斜视弱视治疗中应注意的几个问题

近年来国内斜视、弱视的诊断与治疗水平不断提高。但在斜视、弱视治疗中尚存在一些需要进一步澄清和强调的问题,如斜视手术的目的是什么、斜视手术时机如何选择、如何规范弱视的诊断与治疗等。有些问题在一些眼科医师中还存在着比较模糊的认识。本文就相关问题进行阐述,并藉此与眼科同道探讨。     

斜视性弱视发病机制的研究进展

随着脑科学的蓬勃发展,弱视神经机制的研究进入到一个崭新阶段。研究证实:发育早期异常视觉经验可影响皮层神经元的空间特性,弱视视功能损害涉及多个脑区并与皮层神经元空间特性的异常密切相关,弱视是视觉神经通路多方位、多层次损害的综合。在此我们对斜视性弱视发病机制的研究进展作一综述。     

弱视治愈行斜视矫正术后视力追踪观察

目的了解斜视性弱视及斜视性屈光参差性弱视患者在弱视治愈,行斜视矫正术后,弱视眼视力的变化.方法对1992～1997年在我院弱视治愈后行斜视手术矫正患者103例进行视力追踪观察.结果弱视治愈后行斜视手术后原弱视眼有50.49%存在不同程度视力减退,并且与开始治疗时弱视程度有关,即弱视开始治疗时的视力越低越易出现视力减退.结论弱视治愈行斜视术后的弱视眼,应密切监护,直到视力、眼位均巩固在正常范围为止.     

单眼弱视的临床分析

目的　探讨单眼弱视的临床特点。方法　对 96例单眼弱视进行追踪观察 ,对弱视类型、程度、注视性质与疗效的关系进行统计分析 ,并观察其立体视变化。结果　单眼弱视中屈光参差性弱视占 66 67% ,斜视性弱视占 33 33%。斜视合并屈光参差性弱视患者基本治愈率仅 50 % ,单眼弱视中重度弱视较多 ,占 33 33% ,立体视恢复正常者 55 2 1 % ,均为屈光参差性弱视。结论　单眼弱视患者中常见斜视性弱视和屈光参差性弱视两种临床类型 ,其中以斜视伴有屈光参差的弱视治疗效果最差 ,而斜视对患者的立体视损害最严重     

我国弱视与斜视防治10年进展

在中华医学会眼科学分会的领导下,我国弱视、斜视防治工作近10年来有了长足的进步,医疗技术及科研水平逐年提高,专业队伍迅速成长,专业书刊相继出版,定期举行的全国弱视、斜视学术会议,制订了弱视与斜视的病种分类及疗效标准,对促进我国眼外肌领域学术研究水平的发展和提高,发挥了重要作用。目前,我国儿童弱视、斜视防治网已基本形成,多数省市已正式成立弱视、斜视防治组或中心,有些医学院校及儿童医院已开设了小儿眼科,各地妇幼保健机构相继设置了儿童眼保健科室,为及时有效地防治儿童弱视与斜视,保护并促进儿童视觉功能的正常发育,提供了…     

宁夏平罗县学龄前儿童斜视弱视普查

弱视和斜视是危害儿童视力和立体视觉的常见眼病[1] ,其防治的关键是早期筛选和治疗。为了解我县学龄前儿童斜视、弱视发病情况 ,以利早期开展斜视、弱视的防治工作 ,我们于 2 0 0 0年 7～ 10月对县城 2 5 6 9名 3～ 6 .5岁儿童进行斜视、弱视普查 ,现报告如下。1　对象与方法1.1　对象　选择县城全部幼儿园及学前班的 2 6 0 8名学生 ,实查 2 5 6 9名 ,年龄 3～ 6 .5岁 ,其中男 1335例 ,女 12 34例 ,受检率为 98.5 % .1.2　视力与斜视测定　采用灯箱式国际标准视力表测视力。视力 <0 .9列为第 2轮筛选对象。指定 2名眼科医师对全体受检学生…     

近年我国弱视,斜视临床和科研工作的新进展

中华眼科学会全国儿童斜视弱视防治学组自1984年成立以来,曾先后三次召开学术交流会以推动学科情报的交流.为使眼科学界的同道一览眼肌学科学述发展近况,现以最近的全国第三届弱视斜视学术交流会论文为依据,综述我国近年弱视、斜视方面的临床诊断、治疗和基础理论研究工作的进展情况.     

斜视性弱视多焦视觉诱发电位的研究

目的 研究斜视性弱视患者多焦视觉诱发电位(mfVEP)的特征性变化,探讨弱视的发病机制,对弱视预后的判断给予临床指导.方法 收集斜视性(内斜)弱视患者30例、正常人30例,分为斜视性弱视组、对侧眼组和正常对照组3组,采用多焦电生理系统进行图形mfVEP检测,分析潜伏期与振幅密度.结果 6个离心度上弱视组反应振幅密度较对侧组和正常组均显著降低.弱视组及对侧组的鼻侧视网膜反应振幅密度均低于颞侧视网膜,潜伏期延长.斜视性弱视患者斜视度与弱视眼视力及mfVEP波形异常程度之间均无明显相关性.结论 斜视性弱视患者mfVEP表明弱视患者的视皮层与视觉传导通路均存在损害,mfVEP检查可为弱视的诊断、治疗及预后判断提供客观依据.     

左旋多巴对14例猫斜视性弱视模型的实验研究

目的：观察左旋多巴对猫弱视眼模型的作用，以探讨弱视的发病机理。方法：对14只猫斜视性弱视模型，分20mg/kg 40mg/kg左旋多巴及安慰剂灌胃给药，观察猫的图形视觉诱发电位。结果：左旋多巴能一定程度地缩短猫斜视性弱视眼的P1波峰灌时及提高P1波幅值。结论：用左旋多巴对猫斜视性弱视模型灌胃给药12周，能一定程度地改善其弱视眼的传导和感觉功能。     

斜视性弱视手术后视功能恢复情况的短期疗效研究

目的:了解斜视手术后3mo内对斜视性弱视眼的视功能恢复情况的研究。方法:对2006-06/2008-03在我院行斜视手术的合并有弱视的98例患儿,年龄3.5～15(平均7)岁,其中共同性外斜76例,共同性内斜22例,手术前后用国际标准视力表进行视力的检测、同视机进行双眼视功能检查以及睫状肌麻痹下屈光状态的检查,采用自身对照的方法,将术后1wk;1,3mo的弱视眼视力、双眼视功能以及屈光状态与术前对比,统计学采用两因素方差分析(two-way ANOVA)。结果:术后1wk弱视眼视力较术前提高有显著性差异(P<0.05),双眼融合范围较术前提高有显著性差异。立体视觉的产生在术后1mo较术前有显著性差异。术后1mo的屈光状态与术前相比无统计学差异。结论:斜视性弱视经过斜视手术后可以迅速改善斜视性弱视眼的注视性质,使弱视眼视力和双眼视功能在术后1wk即可得到有效的提高,屈光状态无明显改变,眼位的正常是恢复视功能的关键。     

Increased drift in amblyopic eyes.

Reports are conflicting on the presence of increased drift in amblyopic eyes. Furthermore, the individual effects of either amblyopia or strabismus alone on ocular drift have not been systematically investigated. We therefore used a photoelectric method to record horizontal eye position during monocular and binocular fixation in patients having amblyopia without strabismus, intermittent strabismus, or constant strabismus amblyopia. Our principal finding was increased drift amplitude (up to 3.5 degree) and velocity (up to 3.0 degrees per second) in amblyopic eyes during monocular fixation. While increased drift was found 75% of the time in amblyopia without strabismus and 50% of the time in constant strabismus amblyopia, it was found only 20% of the time in intermittent strabismus. Amblyopic drift could be either error-producing or error-correcting in nature. Increased drift was not present during monocular fixation with the dominant eye or during binocular fixation in any of our 16 patients. We therefore conclude that amblyopia and not strabismus is a necessary condition for the presence of markedly increased fixational drift. Increased drift amplitude but not velocity may adversely affect visual acuity in the amblyopic eye.     

Fixational eye movements in amblyopia and strabismus

Horizontal eye position was monitored using a photoelectric method during monocular and binocular fixation in four patients having amblyopia without strabismus, thirteen patients having constant strabismus with amblyopia, and five patients having intermittent strabismus. Four abnormalities of fixation were found: increased drift, saccadic intrusions, manifest nystagmus, and latent nystagmus. Increased drift was related to the presence of amblyopia, while saccadic intrusions and nystagmus were related to the presence of strabismus. Understanding dynamic aspects of oculomotor control can provide insight into clinical assessment of fixation in amblyopia and strabismus.     

Dynamic vergence eye movements in strabismus and amblyopia: asymmetric vergence.

This report investigates line-of-sight asymmetric disparity vergence in patients having either intermittent strabismus, constant strabismus with amblyopia, or amblyopia without strabismus. We find an absence of disparity vergence in all patients with strabismus and in some with amblyopia only. Accommodative vergence and saccades place the dominant eye on the targets moving in depth. These accommodative vergence responses have normal dynamic characteristics, thus indicating a properly functioning vergence motor system. We purpose there is a higher-level central defect in which incoming information of one eye is suppressed, so that the disparity vergence system is rendered inoperable.     

Rapid, high-accuracy detection of strabismus and amblyopia using the pediatric vision scanner

Purpose. The Pediatric Vision Scanner (PVS) detects strabismus by identifying ocular fixation in both eyes simultaneously. This study was undertaken to assess the ability of the PVS to identify patients with amblyopia or strabismus, particularly anisometropic amblyopia with no measurable strabismus. Methods. The PVS test, administered from 40 cm and requiring 2.5 seconds of attention, generated a binocularity score (BIN, 0%-100%). We tested 154 patients and 48 controls between the ages of 2 and 18 years. BIN scores of amblyopic children and controls were measured, and 21 children received sequential PVS measurements to detect any changes in BIN resulting from amblyopia treatment. Results. With the pass/refer threshold set at BIN 60%, sensitivity and specificity were 96% for the detection of amblyopia or strabismus. Assuming a 5% prevalence of amblyopia or strabismus, the inferred positive and negative predictive values of the PVS were 56% and 100%, respectively. Fixation accuracy was significantly reduced in amblyopic eyes. In anisometropic amblyopia patients treated successfully, the BIN improved to 100%. Conclusions. The PVS identified children with amblyopia or strabismus with high sensitivity and specificity, while successful treatment restored normal BIN scores in amblyopic patients without strabismus. The results support the hypothesis that the PVS detects strabismus and amblyopia directly. Future strategies for screening by nonspecialists may thus be based on diagnostic detection of amblyopia and strabismus rather than the estimation of risk factors, allowing for rapid, accurate identification of children with amblyopia early in life when it is most amenable to treatment.     

A new test of contour integration deficits in patients with a history of disrupted binocular experience during visual development

Previous studies have suggested that the integration of orientation information across space is impaired in amblyopia. We developed a method for quantifying orientation-domain processing using a test format that is suitable for clinical application. The test comprises a graded series of cards where each card includes a closed path (contour) of high contrast Gabor signals embedded in a random background of Gabor signals. Contour visibility in both normals and patients with histories of abnormal binocular vision depends jointly on the spacing of elements on the contour as well as background element density. Strabismic amblyopes show significant degradation of performance compared to normals. Small but significant losses in sensitivity were also observed in a group of non-amblyopic strabismus patients. Threshold measurements made with contrast reducing diffusers indicated that the amblyopic loss is not due to the reduced contrast sensitivity of the amblyopic eye. An abnormal pattern of long-range connectivity between spatial filters or a loss of such connectivity appears to be the primary source of contour integration deficits in amblyopia and strabismus.     

The Effect of Amblyopia Therapy on Ocular Alignment

PURPOSE: We sought to describe the change in ocular alignment at 2 years after treatment of amblyopia in children younger than 7 years of age at enrollment. METHODS: A randomized clinical trial of patching versus atropine for 6 months followed by standard clinical care for 18 months was conducted in 357 children with anisometropic, strabismic, or combined amblyopia (20/40-20/100) whose ages ranged from 3 to younger than 7 years at enrollment. Ocular alignment was evaluated at enrollment and after 2 years of follow-up. RESULTS: At enrollment when tested at distance fixation, 161 (45%) children were orthotropic, 91 (25%) had a microtropia (1-8 Delta), and 105 (29%) had a heterotropia >8 Delta. Of the 161 patients with no strabismus, similar proportions of patients initially assigned to the patching and atropine groups developed new strabismus by 2 years (18% vs. 16%, P = 0.84). Of these cases of new strabismus, only 2 patients in the patching group and 3 patients in the atropine group developed a deviation that was greater than 8 Delta. Microtropia at enrollment progressed to a deviation greater than 8 Delta with similar frequency in both treatment groups (13% vs. 15%, P = 1.00). Of the 105 patients with strabismus greater than 8 Delta at enrollment, 13% of those in the patching group and 16% of those in the atropine group improved to orthotropia without strabismus surgery. Strabismus surgery was performed in 32 patients during the 2-year study period. CONCLUSIONS: Patients who had amblyopia treatment with patching or atropine for 6 months followed by standard clinical care were found to have similar rates of deterioration and improvement of ocular alignment. When parents begin amblyopia treatment for children without strabismus, they should be warned of the possibility of development of strabismus, although it is most often a small angle deviation. Strabismus resolved after amblyopia therapy in some cases.     

Listing's law in strabismus and amblyopia: a preliminary report

We investigated whether Listing's law applies in patients with diminished or no stereopsis due to strabismus or amblyopia. Eye movements of normal subjects and patients with strabismus and/or amblyopia were recorded during monocular and binocular fixation; from these data the shape and relative orientation of displacement planes were calculated. In normal subjects, monocular or binocular fixation did not influence the thickness and relative orientation of displacement planes. No differences were found between normals and the patient with amblyopia due to anisometropia. In one patient with strabismus but without amblyopia, the orientation of displacement planes depended on the fixation conditions; a coupling between horizontal vergence effort and plane orientation was observed. Patients with amblyopia and strabismus showed abnormally shaped and/or abnormally orientated displacement planes, which depended on the fixation conditions. Differences between both eyes in the shape of the planes were also observed. These results show that normal Listing behavior can be present in subjects with diminished stereopsis. They also show that normal stereopsis does not necessarily mean normal Listing behavior, suggesting that Listing's law is mainly a result of motor strategy.     

屈光参差性弱视与斜视性弱视临床疗效的比较

目的:分析比较屈光参差性与斜视性弱视的治疗效果。方法:前瞻性研究。2018-07/2020-01在我院门诊确诊的并首次接受治疗的单眼弱视患者46例,平均年龄9±3岁,其中男26例,女20例,按照临床诊断分为斜视性弱视组(无屈光不正),共23例,平均年龄9±3岁,其中男12例,女11例。以及屈光参差性弱视组,共23例,平均年龄9±3岁,其中男14例,女9例。对两组患者采用遮盖及精细训练治疗弱视,于治疗前及治疗后采用国际标准视力表检测视力、用Titmus图谱行立体视锐度的检测。比较两组患者经弱视治疗前后最佳矫正视力及立体视恢复的差异。结果:治疗前两组患者弱视眼的最佳矫正视力无差异(t=-0.475,P>0.05),但斜视性弱视患者的立体视功能明显低于屈光参差性弱视患者(t=-3.919,P<0.001);通过2mo的治疗,两组患者最佳矫正视力提高值有明显差异(t=-2.946,P<0.01),而两组患者立体视提高值无差异(t=1.305,P>0.05);通过6mo的治疗,两组患者最佳矫正视力提高差值有明显差异(t=-2.353,P<0.05),两组患者立体视提高差值也有明显差异(t=2.218,P<0.05);但在6mo时斜视性弱视患者的立体视水平仍低于屈光参差性弱视患者(t=-2.760,P<0.01)。结论:治疗前视力相同的斜视性弱视与屈光参差性弱视,斜视性弱视患者的立体视功能损伤更重。通过治疗,屈光参差性弱视患者的视力恢复较快,而斜视性弱视患者的立体视功能恢复较快,但其立体视功能水平仍低于屈光参差性弱视患者。     

Listing's law in strabismus and amblyopia: a preliminary report

We investigated whether Listing's law applies in patients with diminished or no stereopsis due to strabismus or amblyopia. Eye movements of normal subjects and patients with strabismus and/or amblyopia were recorded during monocular and binocular fixation; from these data the shape and relative orientation of displacement planes were calculated. In normal subjects, monocular or binocular fixation did not influence the thickness and relative orientation of displacement planes. No differences were found between normals and the patient with amblyopia due to anisometropia. In one patient with strabismus but without amblyopia, the orientation of displacement planes depended on the fixation conditions; a coupling between horizontal vergence effort and plane orientation was observed. Patients with amblyopia and strabismus showed abnormally shaped and/or abnormally orientated displacement planes, which depended on the fixation conditions. Differences between both eyes in the shape of the planes were also observed. These results show that normal Listing behavior can be present in subjects with diminished stereopsis. They also show that normal stereopsis does not necessarily mean normal Listing behavior, suggesting that Listing's law is mainly a result of motor strategy.