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...     

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。     

灯箱视力表与Freiburg电子视力表应用对比研究

目的 比较灯箱视力表与Freiburg电子视力表结果的一致性与可重复性,评价Freiburg电子视力表的临床应用价值。设计 诊断性技术评价。研究对象 空军杭州航空医学鉴定训练中心的工作人员86例,平均年龄（26.3±2.1）岁。方法 所有入选者均随机由2位固定检查者分别使用灯箱视力表和Freiburg电子视力表进行检查,两种视力表检查的顺序随机决定。所有检查均在同一房间内完成,房间内亮度小于3 lux。检查距离均为3 m。对不同视力表间与检查者间测量重复性采用配对t检验比较结果的差别并计算相关系数r值。主要指标 使用两种视力表获得的logMAR视力。结果 在检查者一,用灯箱视力表查,被检者logMAR视力为0.19±0.23,Freiburg电子视力表0.20±0.15,两者差值为-0.011±0.141,差异无统计学意义（t=-0.741, P=0.461）,但有显著相关性（r=0.808,P=0.000）。在检查者二,用灯箱视力表查,被检者logMAR视力为0.32±0.25,Freiburg电子视力表为0.20±0.15,两者差值为-0.118±0.151,差异有统计学意义（t=7.191, P=0.000）及显著相关性（r=0.810,P=0.000）。均用灯箱视力表,检查者一、二的差异有统计学意义（F=11.872,P=0.001）,两者显著相关（r=0.938,P=0.000）。而均用Freiburg电子视力表,检查者一、二的差异无统计学意义（F=0.019,P=0.890）,两者显著相关（r=0.986,P=0.000）。结论 Freiburg电子视力表受检查者因素的影响小于灯箱视力表,其在不同测量者间的可重复性优于灯箱视力表。（眼科, 2013, 22: 117-120）     

改良液晶视力表初步应用

目的 探讨一种改良液晶视力表实际应用的可行性。方法 前瞻性对照研究。选取吉林大学第二医院眼科医护人员33例,男8例,女25例,年龄（27.4±8.5）岁,先使用灯箱视力表再使用改良液晶改装后的液晶视力表对其进行视力检测。由同一名检查者对受检者双眼进行测量。使用Wilcoxon符号秩和检验和Bland-Altman法评估2种测量方法的一致性。结果 灯箱视力表和改良液晶视力表测量的视力值分别为4.2～5.2（4.9）和4.2～5.1（4.9）,2种方法测量结果的差异无统计学意义（Z=-0.307,P＞0.05）。Bland-Altman图显示2种测量方法具有较好的一致性,其95%一致性界限为-0.168～0.162。结论 应用改良液晶视力表检查视力和灯箱视力表具有较高的一致性。对于特殊患者,改良液晶视力表或许更具优势。     

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。     

噪声视力表在儿童视力检查中的可重复性分析

目的探讨噪声视力表对儿童视力检查的可重复性及其相关影响因素。方法在门诊首诊患儿中,随机选择无理解障碍及除屈光不正外无其他器质性眼病儿童200例,使用噪声视力表进行噪声视力重复检查。采用配对t检验进行统计学分析。结果两次视力测量之间差异的均数为O.03行,（P=0.515）;两次视力测量结果按性别分组无明显差异（P=1.0,P=0.262）;按年龄分组亦无明显差异（P=0.159,P=0.786）;按屈光不正分组,其中近视组两次视力测量结果有明显差异（P=0.010）。近视儿童视力检查一致性较差,而正视及远视儿童的视力检查一致性较好（P=0.133,P=0.083）。结论结果提示噪声视力表适合儿童视力检查,建议推广使用。     

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．     

ETDRS表原理和使用方法及其与Snellen视力表的比较

早期糖尿病视网膜病变治疗研究（early treatment diabetic retinopathy study,ETDRS）视力表是在Bailey-Lovie视力表基础上发展出来专门用于临床试验的视力表,其原理较Snellen视力表科学和合理,精确度和可重复性都高于后者,检查所耗时间较后者长,其logMAR视力结果可直接用于视力统计。ETDRS视力表能通过不同测试距离（4、2、1 m）对极低视力进行量化和评分,并且不同测试距离视力值可相互转化。但1 m以下测量时理论值和实际测量值存在较大误差,为了避免夸大视力改进或丢失的情况,应谨慎对待不同测试距离的转化值。     

拥挤Kay图片视力表在学龄前儿童视力筛查中的应用

目的：采用拥挤Kay图片视力表检测学龄前儿童视力,并和标准对数视力表检测结果进行比较,探讨2种视力表检测结果是否具有一致性,以补充不能完成标准对数视力表检测的学龄前儿童的视力筛查。方法：前瞻性自身对照研究。于2021年1─5月随机选取济南市章丘区某幼儿园152名学龄前儿童进行全面眼科筛查,分别使用拥挤Kay图片视力表及标准对数视力表对其进行视力检测,并采用Wilcoxon检验进行2种视力差异性的比较,Spearman秩相关分析及Bland-Altman分析进行相关性及一致性分析。结果：152名儿童参与筛查,其中129名儿童屈光状态正常且能配合2种视力表检测。129名儿童中男74名,女55名,年龄为（52.3±7.0）个月;拥挤Kay图片测得LogMAR视力为0.10（0.09,0.10）,标准对数视力表视力为0.10（0.10,0.22）;2种视力检查方法有较好的相关性（r=0.436,P<0.001）,拥挤Kay视力表检测结果略高于标准视力表约0.04 LogMAR,差异有统计学意义（Z=-6.124,P<0.001）,Bland-Altman散点图显示98.4%的点均在一致性范围内;参与筛查儿童Kay图片视力检查配合度更高（χ2=18.007,P<0.001）。不同月龄拥挤Kay图片视力检测结果差异有统计学意义（H=13.791,P=0.003）,随年龄增长,视力呈递增趋势。结论：拥挤Kay图片视力表用于学龄前儿童视力检测,患儿配合程度高,其结果与标准对数视力表相比有较好的一致性,但Kay图片视力表所检查的视力结果高于标准视力表约0.04 LogMAR,在参考视力结果时应相应调整视力标准。     

灯箱视力表与电脑视力表临床应用对比研究

目的:通过与灯箱视力表的对比研究了解电脑视力表的临床使用价值。方法:选取初三学生63例(126眼)同时用灯箱和电脑视力表进行远用视力检测,对视力检测值进行配对检验。结果:两种视力表检测值的t检验等于1.2671,P>0.20,两种视力表的检测在统计学上无显著性差异。结论:电脑视力表和灯箱视力表在临床上具有相同的应用价值,可以推广和普及。     

儿童视力自动检测系统在婴幼儿视力评价 中的初步应用

目的：采用北京大学第一医院与北京大学信息科学技术学院、心理与认知科学学院共同研制开发的 儿童条栅视力自动检测系统（AACP）对婴幼儿视力进行测量,探讨该系统的应用价值。方法：前瞻 性临床研究。于2018年2月至2021年10月利用北京大学多个院系联合研制开发的AACP,对5个月 ~6岁儿童进行视力自动检测,并同时使用条栅视力检测卡（TAC-II）进行人工检测,将2种检测所得 结果做对比研究。采用Wilcoxon检验进行2种视力间的差异比较,Spearman相关进行相关性分析, Bland-Altman图进行一致性分析。结果：33例（66眼）3~6岁儿童全部完成AACP与TAC-II的双眼视 力检测,其中30例（54眼）儿童完成AACP与TAC-II的单眼视力检测,双眼视力检查完成率100%, 单眼检查完成率90.0%。194例（388眼）5~30个月龄婴幼儿中,141例（282眼）完成2种检测方法的双 眼视力检测并得到有效数据,完成率为72.7%。33例3~6岁儿童的AACP与TAC-II双眼视力及单眼视 力均呈正相关（r=0.40,P=0.021;r=0.55,P<0.001）。141例5~30月龄婴幼儿的AACP与TAC-II双眼 视力有较强的相关性（r=0.88,P<0.001）,相关系数高于3~6岁儿童,Bland-Altman图显示90.8%的点 在一致性范围内,不同月龄间AACP与TAC-II视力均存在明显正相关（r=0.82~0.94,均P<0.05）,不 同月龄间AACP视力差异有统计学意义（H=32.02,P<0.001）,视力随月龄增长而逐渐递增。结论： AACP与TAC-II所得到的婴幼儿视力结果存在正相关,在低年龄婴幼儿中有更好的相关性和一致性。 AACP有望成为适合临床条栅视力评估及婴幼儿视力筛查的检查工具。     

Chart memory and visual acuity measurement

BACKGROUND: A small, but statistically significant, improvement has previously been demonstrated when retesting visual acuity within 24 hours. Because letter chart testing procedures are familiar to most adult patients, this improvement may be due to memory of the chart letter subset, rather than increased familiarity with the test procedure. Chart letter subset memory does not appear to have previously been measured directly. METHODS: A letter recognition task was used to measure chart letter subset memory for groups of routine clinical patients. Comparisons were made between assessments after a single acuity measurement and assessments at increasing intervals after a routine examination involving several references to the same letter chart for both eyes. RESULTS: The recognition score for the 'one-minute-after a single acuity measurement group' was an average of 2.5 letters (range 0.7 to 4.7). Low levels of chart letter subset memory were found to persist for 10 days. CONCLUSION: The chart letter subset memory found is consistent with enhanced acuity scores that occur on retesting. Scores appear likely to have a greater chance of enhancement for a second eye measurement when it follows immediately after the first. Similarly, scores at the end of a full examination may be enhanced by memory that is accumulated during multiple measurements for both eyes using the same chart. Chart memory may be acquired when acuity is measured frequently in monitoring the progress of disease. Chart memory, or its loss over time, may contribute to measurement imprecision and associated expansion of the confidence limits for significant change in acuity.     

激光干涉条纹视力预测白内障术后视力的观察

对52只白内障眼在手术前作激光干涉条纹视力检查,并与术后矫正视力对照,二者基本符合占51.8%、大致符合占13.4%,共65.2%,提示用激光干涉条纹视力检查法预测白内障的术后矫正视力有一定临床意义,建议将激光干涉条纹视力检查作为白内障术前视网膜功能检查方法之一。     

A Novel Computerized Visual Acuity Test for Children

Purpose

To investigate the efficacy of a computerized visual acuity test, the SNU visual acuity test for children.

Methods

Fifty-six children, ranging from 1 to 5 years of age, were included. In a dark room, children gazed at and followed a circular dot with 50% contrast moving at a fixed velocity of 10 pixels/sec on a computer monitor. Eye movement was captured using a charge coupled device camera and was expressed as coordinates on a graph. Movements of the eye and dot were superimposed on a graph and analyzed. Minimum visualized dot diameters were compared to the Teller visual acuity.

Results

Ten eyes (8.9%) of six children failed to perform the Teller visual acuity test, and two eyes (1.8%) of one patient failed to perform the SNU visual acuity test. The observed Teller visual acuity and SNU visual acuity were significantly correlated (p < 0.001). Visual angle degrees converted from the Teller visual acuity and SNU visual acuity were also significantly correlated (p < 0.001).

Conclusion

The SNU visual acuity using moving targets correlated well with Teller visual acuity and was more applicable than the Teller acuity test. Therefore, the SNU visual acuity test has potential clinical applications for children.     

A new specialized visual acuity chart for amblyopic children aged 3-5 years old:development and its clinical applications

AIM: To introduce a new specialized visual acuity chart for amblyopic children aged 3-5 years old and its clinical applications.METHODS:The new visual acuity chart and notations were designed based on Weber-Fechner law. The optotypes were red against a white background and were specially shaped four basic geometric symbols:circle, square, triangle,and cross. A regular geometric progression of the optotype sizes and distribution was employed to arrange in 14 lines. The progression rate of the optotype size between two lines was 1.2589 and the testing distance was 3m. Visual acuity score could be recorded as logMAR notation or decimal notation. Age-stratified diagnostic criteria for amblyopia established by consensus statement on diagnosis of amblyopia (2011) among members of the Strabismus and Pediatric Ophthalmology Group, Ophthalmology Society, Chinese Medical Association (SPOGOSCMA) were illustrated in the new visual acuity chart.RESULTS: When assessing visual acuity in children aged 3-5 years old, this new visual acuity chart that consists of four symmetrical shapes (triangle, square, cross, and circle) overcame an inability to recognize the letters of the alphabet and difficulties in designating the direction of black abstract symbols such as the tumbling ‘E’ or Landolt ‘C’, which the subjects were prone to lose interest in. The visual acuity score may be recorded in different notations:decimal acuity and logMAR. These two notations can be easily converted each other in the new eye chart. The measurements of this new chart not only showed a significant correlation and a good consistency with the international standard logarithmic visual acuity chart (r=0.932, P<0.01), but also indicated a high test-retest reliability (89% of retest scores were within 0.1logMAR units of the initial test score).CONCLUSION: The results of this study support the validity and reliability of distance visual acuity measurements using the new eye chart in children aged 3 to 5 years over a wide range of visual acuities, and the new eye chart is great for early detection of amblyopia. It can be applied in various clinical settings.