Lea Symbols视力表在42～78个月儿童视力检查中的重复测量可信度分析

目的：探讨Lea Symbols视力表在学龄前儿童视力检查中的重复测量可信度。方法：横断面研究。 2017年4-5月对泉州市泉港区实验幼儿园的250名42～78（61.9±10.3）个月的学龄前儿童进行全面 的眼科检查,使用Lea Symbols视力表重复测量右、左眼的单眼远视力,采用LogMAR记录法记录 视力值。采用Bland-Altman分析、加权Kappa检验、组内相关系数3种统计分析方法衡量2次测量之 间的重复测量可信度。结果：3种分析方法均显示Lea Symbols视力表在学龄前儿童视力检查中的重 复测量可信度较好,2次测量间视力的差值94.3%在1行以内,2次测量的视力值之间的相关性较高 （r=0.753,P<0.001）。在139名屈光正常儿童中,2次测量的视力值（LogMAR）平均相差0.014。在 139名屈光正常儿童中,视力与月龄的相关性是显著的,月龄越大视力越好（r第1次=-0.335,P<0.001; r第2次=-0.424,P<0.001）;性别对可重复性没有影响（P=0.197）。结论：Lea Symbols视力表可用于 中国42个月及以上学龄前儿童的视力检查,可以在临床视力检查中推广使用。     

Lea图形与HOTV字母视力表对3～4.5岁儿童视力检查的比较

目的:比较分析Lea图形与HOTV字母视力表在3~4.5岁学龄前儿童视力检查中的适用情况及视力发育情况。方法:采用调查研究,以随机顺序先后应用两种视力表对广州地区两所幼儿园共133例266眼进行视力检查,视力值及其差异均用logM AR记录方法表示。结果:Lea视力较HOTV视力总体可测率高(96.24%vs92.48%),但差异无统计学意义(P>0.05)。儿童单眼两种视力差异均无统计学意义(右眼t=0.517,P=0.606;左眼t=-0.618,P=0.538)。儿童左右眼之间的视力差异均无统计学意义(Lea视力表:t=0.638,P=0.525;HOTV视力表:t=-0.897,P=0.372)。男性儿童的两种视力均优于女性儿童,但差异无统计学意义(均P>0.05)。3岁、3.5岁、4岁、4.5岁四个年龄组单眼的两种视力检查结果显示,儿童的视力随年龄增长逐渐提高,但四个年龄组间Lea视力差异无统计学意义(右眼:F=2.662,P=0.052;左眼:F=1.850,P=0.143),HOTV视力差异具有统计学意义(右眼:F=4.518,P=0.005;左眼:F=3.893,P=0.011)。结论:两种视力表都适合于3~4.5岁学龄前儿童的视力筛查;3~4.5岁儿童单眼的两种视力结果相似;视力发育与眼别、性别均无关;年龄大于3岁的儿童基本都可以接受主观视力检查,且在学龄前早期主观视力发育较快。     

Lea Symbols与Tumbling E视力表在学龄前儿童视力检查中的应用

目的比较LeaSymbols视力表与TumblingE视力表在学龄前儿童中视力的检测率、视力值和双眼间视力差异。方法对温州市某幼儿园一小班24名36～50(平均43.2±3.71)个月的儿童以随机顺序先后用LeaSymbols与TumblingE视力表检查单眼视力,视力值用logMAR记录方法来表示,用logMAR单位记录双眼视力差异。结果Leasymbols视力表的检测率为96%,Tum-blingE视力表的检测率为71%,其中33只眼能配合查Leasymbols与TumblingE,TumblingE的视力为0.26±0.10,Leasymbols的视力为0.19±0.10,两者呈线形相关(相关系数r=0.76),两者作配对t检验有显著性差异(t=6.068,p<0.0001),16名儿童用LeaSymbols测得的双眼视力差别为-0.004±0.065,用TumblingE测得的双眼视力差别为-0.019±0.067,两者呈线形相关(相关系数r=0.65),统计学分析两者无显著性差异(p=0.296)。结论Leasymbols视力表检查学龄前儿童视力特别是3～4周岁的儿童检测率高,LeaSymbols与TumblingE视力表一样能够很好地反映双眼间视力的差别,但与TumblingE视力表相比,LeaSymbols视力表存在过高估计视力的可能。视力的测定是个心理物理学过程,对于学龄前儿童,我们不能简单地根据视力小于0.8判断其弱视,而是要从儿童的认知水平来考虑。     

Lea对比度视力表在弱视治愈儿童中的应用

目的 用Lea对比度视力表检查研究正常儿童以及弱视治愈儿童的视觉功能状态,寻求Lea对比度视力表是否存在某对比度水平对弱视治愈者具有特别的敏感性。方法 正常视力儿童18例（36眼）,弱视治愈者25例（41眼）,参加实验者单眼均在最佳矫正基础上均完成100%,25%,10%以及5%对比度的Lea视力表的检查。结果 正常儿童随着Lea对比度的下降视力有显著性下降（F（3,140）=6.618,P〈0.001）,弱视治愈眼随着Lea对比度的下降视力有显著性下降（F（3,160）=17.677,P〈0.001）;弱视治愈眼Lea对比度视力在100%,25%,10%,5%对比度下均比年龄匹配的正常儿童显著低下（P〈0.05）,各对比度之间的视力的变化在5%对比度下变得更加明显（P=0.022）。结论 Lea对比度视力表可以用于临床弱视治愈儿童的视功能检查;正常儿童和弱视治愈眼的Lea对比度视力,随着对比度的下降明显降低;本研究中的弱视治愈眼仍未达到正常视觉功能,临床上需要进一步的治疗。     

Psychometric视力表对弱视儿童视力的评估作用

目的评价Psychometric视力表在弱视儿童诊治中的应用价值．拥挤现象对正常视力儿童和弱视儿童的影响是否相同。方法我院门诊5～15岁儿童113人，男65人，女48人，平均年龄（7.42±2．03）岁，用标准对数视力表和包含拥挤现象的Psychometric视力表分别检查左右眼的两种视力，比较正常眼和弱视眼两种视力的差别。结果正常视力儿童和弱视儿童的两种视力差异都有显著性（P〈0．05）。对数视力比P视力高。弱视儿童的两种视力差别比正常儿童大。不同弱视类型之间视力差别不大．不同弱视程度之间两种视力有差别。结论儿童都受拥挤现象的影响，但是弱视儿童的拥挤现象更明显。拥挤现象影响程度与弱视程度有关。与弱视类型关系不大。Psychometric视力表适合弱视患者的视力检查。     

学龄前儿童常用视力表的研究进展

学龄前期(3-6岁)是视觉发育的关键时期，及早发现并治疗学龄前儿童视觉问题至关重要。视力表是筛查儿童视觉问题的重要工具，国内常采用标准对数视力表和儿童图形视力表，而国外则常用Lea、HOTV和ETDRS视力表。已经有很多研究报道了这三种视力表在儿童视力检查中的可测性、可重复性及诊断视觉相关问题的敏感性。然而，在国内这三种视力表的应用较为有限，本文就这三种视力表的设计原理、临床中的应用及各自的特点进行综述，以便更好地了解它们在学龄前儿童中的适用性和局限性，从而为未来视力检查方法的选择和改进提供参考。     

ETDRS对数视力表在儿童视力检查中的可重复性分析

目的：探讨ETDRS对数视力表对儿童视力检查的可重复性及其影响的相关因素。方法：在流行病学调查的过程中，随机使用ETDRS对数视力表，为250位裸眼视力低于0．5和98位视力正常儿童进行裸眼视力重复检查。结果：两次视力测量之间差异的均数为0．004log±0．07；Kappa分析结果具有很好的一致性（k=0．71）；性别与视力检查一致性无明显相关（P=0．845）；年龄与视力检查一致性有显著相关性（P=0．019），年龄越小视力检查一致性越差；屈光不正与视力检查一致性也有显著相关性（P=0．000），近视度数在-1．00D—-5．00D之间的儿童视力检查一致性相对差．而正视眼的视力检查一致性较好。结论：结果提示ETDRS对数视力表适合儿童视力检查，建议推广使用。眼科学报2008；24：48-52．     

Lea Symbols电子视力表与灯箱视力表在儿童视力检查中的对比研究

目的 比较类纸屏承载的电子视力表与灯箱视力表在儿童视力检查中的准确性、一致性及差异。方法前瞻性自身对照交叉设计临床试验研究。以分层整群抽样方法选取拉萨市7所小学共1506名二年级儿童,其中男生802名,女生704名,平均年龄8.5±0.5岁。在相同测试环境下,由经过培训的专业人员使用以Lea symbols为视标的灯箱视力表和类纸屏电子视力表进行检查,两种视力表的检查顺序随机决定,并以LogMAR计数进行分析。采用组内相关系数计算两种视力表测量值的相关性,使用散点图及Bland-Altman检验图观察两种视力表测量的分布情况。结果 灯箱视力表测得平均LogMAR视力为右眼0.13±0.19,左眼0.14±0.20,电子视力表测得平均LogMAR视力为右眼0.08±0.20,左眼0.09±0.20。两种视力表测得总体视力值一致性较好且呈明显正相关趋势(ICC_OD=0.91,ICC_OS=0.89,P<0.001)。灯箱视力表和类纸屏电子视力表测量的总体平均差值为右眼0.05±0.11,左眼0.05±0.12,在各个视力范围内电子视力表测量的...     

诱导式亮度匹配手形儿童视力表

设计一种新形儿重视力表系由亮度匹配手形视标、诱导图形（鸡、鸭、狗、苹果）及动态显示装置所组成。它采用的几何增率，经统计学处理与“国家标准对数视力表”的视力值呈高度相关（r＝0．96，P＜0．001），儿童对两表的合作经间差异有非常显著的意义（x2＝43．32，P＜0．005）．表明本表适用于不能接受E形表检查的儿童，尤适用于家庭对儿童视力的监测。     

硬性透气性角膜接触镜矫正屈光不正的对比敏感度功能评价

目的检测并比较屈光不正患者分别配戴框架眼镜和硬性透气性角膜接触镜（RGPCL）时的对比敏感度功能．评价后者视觉矫正质量。方法采用自身前后对照研究,屈光不正患者56名（100眼）,近视度数为一1．00一13．00D,散光为0．50～3．75D,每只受试眼前后分别采用框架眼镜和RGPCL矫正．采用logMAR视力表检查两种方法矫正后的最佳矫正视力,使用CSV．1000E检测两种矫正方法在无眩光和有眩光下的对比敏感度功能（CSF）,绘出CSF曲线,计算CSF曲线下面积（AULCSF）。采用配对t检验比较两种矫正方法下的最佳矫正视力、各空间频率下的CSF值及AULCSF。结果配戴框架眼镜和RGPCL的最佳矫正logMAR视力分别为0．019±0．032,0．004±0．013,两者差异有统计学意义（t=-3．82,P〈O．01）。在无眩光和有眩光状态下,RGPCL矫正时的CSF曲线在各个空间频率下都高于框架眼镜,且差异有统计学意义（P值均〈0．05）。框架眼镜和RGPCL矫正时的AULCSF在无眩光时分别是1．171±0．028和1．344±0．018,有眩光时为1．143±0．022和1．268±0．025,两种状态下两种矫正方法的AULCSF差异都有统计学意义（f=-4．03、-3．13,P〈O．01）。结论RGPCL矫正屈光不正不仅可以提供更好的视力,还可以在各个空间频段提高对比敏感度,为患者提供最佳质量的视网膜光学成像,提高视觉功能。     

Visual acuity results in school-aged children and adults: Lea Symbols chart versus Bailey-Lovie chart.

PURPOSE: To compare visual acuity results obtained using the Lea Symbols chart with visual acuity results obtained with the Bailey-Lovie chart in school-aged children and adults using a within-subjects comparison of monocular acuity results. METHODS: Subjects were 62 individuals between 4.5 and 60 years of age, recruited from patients seen in five optometry clinics. Each subject had acuity of the right eye and the left eye tested with the Lea Symbols chart and the Bailey-Lovie chart, with order of testing varied across subjects. Outcome measures were monocular logarithm of the minimum angle of resolution (logMAR) visual acuity and inter-eye acuity difference in logMAR units for each test. RESULTS: Correlation between acuity results obtained with the two charts was high. There was no difference in absolute inter-eye acuity difference measured with the two acuity charts. However, on average, Lea Symbols acuity scores were one logMAR line better than Bailey-Lovie acuity scores, and this difference increased with worse visual acuity. CONCLUSIONS: The Lea Symbols chart provides a measure of inter-eye difference that is similar to that obtained with the Bailey-Lovie chart. However, the monocular acuity results obtained with the Lea Symbols chart differ from those obtained with the Bailey-Lovie chart, and the difference is dependent on the individual's absolute level of visual acuity.     

Threshold visual acuity testing of preschool children using the crowded HOTV and Lea Symbols acuity tests

PURPOSE: To compare the testability and threshold acuity levels for very young children on the crowded HOTV logMAR distance visual acuity test presented on the BVAT apparatus and the Lea Symbols logMAR distance visual acuity chart. METHODS: Subjects were 87 Head Start children from age 3 to 3.5 years. Testing consisted of binocular pretraining at near using a lap card as needed, binocular pretraining at 3 m, and threshold testing for each eye. The testing procedure, adapted from the Amblyopia Treatment Study, presented optotypes until the child was unable to correctly name or match three of three or three of four optotypes of a given size. Threshold acuity was the smallest size for which at least three optotypes were correctly identified. RESULTS: Both near and distance pretraining were completed by 71% of children for HOTV and by 75% for Lea Symbols (P =.39). The distribution of threshold acuities differed between the two tests. For the 69 eyes of 53 children who were successfully tested with both optotypes, results from the crowded HOTV acuity test were on average 0.25 logMar (2.5 lines) better than those from the Lea Symbols acuity test (P <.001). CONCLUSIONS: The proportion of children between 3 and 3.5 years of age whose monocular visual acuity could be assessed was high and was similar for the two charts tested. Crowded HOTV acuity results were better on average than results using Lea symbols. The different formats of the two tests may explain the observed differences in threshold acuity level.     

A computerized resolution visual acuity test in preschool and school age children

AIM: To study if one of the two molecules could lead to a lower number of follow up visits and intra-vitreous injection (IVI) with the same efficacy. METHODS: ELU (or “elected” in French) study is a retrospective study conducted in real life in patients presenting suboptimal response after ranibizumab IVI (phase 1) and secondary switched to aflibercept (phase 2). The number of follow up visits and IVI were compared in both phases. Visual acuity (VA) evolution and “switching” reasons were secondary analyzed. RESULTS: We retrospectively included data of 33 patients (38 eyes) with age-related macular degeneration (AMD; mean age: 77±7.7y). The number of monthly follow up visits [Median (Q1; Q3)]: was significantly lower with aflibercept (phase 2), respectively 1.0 (0.81; 1.49) visits in phase 1, versus 0.79 (0.67; 0.86) visits in phase 2. The median number of monthly IVI also significantly decreased in phase 2, respectively 0.67 (0.55; 0.90) IVI in phase 1, versus 0.55 (0.45; 0.67) IVI in phase 2. The mean VA evolution (VA final-VA initial) was similar in both phases, (P>0.05). Whatever the reason for “switching” (loss of efficacy, tachyphylaxis, tolerance problems), there was no incidence on VA evolution over the time. CONCLUSION: Our results show that switching from ranibizumab to aflibercept in “suboptimal” patients, significantly reduced the number of follow up visits and IVI, with a comparable efficacy. This decrease in visit number could improve patients’ quality of life and reduce surgical risk by reducing the number of injections.     

红色视力表远距离视功能训练在近视性弱视治疗中的疗效分析

目的：对比观察分析红色视力表远距离视功能训练在近视性弱视治疗中的疗效。方法近视性弱视患儿甲、乙两组共112例212眼,甲组62例117眼,年龄4-12岁（5.71±1.78岁）,乙组50例95眼,年龄3-12岁（5.96±1.83岁）;其中甲组轻度、中度、高度近视眼分别为21眼（17.95%）、67眼（57.26%）、29眼（24.79%）,乙组为18眼（18.95%）、55眼（57.89%）、22眼（23.16%）（χ2＝0.09,P〉0.05）;甲组轻度、中度、重度弱视眼分别为30眼（23.15%）、64眼（54.70%）、23眼（19.66%）;乙组为24眼（25.26%）、54眼（56.84%）、17眼（17.89%）（χ2＝0.133,P〉0.05）;甲组病例采用短小遮盖＋近距离视功能训练;乙组病例采用短小遮盖＋红色视力表远距离视功能训练,所有病例治疗随访时间17个月,对比分析两种治疗方法在近视性弱视治疗中的疗效。结果甲组基本治愈率为39.32%,有效率为43.59%,无效率为17.09%;乙组基本治愈率为47.37%,有效率为36.84%,无效率为15.79%,统计学检验差异无显著性（χ2＝1.434,P〉0.05）;甲乙两组治疗后轻、中、高度近视眼数分别为：4眼（3.42%）、65眼（55.56%）、48眼（41.03%）和5眼（5.26%）、67眼（70.53%）、23眼（24.21%）统计学检验差异有显著性（χ2＝6.734,P〈0.05）。结论红色视力表远距离视功能训练治疗近视性弱视疗效好,同时能更好的减少治疗后弱视眼近视度数的发展。     

新型对数视力表与“C”形对数视力表的一致性与稳定性分析

目的评价新型对数视力表与具有8个方向视标选项的“C”形对数视力表之间的一致性与稳定性。方法 横断面研究。对48例应届高中毕业生分别进行新型对数视力表与“C”形对数视力表的视力检查,采用组内相关系数（ICC）和Cronbach′s Alpha系数分析视力测量结果的重复性,采用Bland-Altman分析一致性。结果 “C”形对数视力表Cronbach′s Alpha系数在0.8以上,ICC接近0.9,新型对数视力表Cronbach′s Alpha系数接近0.8,ICC＞0.75,均显示较好的重测稳定性。2种视力表第1次和第2次视力测量均具有较好的一致性,95％一致性界限分别为（0.173,-0.133）logMAR和（0.198,-0.116）logMAR。结论 新型对数视力表检查结果稳定,和“C”形对数视力表一致性较好。     

部分遮盖法治疗大龄儿童弱视的疗效分析

目的 比较每天全遮盖健眼不同时间治疗7～12岁单眼弱视儿童的疗效.方法 对84例诊断为屈光参差性、斜视性或混合性单眼弱视的7～12岁儿童采用部分时间全遮盖健眼,随机分为每天遮盖2 h组、4 h组和6 h组.4周复查1次,记录视力及对应的logMAR值.连续随访6个月.结果每天遮盖2、4和6 h组,治疗6个月后视力提高分别为:0.17±0.09、0.25±0.12及0.30±0.13(LogMAR值),三组间差异有统计学意义(P<0.01).遮盖4 h和6 h组间视力提高,差异无统计学意义(P>0.05),但与2 h组间差异均有统计学意义(P<0.01).各类型弱视视力提高差异无统计学意义(P>0.05).结论 对于7～12岁单眼弱视儿童,每天全遮盖健眼2～6 h均能改善视力,但遮盖4 h及6 h较2 h能更有效地提高视力.     

Normal visual acuity in 17--18 year olds

PURPOSE: The aim of this work was to establish visual acuity norms in 17-18-year-olds. METHODS: In a previous, population-based study carried out in 1998, a total of 1046 12-13-year-old children were examined with a full eye examination. In 2003, 25% (n=262) of these children were randomly selected and invited to a re-examination; 147 subjects agreed to participate and 116 attended. The examined group did not significantly differ from the original sample in terms of the prevalence of ocular and visual disorders. Best corrected monocular visual acuity (VA) was assessed with the revised 2000 ETDRS logMAR chart. RESULTS: Mean best corrected VA was -0.10 logMAR across the examined group. There was no significant difference between right and left eyes. By excluding nine subjects who had significant ametropia and/or ocular or visual pathology, mean VA increased to -0.12 logMAR (SD 0.07). The mean interocular difference in VA among normal subjects was 0.04 logMAR. CONCLUSIONS: Visual acuity in teenagers is significantly better than 0.0 logMAR and the interocular difference is low in healthy eyes.