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1.
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。 相似文献
2.
视网膜视力测定是随着激光技术和人眼空间调制传递函数的深入研究而产生的新方法,它能反映屈光间质混浊情况下的视网膜功能。本文对视网膜视力仪进行了分类并阐述了其工作原理及使用方法,介绍了视网膜视力测定在白内障术前、视网膜病变、玻璃体疾病、角膜病变、弱视及屈光不正等病例中的应用,比较了不同视网膜视力仪在各类病变中的应用价值及其优缺点。 相似文献
3.
视网膜视力测定在眼科的应用 总被引:3,自引:0,他引:3
视网膜视力测定是随着激光技术和人眼空间调制传递函数的深入研究而产生的新方法,它能反映屈光间质混浊情况下的视网膜功能.本文对视网膜视力仪进行了分类并阐述了其工作原理及使用方法,介绍了视网膜视力测定在白内障术前、视网膜病变、玻璃体疾病、角膜病变、弱视及屈光不正等病例中的应用,比较了不同视网膜视力仪在各类病变中的应用价值及其优缺点. 相似文献
4.
目的 基于随机森林的算法探索影响单眼先天性白内障术后长期视力预后的因素。方法 回顾性队列研究。选择2008年1月至2021年12月住院手术的符合纳入和排除标准的单眼先天性白内障患儿,收集患儿的基线资料、手术资料和随访资料。利用随机森林算法分析影响末次随访时最佳矫正视力(BCVA)的因素,将末次随访时BCVA(logMAR)视为因变量,对因变量与自变量的关系采取两种方式拟合,模型一是将因变量视为连续性变量进行随机森林回归;模型二是将因变量视为二分类变量进行随机森林分类。选取平均准确度下降、平均基尼下降前五位的变量为重要性较高的变量。利用偏依赖关系图分析这些因素对术后视力影响的规律。结果 28例患儿纳入本研究,接受白内障摘除手术的中位年龄19.0(4.8~39.3)月龄,IOL植入的中位年龄35.5(30.0~44.0)月龄,白内障摘除联合一期IOL植入年龄中位数36.0(23.0~47.0)月龄;单纯白内障摘除手术的中位年龄5.0(3.5~15.0)月龄;二期IOL植入中位年龄35.0(33.0~42.0)月龄。斜视10(35.7%)例、眼球震颤1(3.6%)例;中位随访时间58.5(3... 相似文献
5.
视力性质分析在黄斑裂孔的应用 总被引:1,自引:0,他引:1
目的评价黄斑裂孔的视力性质。方法对20例全层黄斑裂孔和10例板层黄斑裂孔及10例囊样黄斑变性患者进行了中心暗点及固视性质检查。结果20例全层黄斑裂孔患者都存在中心绝对暗点,视力性质为中心外固视;而10例板层黄斑裂孔和10例囊样黄斑变性患者都无中心绝对暗点,视力性质为中心固视。结论全层黄斑裂孔的残留视力为中心外视力,视网膜上存在中心绝对暗点。 相似文献
6.
目的探讨阶梯渐进衍射型多焦人工晶状体植入治疗儿童单眼白内障的效果。方法 5例4~6岁单眼白内障儿童行白内障摘出联合多功能阶梯渐进衍射型多焦人工晶状体(Acry- 相似文献
7.
目的 研究单眼视(monovision,MV)原理在高度近视白内障患者中应用的效果.方法 高度近视伴白内障54例,行白内障超声乳化并单焦点人工晶状体植入术,应用单眼视原理,使术后主导眼(优势眼)形成正视,非主导眼保留-1.0D以上的近视,按屈光参差的程度分为3组,检查术后3个月双眼裸眼远视力、近视力、立体视及对比敏感度,并进行人为加镜形成双眼平衡全矫状态加以对照.最后进行视功能损害眼病患者生存质量量表问卷及满意率调查.结果 远视力及立体视3组比较差异无统计学意义(P>0.05),近视力比较3组单眼视矫正患者均明显优于完全矫正,差异有统计学意义(P<0.05).在100%对比度明视白背景下,第3组患者(屈光参差≥2.75D)单眼视矫正视力低于完全矫正,差异有统计学意义(P<0.05).明暗视时,红蓝背景下敏感度检查比较差异无统计学意义(P>0.05).术后问卷及满意率调查,3组患者间差异无统计学意义(P>0.05).结论 单眼视原理应用于高度近视伴白内障患者的屈光矫正,可有效提高患者远、近视力,非主导眼宜保留-1.5D以上的近视,具体情况还需根据患者个体差异而定.屈光参差≥2.75D的患者术后需注意夜间眩光现象. 相似文献
8.
资料患者男性,10岁,因双眼被激光手电照射后视力下降1 d来诊。该患儿在家中使用镜子反射观察激光手电被刺伤(图1),即感双眼视力下降,伴眼前黑影遮挡。眼科检查:右眼裸眼视力0.1,-1.25 DS矫正无提高;左眼裸眼视力0.25,最佳矫正视力(best-corrected visual acuity, BCVA)-0.75 DS/-0.50 DC×180°→0.4。双眼角膜透明,前房安静,瞳孔直径约2.5 mm,对光反射灵敏,晶状体透明。眼底示双侧视盘色淡红,边界清晰,右眼黄斑区见一椭圆形边界清楚的黄白色病灶(图2A),左眼黄斑区见小片状黄白色病灶(图2B)。 相似文献
9.
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。 相似文献
10.
目的 探讨超声乳化联合人工晶状体植入术中使用两种不同的单眼视设计治疗合并高度近视白内障患者的临床效果。方法 前瞻性非随机对照研究。选择2013年1月至2015年1月在我院行双侧超声乳化联合人工晶状体植入术的合并高度近视的白内障患者43例(86眼),根据不同的单眼视设计分成两组:A组非主导眼的目标屈光度为-1D;B组非主导眼的目标屈光度为-2D。随访至术后第3个月,记录双眼远、中、近距离视力,近立体视锐度,视觉质量评分,脱镜率及满意度评分。结果 术后第3个月,两组间的远、中距离视力差异均无统计学意义(均为P>0.05),B组的近视力优于A组(P<0.01)。两组间近立体视锐度差异无统计学意义(P>0.05)。两组的视远脱镜率均为100%,视近脱镜率分别为55%(A组)和87%(B组)。两组的视觉质量评价和满意度均达到了较好的水平,组间差异无统计学意义(P>0.05)。结论 -1D和-2D两种不同的人工晶状体眼单眼视设计,应用在合并高度近视的白内障患者中,都可以获得良好的临床效果,我们应当根据患者情况进行个性化选择。 相似文献
11.
William E. Scott MD Garry T. Drummond MD FRCS Ronald V. Keech MD Daniel J. Karr MD 《Clinical & experimental ophthalmology》1989,17(2):143-152
Sixty-two patients, 48 with a diagnosis of persistent hyperplastic primary vitreous (PHPV) and 14 with monocular congenital cataract (MCC) are reported. Nineteen patients with a diagnosis of PHPV and all patients with MCC received surgery with attempted visual rehabilitation.
Early age of surgery, prompt optical correction with contact lens and aggressive patching therapy are required for successful visual rehabilitation. Glaucoma, retinal or optic nerve pathology, surgery later than three months of age or combinations of these factors were associated with poor prognosis. Isolated microphthalmos was not correlated with poor prognosis.
Binocular fixation pattern was used to monitor patching therapy. Optokinetic nystagmus, visual evoked potentials or forced preferential looking were not employed.
Of the 33 patients who underwent surgery, 10 (30%) achieved good (> 20/50) visual acuity, 8 (24%) achieved fair (20/60 to 20/100) and 15 (46%) achieved poor vision.
In selected patients with the diagnosis of PHPV or MCC, visual rehabilitation can be achieved. 相似文献
Early age of surgery, prompt optical correction with contact lens and aggressive patching therapy are required for successful visual rehabilitation. Glaucoma, retinal or optic nerve pathology, surgery later than three months of age or combinations of these factors were associated with poor prognosis. Isolated microphthalmos was not correlated with poor prognosis.
Binocular fixation pattern was used to monitor patching therapy. Optokinetic nystagmus, visual evoked potentials or forced preferential looking were not employed.
Of the 33 patients who underwent surgery, 10 (30%) achieved good (> 20/50) visual acuity, 8 (24%) achieved fair (20/60 to 20/100) and 15 (46%) achieved poor vision.
In selected patients with the diagnosis of PHPV or MCC, visual rehabilitation can be achieved. 相似文献
12.
目的 分析优良视力正视眼低、中、高对比度视力与高阶像差的关系。方法 描述性研究。选择优良视力正视眼,在流明值为260背景亮度下,测量对比度为100%、25%、10%和5% 4种状态下的视力;同时采集瞳孔直径为3.11 mm和5.96 mm眼高阶像差。分析3.11、5.96 mm瞳孔直径眼高阶像差与不同对比度视力之间的相关性。采用线性回归分析,拟合出回归方程。结果 低对比度状态下视力的个体差异性更大。瞳孔直径为3.11 mm时,高阶像差均方根值(RMS)与不同对比度视力之间存在着线性相关关系(mini R2=0.1129)。结论 高阶像差对于对比度视力的影响特点是全频率。 相似文献
13.
Yasuyo Nishi Hajime Shinoda Atsuro Uchida Takashi Koto Hiroshi Mochimaru Norihiro Nagai Kazuo Tsubota Yoko Ozawa 《Acta ophthalmologica. Supplement》2013,91(5):e353-e357
Purpose: Patients with epiretinal membrane sometimes complain of impaired central visual function, despite good best corrected visual acuity (BCVA), as measured by visual acuity (VA) charts. Here, we evaluate early epiretinal membrane–induced changes in central VA. Methods: Subjects were 72 eyes of 36 patients with epiretinal membrane in only one eye and a BCVA in each eye better than 1.0, as measured by conventional Landolt C chart, at the Retina Division Clinic of the Department of Ophthalmology, Keio University Hospital, between December 2010 and November 2011. The conventional Landolt VA, functional VA (FVA) and contrast VA measurements were taken after a general eye examination. For the FVA, Landolt optotypes were sequentially displayed every 2 seconds, which size was changed according to the correctness of the answer. To exclude the influence of other diseases, a standard Schirmer test was performed to diagnose dry eye, and corneal and lens densities were evaluated. Results: Average BCVA measured by Landolt C chart was not changed between affected and unaffected fellow eyes. However, the affected eyes showed a poorer FVA score (0.21 ± 0.12, affected; 0.09 ± 0.12, fellow) and visual maintenance ratio (VMR) (0.90 ± 0.04, affected; 0.94 ± 0.04, fellow), measured by the FVA system, and contrast VA score (0.35 ± 0.11, affected; 0.25 ± 0.14, fellow) than fellow eyes. The FVA and contrast VA values were correlated with the presence of epiretinal membrane, but not with the presence of dry eye, cataract and corneal densities. Conclusion: FVA and contrast VA results reflected early changes in central visual function caused by epiretinal membrane, which were not detected by conventional Landolt BCVA. 相似文献
14.
The visual direction of a continuously presented monocular object is captured by the visual direction of a closely adjacent binocular object, which questions the reliability of nonius lines for measuring vergence. This was shown by Erkelens, C. J., and van Ee, R. (1997a,b) [Capture of the visual direction: An unexpected phenomenon in binocular vision. Vision Research, 37, 1193-1196; Capture of the visual direction of monocular objects by adjacent binocular objects. Vision Research, 37, 1735-1745] stimulating dynamic vergence by a counter phase oscillation of two square random-dot patterns (one to each eye) that contained a smaller central dot-free gap (of variable width) with a vertical monocular line oscillating in phase with the random-dot pattern of the respective eye; subjects adjusted the motion-amplitude of the line until it was perceived as (nearly) stationary. With a continuously presented monocular line, we replicated capture of visual direction provided the dot-free gap was narrow: the adjusted motion-amplitude of the line was similar as the motion-amplitude of the random-dot pattern, although large vergence errors occurred. However, when we flashed the line for 67 ms at the moments of maximal and minimal disparity of the vergence stimulus, we found that the adjusted motion-amplitude of the line was smaller; thus, the capture effect appeared to be reduced with flashed nonius lines. Accordingly, we found that the objectively measured vergence gain was significantly correlated (r=0.8) with the motion-amplitude of the flashed monocular line when the separation between the line and the fusion contour was at least 32 min arc. In conclusion, if one wishes to estimate the dynamic vergence response with psychophysical methods, effects of capture of visual direction can be reduced by using flashed nonius lines. 相似文献
15.
Hans C. Fledelius 《Acta ophthalmologica. Supplement》2009,87(7):769-775
Purpose: Chiasmal lesions have been shown to give rise occasionally to uni‐ocular temporal inattention, which cannot be compensated for by volitional eye movement. This article describes the assessments of 46 such patients with chiasmal pathology. It aims to determine the clinical spectrum of this disorder, including interference with reading. Methods: Retrospective consecutive observational clinical case study over a 7‐year period comprising 46 patients with chiasmal field loss of varying degrees. Observation of reading behaviour during monocular visual acuity testing ascertained from consecutive patients who appeared unable to read optotypes on the temporal side of the chart. Visual fields were evaluated by kinetic (Goldmann) and static (Octopus) techniques. Five patients who clearly manifested this condition are presented in more detail. The results of visual field testing were related to absence or presence of uni‐ocular visual inattentive behaviour for distance visual acuity testing and/or reading printed text. Results: Despite normal eye movements, the 46 patients making up the clinical series perceived only optotypes in the nasal part of the chart, in one eye or in both, when tested for each eye in turn. The temporal optotypes were ignored, and this behaviour persisted despite instruction to search for any additional letters temporal to those, which had been seen. This phenomenon of unilateral visual inattention held for both eyes in 18 and was unilateral in the remaining 28 patients. Partial or full reversibility after treatment was recorded in 21 of the 39 for whom reliable follow‐up data were available. Reading a text was affected in 24 individuals, and permanently so in six. Conclusion: A neglect‐like spatial unawareness and a lack of cognitive compensation for varying degrees of temporal visual field loss were present in all the patients observed. Not only is visual field loss a feature of chiasmal pathology, but the higher visual function of affording attention within the temporal visual field by means of using conscious thought to invoke appropriate compensatory eye movement was also absent. This suggests the possibility of ‘trans‐synaptic dysfunction’ caused by loss of visual input to higher visual centres. When inattention to the temporal side is manifest on monocular visual testing it should raise the suspicion of chiasmal pathology. 相似文献
16.
目的:检测视觉发育敏感期单眼形觉剥夺大鼠视觉电生理功能,并观察其视皮质超微结构。方法:健康14日龄SD大鼠20只,随机分为两组,实验组及对照组各10只。实验组大鼠缝合封闭单侧眼,制作单眼形觉剥夺动物模型。与对照组在同等自然光照环境下饲养至45日龄。分别对两组鼠进行电生理检测,并使用透射电镜观察两组大鼠视皮质的超微结构。结果:正常大鼠F-VEP呈现典型的NPN波形,P1波峰潜时短,波峰陡直。形觉剥夺大鼠F-VEP检测结果:P1波峰潜时明显延长,波峰显著降低。电镜观察单眼形觉剥夺动物视皮质神经元的超微结构发现:形觉剥夺动物视皮质中神经元的超微结构受到破坏。结论:单眼形觉剥夺可以影响大鼠视觉电生理的变化,使P波峰的潜时延长,振幅降低,这一改变是形觉剥夺性弱视视觉生理功能改变的体现;单眼形觉剥夺可以引起大鼠视皮质神经元超微结构破坏,这一改变是形觉剥夺性弱视的形态学基础。 相似文献
17.
Changes in visual acuity brought about by altering competitive interactions between the eyes of cats monocularly deprived (MD) from natural eye opening to 7-12 months of age were studied. In MD cats given binocular experience, median visual acuity using the deprived eye was 0.75 c/deg. If the deprived eye was given a slight competitive advantage via reverse-suture, median visual acuity reached 1.52 c/deg. Further, giving the deprived eye the greatest competitive advantage was accomplished by complete removal of the experienced eye which yielded a median deprived eye acuity of 2.3 c/deg. Obstacle avoidance and stimulus size data were also obtained. The previously published electrophysiological effects of these manipulations on striate cortical cells were noted to mirror these increases in visual acuity and this correlation was discussed, as were the effects of analogous manipulations in the monkey and man. 相似文献
18.
Objective To analyze impact factors for visual acuity improvement of senile cataract surgery in Tibet prospectively. Methods Of 278 cases were included. To study relations of visual acuity improvement between pre- and post-cataract surgery with patient age, nucleus classification, small incision cataract surgery (SICS) or Phacoemulsification (PHACO) and corneal edema. LogMAR chart was used in visual acuity analysis. Results 1. Univariate analysis: There was no significant difference between PHACO group and SICS group on visual acuity improvement (PHACO 0.92± 0.48, SICS 0.83± 0.46, P >0.05). Age group for 70- and 80- years-old had less improvement on visual acuity (P <0.05). Diffuse corneal edema had much more influence than central corneal edema on visual acuity improvement (0.52± 0.42, 0.70± 0.44, diffuse vs central, respectively). 2. Multivariate analysis: There were significant differences in age and location of corneal edema on visual acuity improvement (P <0.05). Conclusions There is no significant difference on visual acuity improvement between PHACO and SICS. Ophthalmologist can choose either PHACO or SICS for better rehabilitation of visual acuity, depending on area economics, his own experience and so on in Tibet. Visual acuity improvement in cataract surgery is significantly affected by the age of the patients. Since medication is deficient in Tebit, screening of cataract in Tibet is very important for detecting and treating cataract as early as possible. Diffuse corneal edema has much more influence than central edema on visual acuity improvement when corneal edema degrees are not different. It's important to avoid corneal endothelium damage in cataract surgery. 相似文献
19.
干眼症患者功能视力初探 总被引:2,自引:2,他引:0
目的观察干眼症患者持续睁眼10~20s时其功能视力的变化,以模拟日常生活中因凝视物体瞬目减少情况下的视功能情况,即功能视力。方法观察正常对照组(非干眼症组10人)和干眼症组(非sjogren’s综合征患者10人)日常最好矫正视力和功能视力,并观察他们专注时如阅读和行视野检查时的瞬目频率。结果正常对照组功能视力没有改变(P=0.098),干眼症组由1.15±0.15减少为0.69±0.08,专注时的自然瞬目频率亦减少(P<0.01)。结论干眼症患者持续睁眼10~20s时其功能视力会下降,推测日常从事专注性工作时干眼症患者的视功能会受损,对干眼症患者功能视力的测试更有使用意义。 相似文献
20.
目的 通过测量近视儿童的对比度视力,研究近视儿童对比度下降对视敏度的变化规律,了解其内在差异,探讨相关的影响因索 方法 横断面研究,76名9-16岁的近视儿童全矫后,以多功能视力测试仪MFVA -100测量4种对比度下的(100%、25%、10%、5%)视力.人选的近视儿童的近视范围-1.12~-6.00 D,对比度视力使用logMAR视标设计和记录,分析4种对比度下视力的分布规律,以及不同年龄、屈光度、散光对视敏度表达的影响,采用独立样本t检验和单因索方差分析 结果 ①近视儿童在100%、25%、10%、5%对比度下的平均logMAR视力为- 1.007、0.067、0.303、0.558隧着对比度的下降,其logMAR 值逐渐增大(F=321,P<0.01).对比度视力在在低对比度区间 呈线性下降②根据4个对比度视力指标,将近视儿童分为两个类别,对比度视力较低的儿童占 30.3%.这类儿童同其余儿童在年龄、屈光度和散光上差异无统计学意义③各年龄组、屈光度组及散光组间的对比度视力差异无统计学意义 结论 近视儿童的对比度视力在低对比度区间呈线性下降.对比度视力不受年龄、低中度近视和散光的影响 其存在的内部差异,推测与近视进展的易感性相关. 相似文献