论双眼视力与单眼视力的不统一性

目的 针对临床中部分患者单眼视力正常,而双眼视力下降的现象,探讨双眼视力与单眼视力的不同含义,并分析其引起双眼视力下降及双眼视功能异常的原因和机制.方法 分别检查患者的单眼、双眼裸眼远、近视力及矫正视力,眼位,眼球运动,眼前节和眼底,电脑加综合验光仪验光,同视机、三棱镜、立体视功能检查.结果 15例单眼视力正常而双眼视力低下患者中,3例患者为中高度远视,6例患者为间歇性外斜视;另6例患者存在轻度屈光参差.根据其不同原因给予矫正后,双眼视力得到明显提高.结论 临床工作中除常规检查单眼视力外,还应重视双眼视力及双眼视功能的检查,并给予相应治疗.     

屈光性弱视与屈光参差性弱视对比敏感度变化的比较

目的：观察屈光不正性弱视与屈光参差性弱视的对比敏感度改变的差异性。方法：对30例（56只眼）屈光不正性和26例（26只眼）屈光参差性弱视的视觉对比敏感度（CS）进行测定。结果：在明视状态下中、重屈光参差性弱视在中频（6c/d)区CS下降幅度大于屈光不正性弱视（P＜0.05);夜视条件下,两弱视组所有空间频率的CS均无显著性差异。结论：中、重度的屈光参差性弱视的视觉质量比屈光不正性弱视低下。     

单眼弱视患者非弱视眼对比敏感度函数的研究

本文用稳态ＶＥＰ的方法对斜视性及屈光参差性单眼弱视患者非弱视眼的对比敏感度函数（ＣＳＦｓ）进行了研究。结果表明，两种弱视患者非弱视眼的ＣＳＦ均较正常儿童的ＣＳＦ低平，表现为中、高空间频率区ＣＳＦ的明显受损，提示两种弱视患者的非弱视眼亦非正常，可能有Ｘ通道的受损。其原因可能与双眼视及两眼之间的相互作用有关。     

单眼慢性阿托品化对视觉发育关键期内大鼠视觉发育的影响

目的：探讨单眼阿托品化对视觉发育关键期内大鼠视觉发育的影响。
　　方法：将20只出生14 d的健康SD大鼠随机分为实验组和对照组,每组10只,均选取左眼为干预眼,右眼作为对照眼。实验组1%硫酸阿托品眼用凝胶点左眼,每日3次,右眼生理盐水点眼,每日3次。对照组大鼠给予生理盐水点双眼,每日3次。在点眼前及点眼后的7,14,21,28 d分别行闪光视觉诱发电位检查及带状检影法测量屈光度。在点药后28d,从实验组和对照组中各随机选取3只大鼠,检测c-fos mRNA的表达;后在实验组与对照组中再各随机选取3只大鼠,放入暗室2d后给予2h正常饲养环境光线刺激,再次检测c-fos mRNA的表达。
　　结果：实验组点药后14d产生屈光参差,两眼相差3.9D(P<0.05),实验组大鼠左眼F-VEP的P1波在点药后21 d峰时值延长为88.9±1.889ms,与右眼相比差异有统计学意义(P<0.05)。点药后28d,实验组大鼠左侧视皮层中c-fos mRNA表达较右侧视皮层高,但无显著差异;但在放入暗室2d后再给予2h光线刺激,实验组大鼠左侧视皮层中c-fos mRNA表达为右侧视皮层的5倍,有显著统计学差异(P<0.05)。
　　结论：在视觉发育关键期内大鼠的单眼慢性阿托品化可形成屈光参差,使视传导发生延迟,阻碍了视皮层的正常发育。大鼠的单眼慢性阿托品化可作为制作屈光参差的研究模型。     

左旋多巴改善屈光参差性弱视视功能的远期效果

目的：观察“思利巴”的有效成分左旋多巴改善屈光参差性弱视单字视力、拥挤视力、对比敏感度、立体视的远期效果。方法：61例5．5－15岁难治性屈光参差性弱视患者，被随机分成实验组和对照组，两组均用传统治疗，实验组加服思利巴3个月，观察两组实验前，实验第1个月、第2个月、第3个月、第6个月、第9个月末的单字视力、拥挤视力、对比敏感度变化及实验前和实验第9个月的立体视变化。结果：（1）服药组弱视眼：（1）单字视力：第1个月、第2个月逐渐提高且变化有显著性。（2）拥挤视力：第1个月提高有显著性。（3）对比敏感度：服药后1个月中低空间频率改善有显著性，高空间频率无变化。以上结果均保持到实验结果。（2）立体视变化无显著性。（3）服药组优势眼及对照组比较，各项指标无变化。结论：（1）服药2个月后，可改善难治性屈光参差性弱视眼的单字视力，服药1个月可改善拥挤视力。（2）思利巴可改善中低空间频率的对比敏感度。（3）服用思利巴3个月对立体视及优势眼无影响。     

白内障摘出单焦点人工晶状体植入术后存在屈光参差者的视功能观察

目的评价单眼视概念在老年人白内障手术中应用的可行性。方法选取双眼白内障摘出单焦点人工晶状体植入术后符合标准的病例42例(84眼),按照屈光参差度数的不同分为3组,检查其远近视力及对比敏感度、立体视锐度,并人为加镜形成双眼平衡全矫状态加以对照,数据进行统计学分析。结果第1组(屈光参差<1.00 D):视力、低频段对比敏感度和立体视,与平衡全矫状态者对比,二者无明显差异;第2组(屈光参差1.00 D～1.75 D):与平衡全矫状态者对比,视力相近,但对比敏感度和立体视则差于平衡全矫状态,尤其是在高频段差异明显;第3组(屈光参差≥2.00D):视力、对比敏感度及立体视均明显差于平衡全矫状态者。随着屈光参差度数的增加,对比敏感度和立体视功能均是下降的。结论对于术后不需进行精细工作或长时间近距离阅读,也不从事夜间驾驶的老年白内障患者,可以在设计手术时运用单眼视方式,使术后既可视远又可视近,方便患者,提高生活质量。     

单眼视力下降对双眼对比敏感度的影响

目的 研究单眼视力下降时双眼对比敏感度（CS）的变化规律,初步探讨单眼视力下降对双眼视功能及双眼相互作用的影响,并且探讨其在司法鉴定中的运用价值。方法 实验研究。于2016年3月至2017年8月选择司法鉴定科学研究院志愿者46例（男24例,女22例）。单眼矫正视力或裸眼视力均达4.9以上,主导眼前放置试验透镜,用插片法诱导实验性单眼视力不同程度下降。分别测试其左眼、右眼及双眼的视力、CS,计算对比敏感度双眼总和比（BSR）。数据进行球形检验、方差分析及秩和检验。结果 单眼视力下降可引起双眼视力一定程度下降,但是双眼视力仍优于单眼。当视力下降至轻度损害水平时,全频段正常倒“U”形CS曲线形态已破坏,且相较低空间频率而言,中、高空间频率时CS下降程度更为明显;在高频区且两眼视力均正常时,出现最大的BSR,为1.48。当单眼视力逐渐下降时,出现双眼平均及抑制（BSR<1）。提示双眼相互作用的形式存在一定程度的容忍性及空间依赖性。结论 单眼视力下降对双眼CS、双眼相互作用的形式及程度具有一定程度的影响。运用双眼CS检测,能够反映单眼视力的损害程度,具有临床及司法鉴定运用价值。     

知觉学习改善屈光参差性弱视视功能的临床观察

目的探讨知觉学习训练在改善青少年及成人屈光参差性弱视患者视功能方面的效果。方法前瞻性自身对照研究。共纳入18例青少年和成年单眼屈光参差性弱视患者,弱视眼在截止空间频率下进行对比度检测任务的训练,对侧相对健眼作为对照。患者随访3～6个月。分别观察患者训练前后的最佳矫正视力和对比度阈值改变,立体视改变以及试验组训练前后视觉诱发电位改变。数据进行t检验、相关性分析。结果弱视眼与相对健眼相比,其在训练前后的视力改变,截止空间频率下的对比度阈值改变,以及所有空间频率下的对比度阈值改变差异均有统计学意义（t=2.731,P<0.05;t=5.108,P<0.01;t=3.700,P<0.01）,弱视眼及对侧眼在训练前后潜伏期变化,振幅变化差异均无统计学意义,并且18例中有8例立体视得到改善。12例患者随访3个月,弱视眼视力平均保持了99.3%,对侧眼视力改善平均保持了50%。结论知觉学习能改善青少年及成年屈光参差性弱视患者的视功能,可用于治疗大龄弱视。     

屈光参差对对比敏感度的影响

目的探讨屈光参差的程度对对比敏感度的影响。方法随机选择双眼屈光参差但矫正视力≥1．0的患者38例（76眼），平均年龄（29．61±8．78）岁（19～53岁），等效球镜值为（-6.57±3．64）D（0．25- -14．50D），双眼度数相差（-3．67±2．40）D（-1．50- -12．00D）。按屈光参差的程度将患者分成两组：A组44眼。双眼度数相差≥3．00D；B组32眼，双眼度数相差〈3．00D。使用Stereo Optical公司生产的OPTEC6500型眩光对比敏感度测试系统分别测试患者在最佳矫正视力下左右眼的对比敏感度。应用SPSS11．5统计软件对结果进行配对比较的秩和检验。结果A组患者屈光度高的一眼较另一眼在中高频空间频率的对比敏感度下降，在空间频率为6．0c／d、12．0c／d和18．0c／d时，低屈光度眼与高屈光度眼的对比敏感度差值分别为6．54、12．04和6．27．P值分别为0．017、0．001和0．006．差异有显著性；而在低空间频率（1．5c／d和3．0c／d），双眼的对比敏感度差值分别为3．54和5．41，P值分别为0．266和0．254，双眼间的对比敏感度差异无显著性。B组患者左右眼的对比敏感度在各个空间频率（1．5c／d、3．0c／d、6．0c／d、12．0c／d和18．0c／d）中低屈光度眼与高屈光度眼的对比敏感度差值分别为-1．24、5．75、3．00、2.32和3．00，差异均无显著性．P值分别为0．824、0．327、0．789、0．419和0．062。结论3．00D以上的屈光参差影响中高频空间频率的对比敏感度，3．00D以下的屈光参差不对对比敏感度产生明显影响。     

实验性屈光参差对双眼视功能的影响

目的 :探讨实验性屈光参差对健康成人双眼视功能的影响。方法 :对双眼视功能正常的大学生志愿者 32人采用在单眼前加不同度数正负球镜的方法 ,诱导单纯近视性 ( 1D , 2D , 3D)及单纯远视性 (-1D ,- 2D ,- 3D)屈光参差 ,测定诱导屈光参差后的视力、立体视敏度及Worth四点融像功能。结果 :随着屈光参差程度的增加 ,单纯“近视眼”的远视力逐渐下降 ,单纯“远视眼”的远视力几乎不下降。立体视敏度随着屈光参差度数的增加而下降 (t检验 ,P <0 .0 5 ) ,相同程度的单纯远视性屈光参差比单纯近视性屈光参差立体视敏度下降更明显 (t检验 ,P <0 .0 5 )。Worth四点定性试验证实了诱导屈光参差后双眼单视功能下降 (χ2 检验 ,P <0 .0 5 ) ,并有黄斑抑制的发生 ,Worth四点定量试验表明抑制区视角度数随着屈光参差程度的增加而增加 (t检验 ,P <0 .0 5 )。结论 :实验性屈光参差可引起成人双眼视功能异常 ,未矫治的屈光参差对儿童双眼视功能潜在性影响还需要进一步研究     

Predicting binocular visual field sensitivity from monocular visual field results

PURPOSE: To compare methods of predicting binocular visual field sensitivity of patients with glaucoma from monocular visual field data. METHODS: Monocular and binocular visual fields were obtained for 111 patients with varying degrees of glaucomatous damage in one or both eyes, using the Humphrey 30-2 full-threshold procedure. Four binocular sensitivity prediction models were evaluated: BEST EYE, predictions based on individual values for the most sensitive eye, defined by mean deviation (MD); AVERAGE EYE, predictions based on the average sensitivity between eyes at each visual field location; BEST LOCATION, predictions based on the highest sensitivity between eyes at each visual field location; and BINOCUIAR SUMMATION, predictions based on binocular summation of sensitivity between eyes at each location. Differences between actual and predicted binocular sensitivities were calculated for each model. RESULTS: The average difference between predicted and actual binocular sensitivities was close to zero for the BINOCULAR SUMMATION and BEST LOCATION models, with 95% of all predictions being within +/-3 dB of actual binocular sensitivities. The best eye (MD) prediction had an average error of 1.5 dB (95% confidence limits [CL], +/-3.7 dB). The average eye prediction was the poorest, with an average error of 3.7 dB (95% CL, +/-4.6 dB). CONCLUSIONS: The BINOCULAR SUMMATION and BEST LOCATION models provided better predictions of binocular visual field sensitivity than the other two models, with a statistically significant difference in performance. The small difference in performance between the BINOCULAR SUMMATION and BEST LOCATION models was not statistically significant. For evaluations of functional visual field influences on task performance, daily activities, and related quality-of-life issues, either the BINOCULAR SUMMATION or BEST LOCATION model provides good estimates of binocular visual field sensitivity.     

Variability of monocular visual acuity during binocular viewing.

Two patients observed changes in the visual acuity of one eye when both eyes were viewing simultaneously in certain directions of gaze. While viewing targets presented during the Turville Infinity Balance (TIB) test, the acuity of the affected or amblyopic eye improved when the nonamblyopic eye was covered and binocular vision suspended. The vision of the amblyopic eye was also improved when an appropriate prism was held in front of either eye. The direction of the prism base was based upon the interrelations of horizontal, vertical, and cyclotorsional anisophoria and the amount of prism was the minimum necessary to improve the vision in the amblyopic eye and neutralize vertical fixation disparity. The correlation of variable monocular acuity, stereopsis, and fixation disparity with oculomotor balance is recorded and discussed.     

Preference for binocular concordant visual input in early postnatal development remains despite prior monocular deprivation

Short daily periods of binocular vision, if concordant and continuous, have been shown to outweigh or protect against much longer daily periods of monocular deprivation to allow the development of normal visual acuity in both eyes of kittens. The greater weight placed on binocular visual input could arise because of an inherent bias for binocular input within the visual pathway at all times during development (Binocular model), or else from a more passive process that follows from its match to a highly binocular template at the time mixed daily visual input began (Template model). To distinguish between the predictions of these two models, kittens were monocularly deprived from normal eye-opening until either 4, 5, or 6 weeks of age at which time they received mixed daily visual input for 4 weeks. According to the Template model, the preferred input for these animals would be monocular exposure (ME) because of its match to the monocular template produced by a period of preceding monocular deprivation. However, instead of short daily period of ME offsetting much longer periods of binocular exposure (BE) to perpetuate the dire effects of the prior deprivation, short daily periods of BE promoted significant recovery of vision in the deprived eye. The fit to the Binocular model implies the existence of a robust substrate for binocular vision that is highly resistant to disruption and which could form the substrate for binocular approaches to treatment of amblyopia.     

Refractive-error changes in kitten eyes produced by chronic on-channel blockade

The dependence of the emmetropization process on retinal ON-channel activity was examined in developing kittens by making regular intravitreal injections of D,L-2-amino-4-phosphonobutyric acid (APB). In comparison to sham-injected control eyes, the APB-treated eyes had shorter axial lengths and were more hyperopic. Since chronic atropinization did not alter the development of the APB-induced hyperopia, these anomalous refractive errors are not the result of altered accommodative function. The axial hyperopia observed in the APB-treated eyes indicates that the mechanisms responsible for normal axial elongation are dependent to some extent on ON-channel activity and that, even in the presence of a clear retinal image, OFF-channel activity, by itself, is not sufficient to regulate the normal emmetropization process.     

Functional visual outcomes of cataract extraction in monocular versus binocular patients

PURPOSE: To determine the change in functional vision that occurs with cataract surgery in a group of monocular patients compared with a group of binocularly sighted control subjects. DESIGN: A retrospective case-control study. METHODS: Study subjects comprised 100 functionally monocular patients who underwent cataract surgery at the Jules Stein Eye Institute between 1996 and 2002. Control subjects were 100 binocularly sighted patients, matched to study subjects by age, sex, and timing of surgery. A single ophthalmologist performed all of the operations using an ultrasonic phacoemulsification technique. Best-corrected visual acuity (BCVA) was measured before and after surgery using a conventional visual acuity monitor. Self-reported visual function was assessed before and after surgery using the Visual Function 14 (VF-14) questionnaire. Paired t tests were used to report statistical significance. RESULTS: The monocular group had significantly worse mean BCVA than the binocular group before and after surgery, but the improvement experienced by the two groups was statistically indistinguishable (P =.913). Mean global VF-14 score was significantly worse for the monocular than the binocular group before and after surgery, but the monocular group experienced a significantly greater improvement (P =.00164) in VF-14 following surgery (20.4 points for the monocular group vs 10.1 points for the binocular group). CONCLUSIONS: Monocular patients report twice as much improvement in functional vision as binocular patients despite similar BCVA gains. This may be because monocular patients had cataract surgery on their better-seeing eye, whereas binocular patients typically had surgery on their poorer-seeing eye.     

The development of monocular and binocular VEP acuity

The development of monocular and binocular grating acuity was measured in 87 infants, 2-52 weeks of age, using the sweep VEP technique. Average monocular and binocular acuity growth functions were nearly identical, with a small (less than 0.2 octaves) binocular acuity superiority occurring only under 6 months. Interocular acuity differences were small (averaging less than 1/4 octave, unsigned, with a 95% confidence interval of less than +/- 0.6 octaves) and were not significant at any age. These characteristics make the sweep VEP technique a potentially sensitive tool for the detection of monocular visual losses in the early stages of amblyopia.     

单眼视野损伤程度对青光眼患者双眼视野的影响

目的：探讨单眼视野丢失严重程度对原发性闭角型青光眼、原发性开角型青光眼和正常眼压性青光眼患者双眼视野缺损的影响。

方法：根据双眼单眼视野缺损的阶段,将120例青光眼患者和30例健康参与者分为正常、早期、中度或重度四个阶段。通过整合视野和Esterman双眼视野评估确定双眼视野。在组内和组间比较单眼和双眼视野参数。

结果：对于一只眼睛处于正常或早期阶段而另一只眼睛处于严重阶段的患者,双眼综合视野平均偏差分别为-2.8±1.1、-5.5±1.9dB,以及Esterman的平均得分分别为99.1%±1.7%和95.6%±4.7%。当双眼发展为中度或重度损伤(中度/中度,中度/重度或重度/重度)时,双眼综合视野平均偏差低于-6dB,中度/中度和中度/严重损伤组Esterman的平均得分分别为94.2%±6.0%、94.3%±4.9%,但当双眼处于重度损伤阶段时,Esterman的平均得分迅速从大于90%下降到68.4%±26.3%。

结论：如果一只眼睛处于正常或早期阶段,双眼视野可以保持相对完整。当双眼进展到中度或重度阶段时,通过双眼综合视野平均偏差测量的双眼视野缺损是显著的,并且仅当双眼进入严重阶段时才检测到显著的Esterman双眼视野缺损。     

Permanent alterations in muscarinic receptors and pupil size produced by chronic atropinization in kittens

Chronic mydriasis was induced in six kittens (four monocular, two binocular) and two adult cats (both monocular) by the daily topical application of atropine. Both the kittens and the adult cats were atropinized for a 13-week period with the treatment regimen beginning at the time of eye opening for the kittens. Pupil size measurements, obtained 1 year after the atropinization were discontinued, revealed that, although the pupils of the adult cats were normal, the pupils of the kittens' treated eyes were consistently smaller than pupils in control eyes. The status of the muscarinic receptors in the kittens' irides was investigated using 3H-QNB binding assays. In comparison with iris muscle homogenates from the control eyes, those from the treated eyes demonstrated an eightfold increase in the number of receptor binding sites. The results indicate that pupil size can be altered permanently by chronic mydriasis initiated early in the life of a kitten and that the permanent change in pupil size may result, in part, from a type of permanent supersensitivity response in the muscle following chronic blockade of muscarinic transmission by atropine.