不同程度近视性屈光参差患者双眼间调节参数的差异性分析

目的：探讨近视性屈光参差患者双眼间调节力差异与屈光参差程度间的关系。方法：横断面研究。收集2019年11月至2021年6月在山东第一医科大学附属青岛眼科医院就诊的近视患者123例（246眼），年龄8~21岁。根据双眼间等效球镜度（SE）差值分为屈光不正组（SE差值≤0.25D）29例、低度屈光参差组（1.00D≤SE差值<2.50D）62例及高度屈光参差组（SE差值≥2.50D）32例3组。所有患者符合双眼最佳矫正视力（BCVA）≥0.8且各项原始数据较为完善。使用综合验光仪测量3组患者的单眼调节幅度（AMP）、单、双眼负相对调节（NRA）、正相对调节（PRA）、调节反应（AR）及调节灵活度（AF）在睫状肌麻痹下验光后确定双眼间屈光度数，分析3组间双眼调节相关参数及单眼调节参数差差值（双眼间调节参数差值＝近视屈光度较高眼调节数值-近视屈光度较低眼调节数值）之间的差异。对3组间调节参数比较采用单因素方差分析；对屈光参差程度与双眼调节参数值及双眼间调节参数差值间的关系分析选择Spearman相关分析。结果：3组间双眼NRA、PRA、AR、AF值及单眼间NRA、AF差值比较差异均无统计学意义。3组AR差值分别为-0.03±0.25、0.20±0.30、0.26±0.36，差异有统计学意义（F=7.36，P<0.001）；3组PRA差值分别为0.04±0.27、0.34±0.72、0.66±0.63，差异有统计学意义（W=7.47，P<0.001）；3组AMP差值分别为0.41±0.86、-1.07±1.53、-1.02±2.18，差异有统计学意义（W=9.25，P<0.001）。事后多重比较显示，屈光不正组与低度屈光参差组和高度屈光参差的AR差值、PRA差值、AMP差值比较差异均有统计学意义（均P<0.05）。相关性分析显示，SE差值与AR差值、AMP差值存在低强度的正相关性（r=0.22，P=0.014；r=0.36，P<0.001）。结论：不同程度近视性屈光参差患者双眼间调节参数差值不同，且双眼间AR差值、AMP差值与双眼间屈光度差异程度存在一定相关性。     

飞秒激光制瓣LASIK术对近视性屈光参差患者调节功能的影响

目的：探讨飞秒激光制瓣LASIK术对屈光参差患者调节功能的影响。

方法：采用系列病例观察试验设计。收集行飞秒激光制瓣LASIK术的近视性屈光参差患者35例70眼,分别于术前和术后1、3mo进行随访观察,检测裸眼远视力、远用等效球镜度、双眼屈光度差值、单眼调节幅度、正负相对调节、调节滞后量。

结果：术后1、3mo的裸眼远视力明显提高,远用等效球镜度、双眼屈光度差值较术前明显降低; 术后3mo的单眼调节幅度和正相对调节较术前戴镜明显提高(P<0.05); 术前戴镜、术后1mo裸眼、术后3mo裸眼的负相对调节、调节滞后量差异无统计学意义(P>0.05)。

结论：飞秒激光制瓣LASIK术治疗近视性屈光参差是一种安全有效的术式,手术未对患者的调节功能产生不良影响,可能有助于恢复双眼协调一致的调节功能。     

低度近视性屈光参差不同矫正方式的调节功能研究

目的:研究分别采用单焦框架眼镜与角膜塑形镜矫正低度近视性屈光参差的儿童单眼及双眼调节的差异。方法:回顾性研究。收集2019-11/2020-04于我院眼科门诊就诊的低度近视性屈光参差(1.0D≤双眼等效球镜差<2.5D)儿童47例94眼,其中配戴框架眼镜者27例54眼作为A组,配戴角膜塑形镜者20例40眼作为B组。分别记录并比较两组患儿矫正1mo后的矫正视力及调节参数[调节反应(AR)、调节灵活度(AF)、调节幅度(AMP)]的差异。结果:两组患儿AR测量值均为正值,表现为调节滞后,A组患儿屈光高度眼调节滞后量显著高于屈光低度眼(0.63±0.21D vs 0.25±0.34D,P<0.001),但B组患儿双眼调节滞后量无差异(P=0.104),且两组患儿屈光高度眼与屈光低度眼单眼矫正视力和单眼AMP均无差异(P>0.05)。A组患儿双眼AR差值高于B组(0.38±0.36D vs 0.10±0.26D,P=0.005),双眼AF低于B组(8.22±1.15c/min vs 9.95±0.89c/min,P<0.001),但两组患儿双眼AMP无明显差异(P=0.280)。结论:低度近视性屈光参差儿童配戴角膜塑形镜比单焦框架眼镜矫正可获得更高的双眼调节灵活度,降低双眼调节反应差值,从而维持更协调的双眼调节功能。     

近视性屈光参差者双眼调节反应的研究

目的 研究在辐辏闭环情况下,近视性屈光参差者的调节滞后、调节反应/调节刺激曲线线性部分的斜率等眼动参数与正视者调节参数之间的差异的关系.方法 病例对照研究.40名志愿者(年龄18岁至31岁),其中正视者20人(等效球镜度+0.37至-0.25 D),20例近视性屈光参差者(双眼球镜度数差>2.50 D且<7.00 D,散光度数<1.00 D).在辐辏闭环状态下用WV-500双目自动验光仪测量1.00、2.00、3.00、4.00 D各调节刺激下的调节反应并得出AR/AS曲线及其线性部分的斜率.对正视组和屈光参差组的高低度数眼的客观调节滞后量、调节反应/调节刺激斜率、主观调节滞后量进行独立样本t检验.结果 在闭环条件下,屈光参差者高度数眼调节滞后量最大,其次是低度数眼、正视眼.在3.00和4.00 D刺激水平,屈光参差组高度数眼与正视眼调节滞后量之间差异有统计学意义(t=2.055,2.410;P<0.05).屈光参差者两眼之间AR/AS斜率差异无统计学意义(P>0.05),但屈光参差高度数眼的斜率低于正视眼的AR/AS斜率(t-2.550,P<0.05).结论 屈光参差者两眼调节反应不等,高度眼表现出更多的调节滞后.屈光参差者双眼在等量调节刺激下,表现为不等量的调节反应,高度数眼要产生相同的调节反应,需要更多的调节刺激.可能与调节中枢的控制增益不同有关,也可能与"睫状肌一晶状体"系统调节反应阈值较高有关.(中华眼科杂志,2009,45:612-615)     

Accommodation causes with-the-rule astigmatism in emmetropes.

PURPOSE: To measure the changes in astigmatism when bilateral emmetropes accommodate. METHODS: Bilateral emmetropes accommodative responses were measured with an improved photorefractometer PR-1100, which measured binocular refraction in all meridians simultaneously as a fixation target was shown in natural space. RESULTS: The accommodative responses in the vertical meridian are greater than those in the horizontal meridian. In the horizontal meridian, the accommodative responses are less than the accommodative stimulus. CONCLUSIONS: When accommodating the majority of bilateral emmetropes show with-the-rule astigmatism and lag of accommodation in the horizontal meridian.     

Ametropia in Down''s syndrome

Non-cycloplegic video-refraction and cycloplegic retinoscopy refraction results are reported for a Cambridge population of binocular, non-strabismic infants aged 7–9 months.
Method: The Cambridge vision screening programme detected high refractive errors by measuring the accommodative response to a 75 cm distance toy using the VPR-1 video-refractor. Of 4452 infants screened, the binocular mean refraction was −0.7 D, i.e. +0.62 D accommodative 'lag' or focus error (SD = ± 0.92 D). Seven percent had + 1.5 D refraction, i.e. + 2.8 D focus error or accommodative 'lag' in any one meridian. Of those followed up, refraction was also measured by cycloplegic retinoscopy (cycloRet) and VPR-1 (cyclo VPR) after 1 drop 1% cyclopentolate.
Results: Of the 223 infants who had large lags of accommodation + 2.8 D: (a) High hyperopia of + 3.5 D in any one meridian, by cyclo-Ret, was found in 173/223 (78%) of these infants. The mean cyclo-Ret spherical equivalent was + 3.8 ± 1.8 DS and unsigned astigmatism 0.8 ± 0.7 DC. The magnitude of the largest accommodative lag was significantly related to the cyclo-Ret most-positive-meridional power ( r = 0.4, P < 0.0001, n = 223). The majority orientation of the largest (non-cyclo-VPR) lag power was horizontal (WTR astigmatism). (b) The latest longitudinal refractive changes in this highly hyperopic group and also a control group will be described in terms of mean spherical equivalent, astigmatism and anisometropia.
Conclusion: The large lags of accommodation can reveal infants with highly hyperopic meridians. These infants may require early partial spectacle correction.
Acknowledgement: Supported by the Medical Research Council (Grant G7908507).     

青少年儿童近视性屈光参差双眼眼动参数的临床研究

目的：观察儿童和青少年近视性屈光参差患者双眼眼动参数,初步探讨儿童和青少年近视性屈光参差对眼动参数的影响。

方法：病例对照研究。选取2014-09/2016-05于重庆医科大学附属大学城医院就诊的7～14岁儿童及青少年82例,其中正视者(对照组)47例,近视性屈光参差者(试验组)35例,检测所有入选者的屈光度、5m和40cm隐斜、梯度性和计算性AC/A比值及调节功能\〖40cm的调节反应(FCC)、正负相对调节(NRA/PRA)、调节力(AMP)和调节灵敏度(AF)\〗。

结果：两组受检者5m和40cm隐斜度数、40cm FCC、PRA及AC/A比值差异均有统计学意义(P<0.05); AF、NRA、AMP与正常值最小值的差值差异均无统计学意义(P>0.05)。

结论：近视性屈光参差对儿童和青少年5m和40cm隐斜、40cm FCC、PRA及AC/A比值有显著影响。     

调节对近视性散光的影响

目的 探讨调节对近视性散光的可能影响及散光的变化对近距离工作的可能影响.方法 横断面研究.序贯选取近视性散光者87例(166眼存在散光),检查其屈光不正度、远矫正下近视力(DCNVA)、视近(眼前40 cm)状态下的散光修正度及视近散光修正后的近视力(ACNVA).视近状态下散光的修正采用交义柱镜.对视远与视近状态下的散光度、视远与视近状态下散光轴位、DCNVA与ACNVA 三对数据的差值进行正态性检验,若服从正态分布则采用配对t检验进行分析,若不服从则采用配对秩和检验.对视近状态下和视远状态下散光的差异量与残余散光度之间进行相关性分析.结果 视近与视远状态下散光度的差异具有统计学意义(Z=-5.32,P＜0.01),且视近时散光度呈增加的趋势;二者轴位的差异无统计学意义;DCNVA与ACNVA的差异具有统计学意义,且散光修正后视力有提高的趋势(Z=-5.74,P＜0.01).顺规、斜轴及低度散光(≤-1.00 D)者与总体趋势相一致,而逆规散光及散光度＞-1.00 D者不具有该趋势.结论 人眼各子午线的调节不均衡使调节时散光发生改变,不同程度地影响着近视力,从而影响近距离工作,这于顺规、斜轴及低度散光患者更为明显.     

角膜屈光手术对近视患者双眼视功能的影响

目的：:探究角膜屈光手术对近视患者双眼视功能的影响及临床意义。方法：:回顾性研究。选取2018年1月至2020年4月于长春爱尔眼科医院屈光手术中心行角膜屈光手术的患者82例（164眼）,年龄18~32（23.5±4.2）岁。术前等效球镜度（SE）为-8.38~-0.88（-4.75±1.69）D。根据双眼SE差值将患者...     

调节对近视性散光的影响

目的 探讨调节对近视性散光的可能影响及散光的变化对近距离工作的可能影响.方法 横断面研究.序贯选取近视性散光者87例(166眼存在散光),检查其屈光不正度、远矫正下近视力(DCNVA)、视近(眼前40 cm)状态下的散光修正度及视近散光修正后的近视力(ACNVA).视近状态下散光的修正采用交义柱镜.对视远与视近状态下的散光度、视远与视近状态下散光轴位、DCNVA与ACNVA 三对数据的差值进行正态性检验,若服从正态分布则采用配对t检验进行分析,若不服从则采用配对秩和检验.对视近状态下和视远状态下散光的差异量与残余散光度之间进行相关性分析.结果 视近与视远状态下散光度的差异具有统计学意义(Z=-5.32,P＜0.01),且视近时散光度呈增加的趋势;二者轴位的差异无统计学意义;DCNVA与ACNVA的差异具有统计学意义,且散光修正后视力有提高的趋势(Z=-5.74,P＜0.01).顺规、斜轴及低度散光(≤-1.00 D)者与总体趋势相一致,而逆规散光及散光度＞-1.00 D者不具有该趋势.结论 人眼各子午线的调节不均衡使调节时散光发生改变,不同程度地影响着近视力,从而影响近距离工作,这于顺规、斜轴及低度散光患者更为明显.     

近视性屈光参差主导眼的屈光状态及其调节功能

目的 研究近视性屈光参差主导眼与近视程度的关系以及主导眼与非主导眼调节功能分析,探讨屈光参差的成因及其发展原因。设计 回顾性病例系列。研究对象 8～35岁近视性屈光参差患者59例,根据屈光参差程度,将其分为低度屈光参差（1.00 D≤双眼等效球镜度差≤2.50 D）和高度屈光参差（双眼等效球镜度差>2.50 D）两组。方法 对各组别患者应用简化双手卡洞法测定双眼中的主导眼眼别。使用综合验光仪测定患者单、双眼正/负相对调节及其比值（PRA/NRA）。采用改良移近法及正负球镜翻转法分别测量单、双眼的调节幅度和调节灵活度。主要指标 主导眼眼别与屈光度大的眼别的相关性。单、双眼正/负相对调节及其比值（PRA/NRA）,单、双眼的调节幅度和调节灵活度。结果 低度屈光参差患者26例,主导眼为右眼者22例（84.5%）;主导眼平均屈光度为（-4.01±1.96）D,非主导眼为（-3.19±1.80）D,平均参差程度（1.76±0.21）D。主导眼屈光度高于非主导眼（z=-2.37,P=0.02）。高度屈光参差患者33例,主导眼为右眼者21例（63.6%）;主导眼平均屈光度为（-3.90±2.84）D,非主导眼平均屈光度为（-3.47±2.20）D,平均参差程度（3.40±0.81）D。主导眼与非主导眼屈光度比较无统计学差异（z=-0.57,P=0.57）。低度屈光参差组主导眼平均正相对调节为（-2.68±1.44）D,非主导眼为（-3.29±1.31）D,差异有统计学意义（z=-2.27,P=0.02）;高度屈光参差组主导眼平均正相对调节为（-3.14±1.84）D,非主导眼为（-4.10±1.59） D,差异有统计学意义（z=-3.54,P=0.00）。低度屈光参差组主导眼平均PRA/NRA绝对值为（1.15±0.58）,非主导眼为（1.36±0.52）,差异无统计学意义（z=-1.89,P=0.06）;高度屈光参差组主导眼平均PRA/NRA绝对值为（1.34±1.57）,非主导眼为（1.74±0.62）,差异有统计学意义（z=-3.03,P=0.00）。结论 低度近视性屈光参差患者主导眼屈光度较非主导眼高;不同程度的屈光参差患者主导眼PRA及PRA/NRA低于非主导眼。（眼科,2016, 25： 102-105）     

汉语发展性阅读障碍儿童调节功能与眼位的研究

目的 探讨汉语发展性阅读障碍儿童与正常儿童调节功能与眼位各参数的变化,明确影响汉语发展性阅读障碍儿童视觉效率的关键视觉因素.方法 病例对照研究.选取天津市12所小学五年级学生1458名.根据识字量和瑞文智力的测验结果,筛选出98名汉语发展性阅读障碍儿童为试验组,随机选取年龄、性别、瑞文智力与之匹配的98名正常儿童为对照...     

儿童非弱视性功能性视力低下的原因分析

分析儿童非弱视性功能性视力低下的形成原因。方法：系列病例研究。选取2015年6月至 2019年5月期间在濮阳市眼科医院就诊的非弱视性功能性视力低下儿童107例,年龄（8.3±1.9）岁。分别测量患者初始的最佳远近矫正视力（BCDVA、BCNVA）、单双眼调节灵敏度（MAF、BAF）、调节幅度（AMP）、调节反应（BCC）、正负相对调节（PRA、NRA）、远近水平隐斜（DLP、NLP）、调节性集合与调节比率（AC/A）、等效球镜度（SE）等数据。小数视力换算成5分记录法表达。用一元多重线性回归分析法研究训练前矫正视力与相关视功能参数自变量的关系。结果：双眼BCDVA均低于5.0者79例（73.8%）,单眼BCDVA低于5.0者28例（26.2%）;双眼BCNVA低于5.0者71例（66.4%）,单眼BCNVA低于5.0者22例（20.6%）。视功能检查显示所有视力低下眼的AMP均低于正常,诊断为集合不足和单纯性外隐斜者分别为59例和18例,分别占总例数的55.1%和16.8%,共占双眼BCDVA 均低于5.0例数的97.5%;单纯调节异常者27例,占总例数25.2%,占单眼BCDVA低于5.0例数的者 96.4%;BCDVA、BCNVA与AMP均呈正相关（r=0.563,P=0.035;r=0.587,P=0.029）,与NLP均呈负相关（r=-0.413,P=0.031;r=-0.409,P=0.030）,与BCC、PRA、NRA、DLP、AC/A、SE均无明显相关性（P均>0.05）。结论：①集合不足和单纯性外隐斜患者主要表现为双眼BCDVA均异常,单纯调节异常患者主要表现为单眼BCDVA异常。②儿童非弱视性功能性视力低下的形成和AMP、NLP异常有关,其中AMP异常是根本原因,NLP异常是继发原因。     

成年近视患者主视眼与调节因素间关系的研究

背景 主视眼是人类具有功能不对称行为的器官之一,它和非主视眼在很多方面的差异一直是基础研究和临床研究的热点,但基于成年近视患者调节功能方面的研究相对较少. 目的 研究成年近视患者主视眼和非主视眼与调节相关各因素之间的关系.方法 采用描述性系列病例观察的研究方法,纳入35例年龄为18～ 35岁、双眼屈光不正球镜度为-2.00 ～-10.00 DS、散光度≤1.50 DC且双眼屈光参差≤1.5 DS、最佳矫正视力(BCVA)≥1.0的单纯近视患者,采用卡洞法并结合拇指法判断主视眼的眼别,采用主观、客观综合验光法获得受检眼屈光不正的度数,用移近法测量单眼的调节幅度,以附加±0.50 D融合交叉柱镜(FCC)法测量受检眼的调节滞后情况,采用翻转法测量各眼的调节灵敏度. 结果 本组患者的主视眼与非主视眼调节幅度分别为(9.69 ±2.30)D和(9.60±2.37)D,调节灵敏度分别为(11.08±4.20) cpm和(10.63±4.60) cpm,调节滞后量分别为0和0.25 D,主视眼与非主视眼间的差异均无统计学意义(P=0.294、0.260、0.141).右眼为主视眼的患者双眼调节幅度分别为(9.48±2.29)D和(9.33±2.49)D,调节灵敏度分别为(10.50±4.70)cpm和(9.99±4.90) cpm,差异均无统计学意义(P=0.319、0.116),双眼调节滞后量的差异无统计学意义(P=0.590).左眼为主视眼的患者双眼调节幅度分别为(9.91±2.35)D和(9.88±2.26)D,调节灵敏度分别为(10.70±3.77) cpm和(11.25±4.27) cpm,差异均无统计学意义(P=0.749、0.295),双眼调节滞后量间的差异无统计学意义(P=0.238).结论 对于无或有较小屈光参差的成年近视患者,主视眼和非主视眼在调节幅度、调节灵敏度及调节准确性方面无差别.     

屈光参差儿童单眼配戴角膜塑形镜后调节功能的变化

目的：观察屈光参差儿童单眼配戴角膜塑形镜后双眼调节功能的变化,探讨调节在角膜塑形镜控制近视进展中的机制。

方法：前瞻性自身对照研究,对2016-09/2018-09在我院门诊就诊的屈光参差儿童单眼配戴角膜塑形镜的青少年22例44眼,将配戴角膜塑形镜的眼作为戴镜组,未作处理的另一眼作为未戴镜组。戴镜眼组22眼,等效球镜度-2.75±1.16D; 未戴镜眼组22眼,等效球镜度-0.10±0.32D。观察戴镜前和戴镜12mo后双眼屈光度差值、单眼调节幅度、调节灵敏度和调节反应的变化情况。

结果：戴镜组戴镜前的调节幅度和调节灵敏度低于未戴镜组(P<0.01),调节滞后高于未戴镜组(P<0.05)。戴镜组配戴12mo后的单眼调节幅度15.63±1.66D高于戴镜前11.25±3.15D(t=3.63,P<0.01),与未戴镜组无差异(t=0.75,P=0.46)。戴镜组配戴12mo后的单眼调节灵敏度14.63±1.58cyc/min高于戴镜前9.25±3.38cyc/min(t=2.83,P=0.01),与未戴镜组无差异(t=0.38,P=0.71)。戴镜组配戴12mo后的调节滞后0.62±0.29D较戴镜前1.35±0.26D减少(t=2.57,P=0.02),与未戴镜组无差异(t=0.61,P=0.55)。戴镜12mo后,未戴镜组的平均屈光度为-0.75±0.35D,戴镜组屈光度增长了-0.15±0.22D(t=2.90,P<0.01),未戴镜组屈光度增长了-0.65±0.39D(t=4.24,P<0.01),两组间屈光度的变化差值有差异(t=5.30,P<0.01)。未戴镜组12mo前后调节功能的变化无差异(P>0.05)。

结论：屈光参差儿童单眼配戴角膜塑形镜后戴镜眼的调节功能较戴镜前明显改善,且与对侧眼一致,戴镜眼的屈光状态更稳定,未戴镜眼逐渐呈现轻度近视屈光状态,但调节功能未出现明显变化。     

Binocular accommodative response with extended depth of focus under controlled convergences

Vergence and accommodation can be mismatched under virtual reality viewing conditions, and this mismatch has been thought to be one of the main causes of visual discomfort. The goal of this study was to investigate how optical conditions of the eyes affect accommodative responses to different convergence. Specifically, we hypothesized that extending the depth of focus (DoF) could weaken the control of the screen on accommodation, so that accommodation could be induced by convergence. To test this hypothesis, we extended the DoF using Zernike spherical aberrations (fourth and sixth orders) induced by a binocular adaptive optics (AO) vision simulator. Nine normal subjects between the ages of 21 and 34 (26 ± 5) years were recruited. Three optical conditions were generated: AO condition (aberration-free), monovision condition, and extended depth of focus (EDoF) condition. Binocular accommodative responses, along with binocular visual acuity and stereoacuity, were measured under all three optical conditions with varied binocular vergence levels. At 3 diopters of binocular convergence, the EDoF condition was the most efficient in inducing excessive accommodative response compared with the monovision condition and the AO condition. Visual acuity was impaired with EDoF as compared with the other two conditions. The average stereoscopic thresholds (at 0 vergence) under the EDoF condition were degraded compared with the AO condition but were superior to those of the monovision condition. Therefore, despite some compromise to visual performance, extending the DoF could allow for a more natural vergence–accommodation relationship, providing the potential for alleviating the vergence–accommodation conflict and associated visual fatigue symptoms in virtual reality.     

Accommodation demand and deprivation in kitten ocular development

The effects of accommodation demand and deprivation on the development of ocular optics was investigated in four groups of kittens (total n = 29). Group 1 consisted of five normal kittens; group 2 (nine kittens) had monocular radial keratotomy to induce relative hypermetropia and more accommodation demand as well as to impart interocular refractive differences (anisometropia); group 3 (eight kittens) received daily monocular atropine; and group 4 (seven kittens) had binocular radial keratotomy combined with daily monocular atropine. Regular examination provided documentation of ocular development from the first through the sixth months of life. Subsequently, the focal lengths of the crystalline lenses were determined in vitro. An apparent tendency for kitten eye pairs to grow toward isometropia, even when anisometropia had been induced early in life, was seen in those eyes in which the accommodative mechanism had been left intact (groups 1 and 2), but without accommodation anisometropia resulted (groups 3 and 4). There was relatively more elongation of the globe (3.08 +/- 0.22%) as well as shorter than normal focal lengths of the crystalline lens (-4.91 +/- 1.62% anterior, -2.78 +/- 1.54% posterior) in the eyes of the second group, and the eye pairs regained isometropia. In those eyes of the third and fourth groups that received atropine daily, there was relatively less elongation of the globe (-3.09 +/- 0.59% and -3.22 +/- 0.67%, respectively) and shorter crystalline lens focal lengths (-3.50 +/- 1.18% and -4.62 +/- 1.07% anterior, -2.64 +/- 1.02% and -1.59 +/- 0.62% posterior, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical method for measuring adaptation of tonic accommodation and vergence accommodation

Previous work indicates that tonic adapters of accommodation and vergence have indirect effects on accommodative vergence and vergence accommodation and that these crosslink responses interact with one another to produce clear and single vision. Clinical measurements of tonic accommodation, tonic vergence, vergence accommodation (CA/C ratio), and accommodative vergence (AC/A ratio) are therefore of value in determining possible binocular vision abnormalities. Currently, clinical methods are only available for measuring the tonic vergence (phoria) and the AC/A ratio. We have determined a fast and accurate method for evaluating both tonic accommodation (accommodative phoria) and vergence accommodation (CA/C ratio). In both procedures, the loop of accommodation was opened with a 0.2 cpd difference of Gaussian (DOG) target. This target was found to be incapable of stimulating any reflex accommodation, yet it is localized in space and can easily stimulate binocular fixation. Our results indicate that opening the loop of accommodation with a pinhole Maxwellian view or with a 0.2 cpd DOG produces similar response values for tonic accommodative aftereffects and vergence accommodation responses. The decay rate of tonic accommodative aftereffects as well as changes in the resting focus of accommodation caused by vergence accommodation (CA/C) can be measured clinically using dynamic retinoscopy in combination with the DOG target. Clinical values of the CA/C ratio obtained with these techniques were highly correlated (r = 0.92) with laboratory measures obtained with an objective infrared optometer and eye trac monitor.     

Spatially variant changes in lens power during ocular accommodation in a rhesus monkey eye

This study investigated the changes in ocular aberrations that occur over the entire lens equatorial diameter during accommodation in iridectomized rhesus monkey eyes to understand the nature of accommodative lenticular deformation. Accommodation was centrally stimulated to a range of different response amplitudes (0 D to approximately 11 D), and ocular aberrations were measured with a Shack-Hartmann wavefront sensor in both eyes of one previously iridectomized 10-year-old rhesus monkey. At the highest amplitude in the two eyes, aberrations were analyzed over entrance pupil diameters ranging from 3 to 8 mm in steps of 1 mm. Root mean square error of the total measured aberrations, excluding defocus, increased systematically with increasing accommodation from about 1 to 3.5 microns. Spherical aberration became systematically more negative, and vertical coma increased significantly in magnitude with accommodation. There was a strong accommodative change in power near the center of the lens and little change in power at the periphery. At the highest accommodative state, decreasing the analyzed entrance pupil diameter from 8 to 3 mm considerably reduced the wavefront error. The greater increase in optical power near the central region of the lens, combined with an accommodative pupillary miosis, would serve to maximize accommodative refractive change while maintaining acceptable image quality.     

屈光参差性弱视儿童双眼视觉状态

目的：分析屈光参差性弱视儿童的屈光状态、矫正视力情况及其与双眼视觉功能的关系。方法：横断面研究。收集2015年11月至2016年9月就诊于北京9家医院（分布于8个区县）的屈光参差性弱视儿童患者106例（106眼），年龄（6.2±5.4）岁。根据屈光参差危险因素将所有患者分为远视性屈光参差组（67例）、近视性屈光参差组（5例）、散光性屈光参差组（12例）、远视合并散光性屈光参差组（20例）及近视合并散光性屈光参差组（2例）。对所有患者行裸眼视力（UCVA）、矫正视力（BCVA）、屈光状态、远近立体视等检查。采用Pearson相关性分析双眼屈光参差的差值程度与高度屈光不正眼UCVA、BCVA及双眼视觉间的相关性，并分析双眼矫正视力差值程度与双眼视觉的相关性。采用单因素方差分析比较5组高度屈光不正眼BCVA及远近立体视情况。结果：屈光参差的差值程度与高度屈光不正眼UCVA和BCVA、远立体视、近立体视（即随机点立体视，包括立体视锐度、交叉立体视、非交叉立体视）均呈负相关（均P<0.05）；双眼矫正视力差值与远立体视、近立体视均呈负相关（均P<0.05）。5组间在高度屈光不正眼BCVA、远立体视、近立体视方面总体差异均有统计学意义（F=6.221、5.271、3.622、3.647、3.464，P<0.05），进一步两两比较显示高度屈光不正眼BCVA在近视性屈光参差组最好，然后依次为远视性屈光参差组、散光性屈光参差组、近视合并散光性屈光参差组以及远视合并散光性屈光参差组，组间差异均有统计学意义（均P<0.05）；远立体视在远视性屈光参差组最好，然后依次为近视性屈光参差组、散光性屈光参差组，组间差异均有统计学意义（均P<0.05），但远视合并散光性屈光参差组与近视合并散光性屈光参差组的远立体视差异无统计学意义；近立体视在近视性屈光参差组最好，然后依次为远视性屈光参差组、散光性屈光参差组、远视合并散光性屈光参差组以及近视合并散光性屈光参差组，组间差异均有统计学意义（均P<0.05）。结论：屈光参差性弱视儿童的屈光参差程度与视力、立体视功能相关，且立体视功能和双眼矫正视力差值也有相关性。不同类型屈光参差儿童立体视损害有所差异。