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1.
李太东 《中华眼视光学与视觉科学杂志》2013,15(10):597-600
目的探讨液晶视力表测量精度与显示屏点距的关系。方法 采用标准对照研究方法,调查常用显示屏相关参数,与新标准对数视力表国家标准(GB11533-2011)的视标大小及允许误差进行推算、对比研究。结果 液晶视力表在亮度、幅宽、白度、照明方面完全符合(GB11533-2011)要求;在液晶显示精度方面,0.27 mm点距的显示屏可准确测试远视力≤5.0视力;0.1245 mm点距显示屏可准确测试远视力≤5.2视力;点距0.077 mm的显示屏准确测试远视力≤5.3视力。结论 选择合适点距和测试距离可使液晶视力表测试结果更精确。 相似文献
2.
ETDRS对数视力表在儿童视力检查中的可重复性分析 总被引:1,自引:0,他引:1
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. 相似文献
3.
目的:分析智能视力表投影仪在视力检查中的可重复性及其与传统视力表测量结果的比较。方法:系列病例研究。收集2022年1月4—22日在首都医科大学附属北京同仁医院就诊的眼部不适患者60例(120眼)。先通过智能视力表投影仪(LSJ-IVAC-6000A)对患者进行3次视力检测,并采用组内相关系数(ICC)评价3次测量结果之间的可重复性;再用传统灯箱的国家标准视力表测量1次,并分别采用ICC和Bland-Altman图表法分析智能视力表投影仪与传统视力表检测结果的一致性。结果:同一受检者右眼、左眼使用智能视力表投影仪测量3次的ICC值分别为0.830和0.868,双眼的ICC值均>0.8(P<0.001);同一受检者右眼、左眼使用智能视力表投影仪和传统灯箱的国家标准视力表测量的ICC值分别为0.846和0.873,双眼的ICC值均>0.8(P<0.001)。右眼、左眼使用智能视力表投影仪和传统灯箱的国家标准视力表测量差值的95%一致性界限分别为-0.25~0.20和-0.24~0.17。结论:智能视力表投影仪的可重复性较好,与传统灯箱的国家标准视力表的测量结果相比一致性较强,应用于临床工作中可提高视力筛查的效率并节省人力和物力。 相似文献
4.
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) 相似文献
5.
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。 相似文献
6.
两种视力表检查89位学龄前儿童视力的对比研究 总被引:1,自引:0,他引:1
目的比较学龄前儿童Lea Symbols与Tumbling E两种视力表的检测率、单眼视力值.建立3。4周岁儿童正常的视力值。方法招募温州市区29—53月龄的89名学龄前儿童,入选标准是身体一般情况良好。智力发育正常,除屈光不正外无其他眼病。以随机顺序用两种视力表检查儿童单眼视力,用间插的logMAR记分方法记录结果。招募23名成人志愿者,分别用两种视力表检查单眼视力.获得两者之间的换算关系。结果成人44眼Lea Symbols的平均视力比Tumbling E高0.02logMAR。89名儿童Lea Symbols视力表的检测率为88%.而Tumbling E视力表的检测率为65%,统计学分析两者差异有显著性(P〈0.01)。60位儿童中115眼能同时配合查Lea Symbols与Tumbling E,Lea Symbols的平均视力为0.17±0.09.Tumbling E的平均视力为0.25±0.09.两者作配对t检验差异具有显著性(P〈0.01)。两种视力表视力相关性高(r=-0.73,P〈0.01),两种视力表视力差值不随视力水平的改变而变化(P=-0.60)。正常屈光状态下儿童Lea Symbols 平均视力0.16±0.07(120眼)。Tumbling E的平均视力0123±0.07(91眼)。结论Lea Symbols视力表和Tumbling E视力表是测量视力可靠且有效的方法.检查4周岁以下儿童的视力时首选Lea Symbol视力表。与Tumbling E视力表相比,Lea Symbol视力表过高估计视力.原因可能在于两种视力表的不同设计以及儿童的认知水平差异。 相似文献
7.
目的 介绍一种新型的不同对比度视力表(ZyQv视力表,美国Baush&Lomb公司)及其临床应用.方法 以准分子激光原位角膜磨镶术治疗近视为例,使用ZyQv视力表测量54例近视患者手术前后不同对比度和不同照明环境下的视力,并与标准对数视力表的测量结果进行对比.结果 标准对数视力表测得的术前BCVA和术后不同时间点UCVA之间均无显著差异;使用ZyQv视力表发现:术后1周时,三组患者明暗环境中90%对比度视力均有显著下降,术后1月时均恢复至术前水平;三组患者明暗环境中10%对比度视力均于术后1周显著下降,其中低度近视组于术后1月恢复至术前水平,而中度和高度近视组在术后3月时仍低于术前水平(明环境中10%对比度视力除外).结论 ZyQv视力表操作便捷,在角膜屈光手术中可用于完善术前检查,综合评价术后视觉质量,动态观察术后视力恢复,协助临床实验和相关研究. 相似文献
8.
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。 相似文献
9.
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。 相似文献
10.
李刚 《中华眼视光学与视觉科学杂志》2013,15(10):593-596
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。 相似文献
11.
Srinivasa Varadharajan Krithica Srinivasan Brindha Kumaresan 《Ophthalmic & physiological optics》2009,29(5):549-556
Purpose: To design, construct and validate a new Tamil logMAR visual acuity chart based on current recommendations.
Methods: Ten Tamil letters of equal legibility were identified experimentally and were used in the chart. Two charts, one internally illuminated and one externally illuminated, were constructed for testing at 4 m distance. The repeatability of the two charts was tested. For validation, the two charts were compared with a standard English logMAR chart (ETDRS).
Results: When compared to the ETDRS chart, a difference of 0.06 ± 0.07 and 0.07 ± 0.07 logMAR was found for the internally and externally illuminated charts respectively. Limits of agreement between the internally illuminated Tamil logMAR chart and ETDRS chart were found to be (−0.08, 0.19), and (−0.07, 0.20) for the externally illuminated chart. The test – retest results showed a difference of 0.02 ± 0.04 and 0.02 ± 0.06 logMAR for the internally and externally illuminated charts respectively. Limits of agreement for repeated measurements for the internally illuminated Tamil logMAR chart were found to be (−0.06, 0.10), and (−0.10, 0.14) for the externally illuminated chart.
Conclusions: The newly constructed Tamil logMAR charts have good repeatability. The difference in visual acuity scores between the newly constructed Tamil logMAR chart and the standard English logMAR chart was within acceptable limits. This new chart can be used for measuring visual acuity in the literate Tamil population. 相似文献
Methods: Ten Tamil letters of equal legibility were identified experimentally and were used in the chart. Two charts, one internally illuminated and one externally illuminated, were constructed for testing at 4 m distance. The repeatability of the two charts was tested. For validation, the two charts were compared with a standard English logMAR chart (ETDRS).
Results: When compared to the ETDRS chart, a difference of 0.06 ± 0.07 and 0.07 ± 0.07 logMAR was found for the internally and externally illuminated charts respectively. Limits of agreement between the internally illuminated Tamil logMAR chart and ETDRS chart were found to be (−0.08, 0.19), and (−0.07, 0.20) for the externally illuminated chart. The test – retest results showed a difference of 0.02 ± 0.04 and 0.02 ± 0.06 logMAR for the internally and externally illuminated charts respectively. Limits of agreement for repeated measurements for the internally illuminated Tamil logMAR chart were found to be (−0.06, 0.10), and (−0.10, 0.14) for the externally illuminated chart.
Conclusions: The newly constructed Tamil logMAR charts have good repeatability. The difference in visual acuity scores between the newly constructed Tamil logMAR chart and the standard English logMAR chart was within acceptable limits. This new chart can be used for measuring visual acuity in the literate Tamil population. 相似文献
12.
A comparison of visual acuity measured by ETDRS chart and Standard Logarithmic Visual Acuity chart among outpatients
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AIM:To compare the results of visual acuity(VA)measured by Early Treatment Diabetic Retinopathy Study(ETDRS)chart,5 m Standard Logarithm Visual Acuity(5 SL)chart,and 2.5 m Standard Logarithm Visual Acuity(2.5 SL)chart in outpatients of age 12-80 y.METHODS:Each patient(totally 2000 outpatients)had both eyes tested with ETDRS chart at 4 m,5 SL chart at 5 m,and 2.5 SL chart at 2.5 m in random order.The VA values of outpatients were categorized by ages.VA values were expressed by log MAR recording method.RESULTS:The mean VA results of ETDRS charts,5 SL,and 2.5 SL chart were 0.52±0.28,0.50±0.30,and 0.46±0.28 log MAR,respectively.There was a statistically significant difference in the three eye charts in the whole group(P<0.001).For all subjects,the correlation of VA tested with three charts was statistically significant(Spearman correlation coefficient=0.944,0.937,0.946,all P<0.001).Bland–Altman analysis shows the 95%limits of agreement between the 5 SL and 2.5 SL chart were-0.182 to 0.210,-0.139 to 0.251,and-0.151 to 0.235 log MAR,respectively.CONCLUSION:The agreement between the three eye charts is not high.The VA measured by 5 SL chart is slightly better than that by ETDRS chart and 5 SL chart would be a suitable alternative when ETDRS chart are not available in the clinical situation.The VA measured by 2.5 SL chart is about 0.5 line better than VA tested with ETDRS chart,which may overestimate VA. 相似文献
13.
The development of a "reduced logMAR" visual acuity chart for use in routine clinical practice
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BACKGROUND/AIMS: The advantages of logMAR acuity data over the Snellen fraction are well known, and yet existing logMAR charts have not been adopted into routine ophthalmic clinical use. As this may be due in part to the time required for a logMAR measurement, this study was performed to determine whether an abbreviated logMAR chart design could combine the advantages of existing charts with a clinically acceptable measurement time. METHODS: The test-retest variability, agreement (with the gold standard), and time taken for "single letter" (interpolated) acuity measurements taken using three prototype "reduced logMAR" (RLM) charts and the Snellen chart were compared with those of the ETDRS chart which acted as the gold standard. The Snellen chart was also scored with the more familiar "line assignment" method. The subjects undergoing these measurements were drawn from a typical clinical outpatient population exhibiting a range of acuities. RESULTS: The RLM A prototype chart achieved a test-retest variability of +/-0.24 logMAR compared with +/-0.18 for the ETDRS chart. Test-retest variability for the Snellen chart was +/-0.24 logMAR using clinically prohibitive "single letter" scoring increasing to +/-0.33 with the more usual "line assignment" method. All charts produced acuity data which agreed well with those of the ETDRS chart. "Single letter" acuity measurements using the prototype RLM charts were completed in approximately half the time of those taken using the ETDRS and Snellen charts. The duration of a Snellen "line assignment" measurement was not evaluated. CONCLUSION: The RLM A chart offers an acceptable level of test-retest variability when compared with the gold standard ETDRS chart, while reducing the measurement time by half. Also, by allowing a faster, less variable acuity measurement than the Snellen chart, the RLM A chart can bring the benefits of logMAR acuity to routine clinical practice. 相似文献
14.
Development of a clinically feasible logMAR alternative to the Snellen chart: performance of the "compact reduced logMAR" visual acuity chart in amblyopic children
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BACKGROUND/AIM: The "compact reduced logMAR" (cRLM) chart is being developed as a logMAR alternative to the Snellen chart. It is closer spaced and has fewer letters per line than conventional logMAR charts. Information regarding the performance of such a chart in amblyopes and children is therefore required. This study aimed to investigate the performance of the cRLM chart in amblyopic children. METHODS: Timed test and retest measurements using two versions of each chart design were obtained on the amblyopic eye of 43 children. Using the methods of Bland and Altman the agreement, test-retest variability (95% confidence limits for agreement, TRV) and test time of the cRLM and the current clinical standard Snellen chart were compared to the gold standard ETDRS logMAR chart. RESULTS: No systematic bias between chart designs was found. For line assignment scoring the respective TRVs were 0.20 logMAR, 0.20 logMAR, and 0.30 logMAR. Single letter scoring TRVs were cRLM (95% CL 0.17) logMAR, ETDRS (95% CL 0.14) logMAR, and Snellen (95% CL 0.29) logMAR. Median testing times were ETDRS 60 seconds, cRLM 40 seconds, Snellen 30 seconds. CONCLUSION: The sensitivity to change of the cRLM equalled or approached that of the gold standard ETDRS and was at least 50% better than that of Snellen. This enhanced sensitivity to change was at the cost of only a 10 second time penalty compared to Snellen. The cRLM chart was approximately half the width of the ETDRS chart. The cRLM chart may represent a clinically acceptable compromise between the desire to obtain logMAR acuities of reasonable and known sensitivity to change, chart size, and testing time. 相似文献
15.
Bourne RR Rosser DA Sukudom P Dineen B Laidlaw DA Johnson GJ Murdoch IE 《Eye (London, England)》2003,17(6):754-758
AIMS: This study aimed to evaluate a new chart designed to improve the collection of visual acuity data in population-based surveys. The Reduced logMAR E chart (RLME) employs three letters per line, 'tumbling E' optotypes, and conforms to accepted contemporary design principles. METHODS: The performance of the chart was assessed within a population-based glaucoma survey in Thailand. Performance indices were test-retest variability (TRV) and agreement with acuity data measured using the ETDRS logMAR chart which acted as the 'gold standard'. RESULTS: The 95% confidence limits for TRV of RLME acuity data were +/-0.15 logMAR. This figure is consistent with published data on the TRV of acuities measured using five-letter-per-line logMAR charts. The mean difference between RLME and ETDRS acuity data was 0.00 logMAR (95% confidence intervals of +/-0.05 logMAR) indicating that RLME acuities agreed well with those of the ETDRS chart. The chart and its method of use was readily accepted by the local ancillary staff who required only minimal training before acuity measurement could be delegated to them. CONCLUSIONS: The study demonstrated that the RLME chart is capable of accurate and repeatable acuity measurements. Certain aspects of the design of the RLME chart may be particularly pertinent to the measurement of vision in population-based surveys. 相似文献
16.
Purpose
The aim of the study was to compare the performance of two different COMPlog computerised, single letter scoring, visual acuity (VA) measurements against gold standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart measurements in patients with age-related macular degeneration (AMD). One computerised algorithm presented five and the other presented three letters per line; both computerised algorithms utilised half, rather than the full-letter width spacing standard on ETDRS charts that might induce crowding, fixation problems, increased test–retest variability (TRV), and bias.Methods
Fifty patients with AMD (mean age 83 years) underwent timed test and retest VA measurements using ETDRS charts and COMPlog five (C5) and three (C3) letters per line computerised VA measurement algorithms. All tests utilised single-letter scoring methodology. Bland and Altman methods were employed. Performance was measured in terms of bias, TRV, and test time.Results
The C5 and C3 scores showed no bias compared with the ETDRS chart measurements. C5 measurements had equal TRV to the ETDRS chart (±0.13 logMAR) with similar median test times (105 and 96 s, respectively). C3 measurements were slightly more variable (TRV ±0.17 logMAR), but 30 s quicker than ETDRS chart measurements.Conclusions
The closer letter spacing employed in COMPlog testing algorithms appears to have no adverse effect on VA measurements compared with the gold standard ETDRS chart in patients with AMD. The three letter per line testing algorithm facilitates faster testing but with a two letter increase in TRV. 相似文献17.
Clinical usefulness of the baby vision test in young children and its correlation with the Snellen chart
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AIM: To investigate the efficacy of a new visual acuity (VA) screening method, the baby vision test for young children.
METHODS: A total 105 eyes of 65 children aged 2-8y were included in the study. Acuity testing was conducted using a standardized recognition acuity chart (Snellen visual chart: at 3 m) and the baby vision model assessment. The baby vision device includes a screen, a near infrared camera and a computer. Children were seated at a measured distance of 33-40 cm from a display for testing. VA was estimated according to the highest resolution the children could follow. Decimal VA data were converted to logarithm of the minimum angle of resolution (logMAR) for statistical analysis. The VA results for each child were recorded and analyzed for consistency.
RESULTS: The mean VA measured using the Snellen visual chart was 0.62±0.32, and that assessed using the baby vision test was 0.66±0.27. The 95% limit of agreement was -0.609 to 0.695, with 95.2% (100/105) plots within the 95% limits of agreement. VA values of the baby vision test were significantly correlated with those of the Snellen chart (R=0.274, P=0.005).
CONCLUSION: The baby vision test can be used as a relatively reliable method for estimating VA in young children. This new acuity assessment might be a valid predictor of optotype-measured acuity later in preverbal children. 相似文献
18.
Aims
The impression exists that picture acuity scores may overestimate function when subjects are switched to letter charts. This has not been systematically investigated. The aims of this study were to validate both printed crowded Kay picture (pCKP) and computerised CKP (cCKP) logMAR test acuity measurements against gold standard ETDRS letter chart scores.Methods
A total of 30 adult subjects with various ophthalmic disease and 40 amblyopic children underwent test and re-test visual acuity measurements using the ETDRS chart, the pCKP logMAR test, and the cCKP acuity scores taken, using the COMPlog visual acuity measurement system. Bland and Altman methods were employed.Results
Computerised and printed Kay picture acuity scores agreed well. Both Kay picture test measurements were systematically biased when compared with ETDRS chart measurements. No significant proportional bias was found. The test retest variability (TRV) of all three tests was found to be similar between ±0.14 and 0.16 logMAR in both groups.Conclusions
All three tests were similarly replicable and computerised Kay pictures appear to be a valid alternative to hard copy Kay pictures. Kay picture acuity measurements were systematically biased when compared with the gold standard ETDRS. Measurement error means that differences of up to 0.16 logMAR may be observed in clinically stable patients when re-measured using the same technique. A combination of TRV and systematic bias can however lead to differences of up to 0.40 logMAR in stable amblyopic patients when switched from CKPs to ETDRS chart acuity measurements. 相似文献19.
AIM:To introduce a new near-vision chart for children aged 3-5 years old and its clinical applications.METHODS:The new near-vision chart which combined the Bailey-Lovie layout with a newly devised set of symmetry symbols was designed based on Weber-Fechner law. It consists of 15 rows of symmetry symbols, corresponding to a visual acuity range from 1.3 to 0.1 logMAR. The optotypes were red against a white background and were specially shaped four basic geometric symbols:circle, square, triangle,and cross, which matched the preschool children's cognitive level. A regular geometric progression of the optotype sizes and distribution was employed to arrange in 15 lines. The progression rate of the optotype size between two lines was 1.2589 and two smaller groups of optotypes ranging from 0.7 to -0.1 logMAR were included for repetitive testing. A near visual acuity was recorded in logMAR or decimal, and the testing distance was 25 cm.RESULTS:This new near-vision chart with pediatric acuity test optotypes which consists of 4 different symbols (triangle, square, cross, and circle) met the national and international eye chart design guidelines. When performing the near visual acuity assessment in preschoolers (3-5 years old). It 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. Near vision may be recorded in different notations:decimal acuity and logMAR. These two notations can be easily converted each other in the new near-vision chart. The measurements of this new chart not only showed a significant correlation and a good consistency with the Chinese national standard logarithmic near-vision chart (r=0.932, P<0.01), but also indicated good test-retest reliability (89% of retest scores were within 0.1 logMAR units of the initial test score) and a high response rate.CONCLUSION:The results of this study support the validity and reliability of near visual acuity measurements using the new near-vision chart in children aged 3-5y over a wide range of visual acuities, and the new eye chart was especially suitable for the detection of amblyopia risk factors and low vision examination in children (3-5y of age). It can be applied in routine clinical practice. 相似文献