,这提示在静态呈现方式下的临界字体应该大于7.8磅。获得最大阅读速度时的字体大小一般是视敏度阈值的3．5倍。     

高度近视白内障并低视力超声乳化术后视力分析

目的 :观察高度近视白内障并低视力患者行白内障超声乳化 +人工晶状体植入手术后视力变化。方法 :高度近视白内障并低视力患者 2 5例 40只眼 ,术前常规眼部检查 ,散瞳详细检查眼底并记录 ,使用检影验光和综合验光仪精确验光 ,汉字阅读视力表检查最佳近视力 ,手术后 6个月至 2年后进行随访 ,再次精确验光和近视力检查 ,并调查近阅读情况。结果 :(1)远视力 :2 5例 40只眼矫正远视力明显优于术前 ,5例 10只眼矫正视力≥ 0 3 ,等效球镜度为 -1 75～ -3 75D ,2 0例 3 0只眼 <0 3 ,等效球镜度为 -1 75～ -4 0 0D ;(2 )近视力 :手术后测最佳近视力明显下降 ,3 0只低视力眼最佳近视力三号字 /2 5cm ,最差不能看清初号字 ;(3 )近阅读情况调查 :3 0只低视力眼均反映近视力下降 ,出现近阅读困难 ,不能阅读书报 ;在 5例10只眼矫正视力≥ 0 3中也表现近视力下降 ,4例出现近阅读困难。 (4)解决方法 :2 0例 3 0只低视力眼患者近阅读时配戴正高屈光度数眼镜 ,移近目标至足够近距离进行阅读 ,度数 + 4 50～ + 13 0 0D ,平均 + 7 82D ,除 1只眼因黄斑功能差配戴近阅读镜近视力为四号字 / 10cm ,其余均能够完成近阅读。在 4例 8只眼矫正视力≥ 0 3中同样验配近阅读眼镜 ,屈光度 + 3 0 0～+ 6 2 5D ,完成近阅读。结     

非球面多焦点人工晶状体＋3．0D视觉功能的临床研究

目的比较三种多焦点人工晶状体（IOL）ReSTOR＋4．0D、IQReSTOR＋4．0D和IQReSTOR＋3．0D的临床效果,评估植入IOReSTOR＋3．0D后的视觉功能。设计前瞻性病例系列研究。研究对象老年性白内障患者47例（72眼）。方法对以上患者行白内障超声乳化吸除和IOL植入术,按患者自愿原则,分别植入ReSTOR＋4．0D18例（27眼）,IQReSTOR＋4．0D15例（25眼）,IQReSTOR＋3．0D14例（20眼）。比较患者术后3个月的近距离、中距离和远距离视力、对比敏感度、波前像差和离焦曲线。主要指标近距离、中距离和远距离裸眼和矫正视力,对比敏感度,波前像差,离焦曲线和问卷调查。结果术后3个月,IQReSTOR＋3．0D组裸眼中距离LogMAR视力（0．169±0．07）较ReSTOR＋4．0D组（0．256±0．08）和IQReSTOR＋4．0D组（0．252±0．08）好,差异有统计学意义（P=0．000,P=0．001）。近距离和远距离视力,三组没有统计学差异（P均〉0．05）。离焦曲线显示IQReSTOR＋3．0D组的近距离视力在…2．0D2．5D,相当于眼前40～50cm范围有一高的平台,而ReSTOR＋4．0D组和IQReSTOR＋4．0D组仅为一个点。三组患者术后3个月的夜间视力模糊、眩光和光晕没有统计学差异。结论衍射多焦人工晶状体＋3．0D较＋4．0D能够提供更好的中距离视力和一定距离范围近视力。（眼科。2010,19：84-88）     

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。     

准分子激光治疗对近视患者阅读能力的影响

目的评价准分子激光原位角膜磨镶术（laser in situ keratomileusis，LASIK）和准分子激光角膜上皮下磨镶术（laser in situ keratomileusis，LASIK时近视患者阅读能力的影响。方法将40例患者（80眼）分成两组：LASIK组（23例）和LASEK组（17例），分别于手术前和术后第1个月测量单眼的最佳矫正远、近视力及在不同对比敏感度的阅读材料下的阅读速度。时所有数据进行配时资料Studentt检验。结果手术前后所有参数在两组间没有统计学差异。术前汉字阅读视力表7号字的平均阅读速度为（232．70±48．49）字／min（LASIK组）和（230．26±45．85）字，min（LASEK组），术后为（261．32±58．28）字／min（LASIK组）和（261．83±59．71）字／min（LASEK组），两组术后均有显著性提高（t=-4．075，P=0．000；t=-3．533，P=0．004）。术前普通报纸的平均阅读速度为（260．97±38．69）字／min（LASIK组）和（268．23±28．97）字／min（LASEK组），术后为（238．52±58．40）字／min（LASIK组）和（249．75±41．56）字／min（LASEK组），LASIK组术后阅读速度有降低（t=2．417，P=0．023）；而LASEK组术前术后阅读速度差异无显著性（t=1．692，P=0．116）。结论中、低度近视患者在这两种屈光手术后能够在光线充分的环境下保留正常的阅读能力。     

新型抗 VEGF 融合蛋白 Conbercept 玻璃体腔注射治疗湿性年龄相关性黄斑变性的疗效评价

目的评估新型抗血管内皮生长因子（VEGF）融合蛋白Conbercept玻璃体腔注射治疗湿性年龄相关性黄斑变性（AMD）的疗效和安全性。方法所有患者初诊时均行视力、眼压、眼科前后节常规检查,荧光素眼底血管造影（FFA）检查、相干光断层扫描（OCT）检查。湿性AMD 的诊断依据FFA 和OCT 中典型性脉络膜新生血管（ CNV）的显示。所有患眼均采用“3＋ PRN”方案进行眼内注射Conbercept 治疗,眼内注射按规范流程标准进行操作。评估指标包括：视力、中心视网膜厚度（CRT）、荧光素渗漏率和CNV面积。根据再注射标准进行眼内重复注射,随访观察≥6个月。结果湿性AMD 30例（35只眼）治疗前基线平均视力（logMAR）为0．699±0．523,平均CRT为（354．56±120．92）μm,荧光素渗漏率为100．00％（35／35）,平均CNV面积为（9．82±6．35）mm2。在观察终点时（初次注射后6个月）平均视力（logMAR）为0．305±0．357,平均CRT为（276．08±144．40）μm,荧光素渗漏率为5．71％（2／35）,平均CNV面积为（5．63±3．47）mm2。与治疗前基线比较视力显著提高（P ＜0．01）,CRT、荧光素渗漏率及CNV面积显著降低（P ＜0．01）。视力和CRT在初次治疗后1个月内得到快速的改善,之后视力保持缓慢提高,CRT保持缓慢降低。所有患眼无一例发生严重不良反应。结论新型抗VEGF融合蛋白Conbercept玻璃体腔注射治疗湿性AMD能够显著提高视力和恢复黄斑结构,起效快,并且持续改善,安全性高,无眼局部及全身不良反应,值得临床推广应用。     

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。     

中文简体与繁体引起的眼调节反应和近距离工作致暂时性近视回退的比较

背景近视的流行病学研究发现,中国香港和台湾地区的近视发病率高于中国大陆。中国台湾、香港地区的通用文字为中文繁体字,而大陆使用的则是中文简体字,通用阅读文字的不同是否与近视发生率的差异有关,繁体字和简体字阅读状态是否与近视发生存在关联值得关注。目的检测同种字体随着字号增大所引起调节反应的量和近距离工作导致暂时性近视（NITM）回退水平的变化规律,探讨因中文字构架差异所诱导的调节发生的异同及其内在的关系。方法选取22名受试者,其中男15名,女7名;年龄24～29岁;等效球镜屈光度为＋O．50—-6．00D,平均等效球镜屈光度为（-1．86＋2．34）D。采用快速序列视觉呈现方式（150字／min）（RSVP）软件提供9pt、12pt的中文简体和繁体阅读视标,GRANDSEIKO—WV5500型红外自动验光仪测量受试者的调节反应;受试者配戴全矫等效球镜随机阅读眼前（角膜平面）33cm处计算机显示屏上的中文简体字与繁体字（调节刺激为3D）,字号包括9pt和12pt,在阅读2min时测量调节反应,阅读每种文字10rain测量调节反应,阅读10rain后闭眼休息10s测远用屈光度数,再间隔58、10s继续测远用屈光度数。采用单因素方差分析比较不同字体和不同字号对于调节反应和NITM的影响。结果中文简体与中文繁体引起的调节反应量均表现为调节滞后,滞后量分别为（1．11±0．38）、（0．95±0．43）、（1．18±0．33）、（1．06±0．28）D,其中简体12pt与繁体9pt引起的调节滞后量差异有统计学意义（t=5．56,P=0．02）。4种视标均引起一定的NITM,分别为（-0．45±0．45）、（-0．47±O．46）、（0．45±O．82）、（-0．46＋0．78）D,各视标引起的NITM回退水平的总体差异无统计学意义（F：0．01,P=0．99）。结论短时间阅读简体中文与繁体中文因在调节滞后机制方面存在差异,可能与地区近视发生率的差异有关,而在NITM回退机制上可能与地区近视发生率差异无关。     

The limitations imposed on reading by low vision aids.

INTRODUCTION: The changes that occur in the reading eye movements of normally sighted readers were measured as they used hand magnifiers to identify how these devices contribute to the slow reading of visually-impaired patients. METHODS: Subjects inexperienced in magnifier use read texts containing two sizes of print, using hand magnifiers of two different powers, held at two different eye-to-magnifier distances. The effect of magnification (up to 13.5x) and field-of-view (FOV) (2-45 characters) could be assessed independently. RESULTS: Reading speed decreased with increasing magnification because the size of the saccades did not increase in proportion to the magnification: for a given level of magnification, decreasing the FOV and decreasing the viewing distance both reduce the size of the saccades even further. The overall reading speed is only slowed significantly when the FOV restriction is extreme (two characters' width). CONCLUSIONS: Two mechanisms seem to be used spontaneously by normally sighted readers to mitigate the limitation of reading speed created by the shortened saccades: head movement in the direction of reading and retinal image slip during fixation.     

Reading with a head-mounted video magnifier.

PURPOSE: This study compared the effectiveness of a head-mounted video magnifier, low-vision enhancement system (LVES), with closed-circuit TV (CCTV) and large print as a device or means of improving reading performance in people with low vision. METHODS: The reading performance of ten low-vision participants was assessed in two ways: (1) By measuring reading speed as a function of print size with LVES and without LVES, and (2) by comparing reading speed and comprehension of news articles using the LVES vs. a popular non-head-mounted video magnifier, the CCTV. RESULTS: Maximum reading speeds with LVES matched the maximum reading speeds with unaided vision attained by enlarging print. The critical print size (the smallest print size that could be read at maximum reading speed) improved significantly for all participants using LVES compared with unaided vision. When comparing reading performance using LVES and CCTV, we found that reading speed and comprehension for the two conditions were equivalent. The two low-vision participants with lowest acuities (20/640 and 20/960) could not read the 10-point newspaper articles with LVES, even with an 8 D auxiliary reading lens that permitted a very close reading distance. CONCLUSIONS: Head-mounted video magnifiers, such as LVES, can support good low-vision reading performance, but the restricted range of magnification may limit the usefulness of the device as a reading magnifier for people with very low acuity.     

Low vision correction for high myopia.

High myopia is favorable for low vision corrections because the vision has usually been poor since childhood and the person has been able to read at close range, producing magnification. For near vision, in addition to bringing objects close, magnification is produced by high-add bifocals, trifocals, strong near vision spectacles and nonspectacle magnifiers. Hand magnifiers held at a distance from the eye are used with the spectacle correction. This paper describes the Visolett, used without correction or near vision correction, as the preferred non-spectacle magnifier because the reading area is self-illuminated, it doubles the approach magnification, rests on the paper, is simple to use, produces binocular vision, and attracts the least attention. Combination method of magnification consists in the use of the Visolett in addition to a spectacle magnifier, which doubles the magnification.     

不同助视器在低视力学生阅读康复中的应用

目的明确新型非球面光学助视器与电子助视器在低视力学生阅读康复方面的作用,为临床及低视力康复工作提供参考。方法前瞻性临床对照研究。选取广州市培英职业学校的低视力学生30例,年龄（21.1±3.0）岁。每名受检者分别在不使用助视器、使用新型非球面光学助视器和便携式电子助视器3种条件下阅读。记录不同条件下受检者的持续时间、阅读距离、阅读速度、换行时间和错误率。数据比较采用单因素方差分析,两两比较采用Bonferroni法检验。结果不使用助视器、使用新型非球面光学助视器和便携式电子助视器在阅读持续时间[（4.35±2.82）min vs. (7.27±4.50）min vs. (10.71±3.09）min,F=4.60,P<0.01],阅读距离[（7.44±4.40）cm vs. (13.38±7.07）cm vs. (20.97±6.84）cm,F=11.21,P<0.01],阅读速度[（35.64±24.01）字/min vs. （49.41±24.96）字/min vs. （65.59±20.03）字/min,F=13.77,P<0.01]、换行时间[（1.52±1.13）s vs. （2.24±1.25）s vs. （3.42±0.94）s,F=7.40,P<0.01]和错误率[（10.34±11.01）% vs. （5.84±3.61）% vs. （5.26±2.72）%,F=1.79,P<0.05）]上的差异有统计学意义。其中便携式电子助视器在阅读持续时间、阅读距离、阅读速度上均优于新型非球面光学助视器（P<0.0167）;新型非球面光学助视器在阅读持续时间、阅读距离、阅读速度上优于不使用助视器（P<0.0167）;在错误率上便携式电子助视器、不使用助视器与新型非球面光学助视器相比差异无统计学意义（P＞0.0167）,便携式电子助视器错误率低于不使用助视器（P<0.0167）。换行时间上便携式电子助视器、新型非球面光学助视器长于不使用助视器（P<0.0167）,便携式电子助视器长于新型非球面光学助视器（P<0.0167）。结论助视器对于低视力学生在阅读上有很大的帮助;便携式电子助视器总体上明显优于新型非球面光学助视器。     

Comparison of reading speed in normal observers through different forms of equivalent power low vision devices

Compensation at near for vision loss can be achieved using a variety of equivalent forms of low vision magnifiers. Each has inherent advantages and disadvantages in terms of field, working distance, etc. We compared the reading speed of 60 trained, normal observers with 4 commonly prescribed types of low vision devices of +12 D equivalent power (spectacles, hand magnifier, stand magnifier, and telemicroscope) to their normal reading speed. Although there was individual variance in performance, reading speed with all the devices was generally within 20% of normal reading speed. Implications are that in terms of differences in reading speed for normals, the form of the low vision device is not as significant as acquiring proficiency in the use of the selected device.     

Designing half-eye binocular spectacle magnifiers

The process of designing half-eye frames with a smaller than usual eye size and narrower distance between lenses (DBL) in order to produce additional base-in prism effect is described. This method enhances binocular function while the spectacle magnifier is used. The design also provides a lighter, thinner, and cosmetically more acceptable optical aid. Binocular half-eye spectacle magnifiers are useful optical aids, especially for patients with binocular vision, because they are produced in strong powers with strong prism effects incorporated in the lenses. The magnifiers range in power from +6.00 D [symbol: see text] 8 delta base-in to +14.00 D [symbol: see text] 18 delta base-in for vision ranging from 20/60 (6/18) to 20/320 (6/96). Binocular half-eye spectacle magnifiers are recommended for prolonged reading because the strong base-in prism effect relieves the convergence effort, also providing a large field of vision with both hands free.     

Determining magnification for reading with low vision

Background : In the past, practitioners have used distance and/or near visual acuity (VA) to calculate required magnification for low vision aids. Magnification was usually under‐estimated when compared with the final magnification prescribed. Recent studies have emphasised the importance of acuity reserve in determining the required magnification for optimum reading rate. Two different approaches have been proposed for the appropriate acuity reserve to use in calculating magnification. These are a fixed acuity reserve of 0.3 log unit or an individual determination of optimum acuity reserve. The aim of this study was to investigate the magnification and reading rates with low vision aids selected by the two methods. Methods : Nineteen low vision subjects with age‐related macular degeneration (AMD) who were experienced magnifier‐users were recruited. Reading rates and near VA with low vision aids determined by the fixed and individual acuity reserve methods were compared with the same measures made with the subjects' own magnifiers. Results : There were no significant differences in reading rate and near VA measured with low vision aids selected by either the fixed or individual acuity reserve methods or the subjects' own magnifiers. Reading rate with low vision aids was not significantly different from reading rate for large print with conventional near additions. Thus, for experienced users, magnifiers do not cause reduced reading rate. Conclusions : The fixed acuity reserve method is simple to apply as only near VA and print size of the target reading task are required. For the individual acuity reserve method, reading rates at different print sizes need to be measured. We recommend the use of a fixed acuity reserve (0.3 log unit) for the calculation of required magnification for low vision patients. If near VA or reading rate are not satisfactory with the magnification calculated by this method, individual assessment of required acuity reserve is necessary.     

Effect of light-emitting diode colour temperature on magnifier reading performance of the visually impaired

Background: As light‐emitting diodes become more common as the light source for low vision aids, the effect of illumination colour temperature on magnifier reading performance was investigated. Methods: Reading ability (maximum reading speed, critical print size, threshold near visual acuity) using Radner charts and subjective preference was assessed for 107 participants with visual impairment using three stand magnifiers with light emitting diode illumination colour temperatures of 2,700 K, 4,500 K and 6,000 K. The results were compared with distance visual acuity, prescribed magnification, age and the primary cause of visual impairment. Results: Reading speed, critical print size and near visual acuity were unaffected by illumination colour temperature (p > 0.05). Reading metrics decreased with worsening acuity and higher levels of prescribed magnification but acuity was unaffected by age. Each colour temperature was preferred and disliked by a similar number of patients and was unrelated to distance visual acuity, prescribed magnification and age (p > 0.05). Patients had better near acuity (p = 0.002), critical print size (p = 0.034) and maximum reading speed (p < 0.001), and the improvement in near from distance acuity was greater (p = 0.004) with their preferred rather than least‐liked colour temperature illumination. Conclusion: A range of colour temperature illuminations should be offered to all visually impaired individuals prescribed with an optical magnifier for near tasks to optimise subjective and objective benefits.