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Sample records for anisometropia

  1. Natural history of infantile anisometropia.

    OpenAIRE

    Abrahamsson, M.; Sjöstrand, J

    1996-01-01

    AIMS/BACKGROUND: In a previous study longitudinal changes of anisometropia were investigated. It was shown that anisometropia arises and vanishes during the emmetropisation process and that the associated risk for amblyopia is low. The aim of this study was to follow acuity and refraction longitudinally in children with marked anisometropia at 1 year of age. METHODS: Refractive errors and visual acuity were estimated every sixth month for a selected group of 20 children with marked anisometro...

  2. Dominant Eye and Visual Evoked Potential of Patients with Myopic Anisometropia

    Science.gov (United States)

    Wang, Qing; Wu, Yili; Liu, Wenwen; Gao, Lin

    2016-01-01

    A prospective nonrandomized controlled study was conducted to explore the association between ocular dominance and degree of myopia in patients with anisometropia and to investigate the character of visual evoked potential (VEP) in high anisometropias. 1771 young myopia cases including 790 anisometropias were recruited. We found no significant relation between ocular dominance and spherical equivalent (SE) refraction in all subjects. On average for subjects with anisometropia 1.0–1.75 D, there was no significant difference in SE power between dominant and nondominant eyes, while, in SE anisometropia ≥1.75 D group, the degree of myopia was significantly higher in nondominant eyes than in dominant eyes. The trend was more significant in SE anisometropia ≥2.5 D group. There was no significant difference in higher-order aberrations between dominant eye and nondominant eye either in the whole study candidates or in any anisometropia groups. In anisometropias >2.0 D, the N75 latency of nondominant eye was longer than that of dominant eye. Our results suggested that, with the increase of anisometropia, nondominant eye had a tendency of higher refraction and N75 wave latency of nondominant eye was longer than that of dominant eye in high anisometropias.

  3. Refração e seus componentes em anisometropia Refraction and its components in anisometropia

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    David Tayah

    2009-02-01

    Full Text Available OBJETIVO: Em anisométropes comparar os valores médios individuais dos componentes oculares de ambos os olhos, correlacionar as diferenças dos componentes com as diferenças de refração; e identificar o menor número de fatores que contenham o mesmo grau de informações expressas no conjunto de variáveis que influenciam a diferença refrativa. MÉTODOS: Realizou-se estudo transversal analítico em população de 77 anisométropes de 2 D ou mais, atendida no ambulatório de Oftalmologia do Hospital Universitário da Faculdade de Medicina Nilton Lins, Manaus. RESULTADOS: Os anisométropes foram submetidos à refração estática objetiva e subjetiva, ceratometria e biometria ultrassônica A-scan. A análise dos dados foi feita por meio dos seguintes modelos estatísticos: análise univariada, multivariada, de regressão múltipla e fatorial. CONCLUSÕES: Não houve diferenças significativas na comparação dos valores médios individuais dos componentes oculares entre os olhos. Houve correlação negativa média entre a diferença refrativa e a diferença de comprimento axial (r= -0,64 (pPURPOSE: To compare the individual means of ocular components of both eyes in patients with anisometropia; to correlate the differences of the components with refractive differences; and to identify the smallest number of factors that contain the same level of information expressed in the set of variables that influence refractive difference. METHODS: An analytical transversal study was carried out in 77 patients with anisometropia of two or more dioptres seen at the Ophthalmologic Clinic, University Hospital, Nilton Lins Medical School, Manaus. RESULTS: All participants were submitted to ophthalmologic examination which included objective and subjective cycloplegic refractometry, keratometry and ultrasound biometry. Data analysis comprised the following statistical models: univariate, multivariate, multiple and factorial regression analyses. CONCLUSIONS

  4. LASIK em pacientes adultos com alta anisometropia: relato de casos LASIK for high anisometropia in adults: case report

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    Patrícia Ioschpe Gus

    2006-04-01

    Full Text Available OBJETIVO: Avaliar a eficácia da técnica laser in situ keratomileusis (LASIK na redução de anisometropia em adultos, para os quais os tratamentos convencionais não tiveram sucesso. MÉTODOS: Série de casos de três olhos de três pacientes adultos, dois do sexo feminino e um do sexo masculino, com idade entre 28 e 49 anos (média de 38,3 anos, os quais foram submetidos à técnica de LASIK. Dois pacientes foram acompanhados por dezoito meses e um por seis meses após a cirurgia. RESULTADOS: Comparando a acuidade visual corrigida do pré-operatório com a acuidade visual não corrigida do pós-operatório, um olho ganhou duas linhas de visão, um olho manteve-se igual e um olho perdeu uma linha de visão. Todos os olhos se mantiveram sem ametropia esférica, e o astigmatismo não excedeu -0,75 D no pós-operatório. CONCLUSÃO: A técnica LASIK mostrou-se eficaz na correção de alta anisometropia em adultos, melhorando a acuidade visual e as queixas astenopéicas, e diminuindo a anisometropia.PURPOSE: To evaluate the efficacy of the laser in situ keratomileusis (LASIK technique in the reduction of anisometropy in adults, for whom conventional treatment was not successful. METHODS: A sequence of cases of three eyes of three adult patients, two females and one male, age ranging from 28 and 49 years (average 38.3 years, who underwent LASIK. Two patients were followed up for eighteen months and one for six months. RESULTS: Comparing the corrected visual acuity before surgery with the non-corrected visual acuity after surgery, one eye gained two lines of vision, one eye remained the same and one eye lost one line of vision. All eyes remained without spheric refraction, and astigmatism did not exceed - 0.75 D after surgery. There has been an improvement in the symptoms of asthenopia in the three patients. CONCLUSION: The LASIK technique proved to be efficient in the correction of anisometropy in adults, improving visual accuity and asthenopia

  5. Correlation of axial length and corneal curvature with diopter in eyes of adults with anisometropia

    OpenAIRE

    Zeng, Jin; Cui, Ying; LI Juan; Xie, Wenjuan; Li, Zhongming; Zhang, Liang; MENG, QIANLI

    2015-01-01

    Purpose: To analyze the causes of anisometropia. Methods: Between June 2011 and November 2012 101 participants were divided into three groups. The refraction comprising the degree of refractive errors in the presence of astigmatism which was converted into the degree of spherical equivalent as well as ocular axial length (AL), corneal curvature (CR), average corneal power (ave K) and diopters were measured. Results: The differences of ocular AL/CR and CR between two eyes were statistically si...

  6. The amblyopic eye in subjects with anisometropia show increased saccadic latency in the delayed saccade task

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    Maciej ePerdziak

    2014-10-01

    Full Text Available The term amblyopia is used to describe reduced visual function in one eye (or both eyes, though not so often which cannot be fully improved by refractive correction and explained by the organic cause observed during regular eye examination. This developmental disorder of spatial vision affects about 2-5% of the population and is associated with abnormal visual experience (e.g. anisometropia, strabismus during infancy or early childhood. Several studies have shown prolongation of saccadic latency time in amblyopic eye. In our opinion, study of saccadic latency in the context of central vision deficits assessment, should be based on central retina stimulation. For this reason, we proposed saccade delayed task. It requires inhibitory processing for maintaining fixation on the central target until it disappears – what constitutes the GO signal for saccade. The experiment consisted of 100 trials for each eye and was performed under two viewing conditions: monocular amblyopic / non-dominant eye and monocular dominant eye. We examined saccadic latency in 16 subjects (mean age 30±11 years with anisometropic amblyopia (two subjects had also microtropia and in 17 control subjects (mean age 28±8 years. Participants were instructed to look at central (fixation target and when it disappears, to make the saccade toward the periphery (10 deg as fast as possible, either left or the right target. The study results have proved the significant difference in saccadic latency between the amblyopic (mean 262±48 ms and dominant (mean 237±45 ms eye, in anisometropic group. In the control group, the saccadic latency for dominant (mean 226±32ms and non-dominant (mean 230±29 ms eye was not significantly different.By the use of LATER (Linear Approach to the Threshold with Ergodic Rate decision model we interpret our findings as a decrease in accumulation of visual information acquired by means of central (affected retina in subjects with anisometropic amblyopia.

  7. Beyond photography: Evaluation of the consumer digital camera to identify strabismus and anisometropia by analyzing the Bruckner's reflex

    Science.gov (United States)

    Bani, Sadat A. O.; Amitava, Abadan K.; Sharma, Richa; Danish, Alam

    2013-01-01

    Amblyopia screening is often either costly or laborious. We evaluated the Canon Powershot TX1 (CPTX1) digital camera as an efficient screener for amblyogenic risk factors (ARF). We included 138 subjects: 84-amblyopes and 54-normal. With the red-eye-reduction feature off, we obtained Bruckner reflex photographs of different sized crescents which suggested anisometropia, while asymmetrical brightness indicated strabismus; symmetry implied normalcy. Eight sets of randomly arranged 138 photographs were made. After training, 8 personnel, marked each as normal or abnormal. Of the 84 amblyopes, 42 were strabismus alone (SA), 36 had anisometropia alone (AA) while six were mixed amblyopes (MA). Overall mean sensitivity for amblyopes was 0.86 (95% CI: 0.83-0.89) and specificity 0.85 (95% CI: 0.77-0.93). Sub-group analyses on SA, AA and MA returned sensitivities of 0.86, 0.89 and 0.69, while specificities were 0.85 for all three. Overall Cohen's Kappa was 0.66 (95% CI: 0.62-0.71). The CPTX1 appears to be a feasible option to screen for ARF, although results need to be validated on appropriate age groups. PMID:24212318

  8. Beyond photography: Evaluation of the consumer digital camera to identify strabismus and anisometropia by analyzing the Bruckner′s reflex

    Directory of Open Access Journals (Sweden)

    Sadat A. O. Bani

    2013-01-01

    Full Text Available Amblyopia screening is often either costly or laborious. We evaluated the Canon Powershot TX1 (CPTX1 digital camera as an efficient screener for amblyogenic risk factors (ARF. We included 138 subjects: 84-amblyopes and 54-normal. With the red-eye-reduction feature off, we obtained Bruckner reflex photographs of different sized crescents which suggested anisometropia, while asymmetrical brightness indicated strabismus; symmetry implied normalcy. Eight sets of randomly arranged 138 photographs were made. After training, 8 personnel, marked each as normal or abnormal. Of the 84 amblyopes, 42 were strabismus alone (SA, 36 had anisometropia alone (AA while six were mixed amblyopes (MA. Overall mean sensitivity for amblyopes was 0.86 (95% CI: 0.83-0.89 and specificity 0.85 (95% CI: 0.77-0.93. Sub-group analyses on SA, AA and MA returned sensitivities of 0.86, 0.89 and 0.69, while specificities were 0.85 for all three. Overall Cohen′s Kappa was 0.66 (95% CI: 0.62-0.71. The CPTX1 appears to be a feasible option to screen for ARF, although results need to be validated on appropriate age groups.

  9. Comparison of the Wave Amplitude of Visually Evoked Potential in Amblyopic Eyes between Patients with Esotropia and Anisometropia and a Normal Group

    Science.gov (United States)

    Talebnejad, Mohammad Reza; Hosseinmenni, Saeedeh; Jafarzadehpur, Ebrahim; Mirzajani, Ali; Osroosh, Enayatollah

    2016-01-01

    Background: We compared the wave amplitude of visually evoked potential (VEP) between patients with esotropic and anisometropic amblyopic eyes and a normal group. Methods: The wave amplitude of VEP was documented in 2 groups of persons with amblyopia (15 with esotropia and 28 with anisometropia) and 1 group of individuals with normal visual acuity (n, 15). The amplitude of P100 was recorded monocularly with different spatial frequencies. Results: Our statistical analysis revealed that the wave amplitude in the 2 groups with amblyopia was significantly decreased compared to that in the normal group (P<0.001). There was a significant difference regarding the amplitude in high spatial frequencies in both high- and low-contrast conditions between the groups with esotropia and anisometropia and the normal group (P<0.001). There were also significant differences in large check-size stimuli and low-contrast condition between the amblyopic groups with esotropia and anisometropia and the normal group (P=0.013 and P=0.044, respectively). In large check-size stimuli and high-contrast condition, a significant difference was indicated only in the comparison between the esotropic amblyopic eyes and the normal eyes (P=0.036). Conclusion: The wave amplitude parameter of VEP was influenced by both types of amblyopia, but it seems that this parameter was more sensitive to esotropic amblyopia than anisometropic amblyopia. This outcome may reflect a non-parallel pattern of cortical responses in the comparison of the 2 types of amblyopia with each other and with the control group, which may be beneficial for the diagnosis and treatment of amblyopia. PMID:26989279

  10. Clinal effects of LASIK on binocular vision in myopic anisometropia%近视性屈光参差患者LASIK术后双眼视功能评估

    Institute of Scientific and Technical Information of China (English)

    杨亮; 胡琦; 康杨; 黄磊; 王珂萌

    2012-01-01

    目的 观察近视性屈光参差患者接受准分子激光原位角膜磨镶术( LASIK)后双眼视功能的变化,探讨LASIK手术矫治近视性屈光参差对三级视功能的影响,从双眼视觉的变化评价其临床应用价值.设计前瞻性病例系列.研究对象36例(72眼)行LASIK手术的近视性屈光参差患者(双眼屈光参差≥2.50 D).方法 对36例行LASIK手术的近视性屈光参差患者分别于手术前和手术后3个月进行裸眼视力、最佳矫正视力、屈光状态和同视机双眼视功能的检测,并对双眼视功能的变化进行随访研究.主要指标手术前后裸眼视力、最佳矫正视力、屈光度、同时视、融合功能、远立体视和近立体视.结果 术前72眼的裸跟视力在0.01-0.2之间,术后3个月时均达到1.0.双跟屈光参差由术前的(5.01±1.96)D( 2.50~9.00 D),降低到术后3个月的( 0.28±0.22 )D(0.00~0.75 D).手术前后的屈光参差度的改变,差异均有显著统计学意义(P<0.01).26例屈光参差量≥2.50 D且≤6.00 D的高度屈光参差者术前戴框架眼镜下近立体视正常的12例,术后3个月增至22例,差异有统计学意义(P<0.05);16例屈光参差量>6.0D的重度屈光参差者手术前后均没有正常近立体视.术前戴框架眼镜下三级视功能(同时视、融合功能、远立体视)正常的分别为33例、18例、13例,LASIK术后3个月三级视功能正常的分别为34例、33例、23例,手术后获得融合功能和远立体视者较术前明显增加(P均<0.05).结论 LASIK矫治近视性屈光参差,不仅可提高患者裸眼视力,而且可通过减小患者双眼间的屈光差异,增加双眼物像的融合,改善立体视功能.%Objective To analyze the clinical effects on binocular vision after LASIK for myopic anisomelropia, and evaluate its clinical value in the view of vision quality. Design Prospective case series. Participants 36 cases (72 eyes) with myopic anisometropia who received

  11. 近视性高度屈光参差眼屈光参数和角膜生物学参数的研究%Research of refractive index and corneal biological parameter in high myopic anisometropia eyes

    Institute of Scientific and Technical Information of China (English)

    许爱琴; 方海珍

    2011-01-01

    Objective To investigate the differences of refractive index and corneal biological parameter in high myopic anisometropia.Methods Twenty three subjects who suffered anisometropia (spherical equivalent ≥6.00 D) were selected.For each subject,corneal hysteresis (CH) was measured by ORA (Ocular Response Analyzer),central corneal thickness (CCT) was measured by OCT,average keratometer value (mean K) and ocular axial length (AL) were measured by Zeiss IOL-Master,the results were tested by paired t-test and multiple linear regression.Result The differences of mean K,CCT for two eyes were not significant (P >0.05).Mean AL was (28.34± 1.10) mm (SD) in high myopic eyes compared with (24.53± 0.70) mm in the fellow eye,the difference was statistically significant (P <0.0001).The mean hysteresis in high myopic eyes and the fellow eyes was (10.00± 1.61)mmHg and (10.96± 1.38) mmHg,respectively; the difference was statistically significant (P <0.0001).The relationship between CH and AL and CCT was statistically significant (P <0.05).Conclusions Under the same gene and environment,the corneal hysteresis value is significantly lower in high myopia,which has no thinner cornea.It may be due to the change in cornea microstructure as a result of axial abnormal elongation.%目的 分析和研究近视性的高度屈光参差眼屈光参数及角膜生物学参数的差异性.方法 对23名近视性的高度屈光参差患者(双眼等效球镜SE差≥6.00D),用眼反应分析仪(Ocular Response Analyzer,ORA)测量角膜滞后性(Corneal Hyteresis,CH),用改进的光学相干断层扫描仪(OCT-3)测量中央角膜厚度(CCT),用IOL-Master测量角膜曲率(mean K)及眼轴长度(AL).统计处理采用配对t检验和多元线性回归分析.结果 近视程度高度眼平均AL(28.34±1.10)mm,低度眼平均AL( 24.53±0.70)mm,差异有统计学意义(P<0.01).双眼角膜平均曲率K差异无统计学意义(P>0.05).双眼CCT差异无统计学意义(P>0.05).

  12. LASIK矫治远视屈光参差性弱视儿童及青少年的临床疗效研究%Long-term clinical curative effect of the LASIK surgery on hyperopic anisometropia amblyopic children and adolescent

    Institute of Scientific and Technical Information of China (English)

    马月磊; 郭秀瑾; 刘超敏; 李向品

    2016-01-01

    Objective To investigate the long-term clinical curative effect and the improvement of the binocular visual function after hyperopic anisometropia amblyopic children and adolescent LASIK surgery.Methods Retrospective study of 75 cases with the anisometropia amblyopia received excimer laser treatment of hyperopic LASIK surgery in the center of second hospital,Hebei medical university from May 2008 to June 2013.They were divided to the group of children and adolescents according to the age,the condition of the aye after surgery,observation index,follow-up observation analysis,and compared with preoperative.Results The postoperative visual acuity of naked eye,the postoperative best corrected visual acuity,postoperative equivalent ball lens,postoperative binocular anisometropia of 75 cases were observed and compared with the preoperative,and the difference had statistical significance (P <0.05).All postoperative complications were not seen at all stages such as corneal opacity,and no open hole at the time of the last follow-up eyesight drops,best corrected vision,stereo vision preoperative obviously improved.There was no significant difference between the posterior surface height and the preoperative.Conclusions The farsightedness anisometropia amblyopic children and adolescents LASIK refractive surgery has good safety,efficacy,predictability and stability,and can effectively improve the patient's stereo vision.%目的 探讨准分子激光原位角膜磨镶术(LASIK)矫治远视屈光参差性弱视儿童及青少年的临床疗效及双眼视功能的改善情况.方法 回顾性系列病例临床研究.对2008年5月至2013年6月在河北医科大学第二医院准分子激光治疗中心,接受LASIK手术的远视屈光参差性弱视儿童及青少年75例,按年龄分为儿童组和青少年组,分别对其术后眼部情况、观察指标、随访情况进行观察,并与术前进行对比.结果 两组中所有患者术后视力、等效球镜、双眼屈

  13. Identical twins with “mirror image” anisometropia and esotropia

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    Stanković-Babić Gordana; Vujanović Milena; Cekić Sonja

    2011-01-01

    Introduction. Identical twins account for 0.2% of the world population and 8% of all twins. A “mirror image” variation can be found in 25% of identical twins. Studies of twins assume a special place in human genetics due to the possibility of comparing genetic and other factors. We present two pairs of identical male twins with mirror-image astigmatism and esotropia. Case Outline. The first was a pair of twelve-year old identical twins with “mirror image” myopic astigmatism. The Twin 1 ...

  14. Identical twins with “mirror image” anisometropia and esotropia

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    Stanković-Babić Gordana

    2011-01-01

    Full Text Available Introduction. Identical twins account for 0.2% of the world population and 8% of all twins. A “mirror image” variation can be found in 25% of identical twins. Studies of twins assume a special place in human genetics due to the possibility of comparing genetic and other factors. We present two pairs of identical male twins with mirror-image astigmatism and esotropia. Case Outline. The first was a pair of twelve-year old identical twins with “mirror image” myopic astigmatism. The Twin 1 had myopic astigmatism in the right eye, while the Twin 2 was affected by the left eye myopic astigmatism. The second was a pair of six-year old identical twins with esotropia and hypermetropic astigmatism. The Twin 1 had esotropia in the left eye, while the right eye was affected in the Twin 2. Esotropia was surgically corrected. Conclusion. In this study we pointed to the role of genetic factors in the development of refractive error, as well as the type of strabismus. Refraction anomalies (myopia, hypermetropia and astigmatism are complex heterogeneous disorders and ideal for genetic investigation. The knowledge of genetic mechanisms involved in refractive error susceptibility may allow treatment to prevent progression or to further examine gene-environment interactions. We hope that this paper will initiate further investigation of refraction anomalies in twins and future multicentre studies, which, to our knowledge, have not been conducted in our country so far.

  15. The effect of LASIK in anisometropia on strabismus%LASIK手术治疗屈光参差对斜视的影响

    Institute of Scientific and Technical Information of China (English)

    吴西西

    2003-01-01

    目的:探索LASIK手术治疗屈光参差后对斜视的影响.方法:用美国VISX准分子激光为25例屈光参差患者行手术治疗.结果:术后有2例外斜患者较术前斜视度数减少5△,1例患者术后增加7..结论:LASIK治疗屈光参差后对斜视无显著影响.

  16. Management of Strabismus in Myopes.

    Science.gov (United States)

    Kekunnaya, Ramesh; Chandrasekharan, Anjali; Sachdeva, Virender

    2015-01-01

    Strabismus in myopes can be related to anisometropia, accommodation/convergence effects, and/or muscle path deviations. This review article highlights management considerations in myopic patients. PMID:26180467

  17. Management of strabismus in myopes

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    Ramesh Kekunnaya

    2015-01-01

    Full Text Available Strabismus in myopes can be related to anisometropia, accommodation/convergence effects, and/or muscle path deviations. This review article highlights management considerations in myopic patients.

  18. Clinical Course and Response to Therapy in Different Types of Amblyopia

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    Reşat Duman

    2013-10-01

    Full Text Available Purpose: We aimed to compare the demographic features, visual acuities before and after treatment, amblyopia and strabismus degrees and binocular visual functions in cases with anisometropic, strabismic and/or anisometropic amblyopia. Material and Method: The study included 50 anisometropic, 50 strabismic and 50 anisometropic and strabismic cases that were followed up with the diagnosis of amblyopia, in our clinic, between January 2007 - September 2010. Amblyopia criteria was defined as the best corrected visual acuity of ≤0.8 and at least 2 lines difference between the visual acuities of two eyes. Anisometropia was defined as ≥1D difference in the spherical and cylindrical value between two eyes. Results: The groups were statistically similar in means of age and sex distribution. Visual acuities in amblyopic eyes before and after treatment were also statistically similar. There were no significant difference between 3 groups in means of compliance to occlusion therapy. In anisometropic cases, anisometropic spherical values were found to have position correlation with amblyopia degree. In hypermetropic and myopic cases, a strong correlation was shown between anisometropia and amblyopia, especially in hypermetropic cases, amblyopia degree increased as the anisometropia increased. In all strabismus cases, a positive correlation between strabismus and amblyopia degrees was shown even though it was statistically insignificant. In strabismic cases, esotropia was significantly higher than exotropia. In anisometropia group, stereopsis and fusion was found to be preserved better in comparison to the strabismic cases. It was concluded that deviation had a more profound effect on binocular function loss than anisometropia. Discussion: We recommend to follow the hypermetropic anisometropic cases and especially cases with high degree strabismus and esotropia more closely. And also we emphasize that strabismus affects binocular function loss more than

  19. Refraction and visual acuity in a national Danish cohort of 4-year-old children of extremely preterm delivery

    DEFF Research Database (Denmark)

    Fledelius, Hans C; Bangsgaard, Regitze; Slidsborg, Carina; laCour, Morten

    2015-01-01

    refractive distribution presented a myopic tail (4.5%) and a hyperopic tail (11.9% ≥+2.5 D) as special preterm features, and corneas were more curved. Astigmatism and anisometropia were only marginally increased, and visual acuities were generally good. Best-corrected binocular median logMAR visual acuity...

  20. Phakic anterior chamber intraocular lens (Verisyse™) implantation in children for treatment of severe ansiometropia myopia and amblyopia: Six-month pilot clincial trial and review of literature

    OpenAIRE

    Pirouzian, Amir; Ip, Kenneth C; O’Halloran, Henry S

    2009-01-01

    Purpose: The current study aims to evaluate both safety and efficacy of Verisyse™ (AMO, Irvine, CA) phakic anterior chamber intraocular lens (IOL) in the reduction of clinically significant (>−8 D) myopic anisometropia in children who are noncompliant to traditional medical treatment including spectacle correction or contact lenses. Design: Retrospective interventional case series. Methods: Six anisometropic myopic pediatric patients in one practice were identified through chart-review. None ...

  1. Phakic anterior chamber intraocular lens (Verisyse™) implantation in children for treatment of severe ansiometropia myopia and amblyopia: Six-month pilot clincial trial and review of literature

    OpenAIRE

    Pirouzian, Amir

    2009-01-01

    Amir Pirouzian1,3, Kenneth C Ip2, Henry S O’Halloran31The Permanente Medical Group, Santa Clara, CA, USA; 2The Permanente Medical Group, San Francisco, CA, USA; 3Rady’s Children’s Hospital of San Diego, San Diego, CA, USAPurpose: The current study aims to evaluate both safety and efficacy of Verisyse™ (AMO, Irvine, CA) phakic anterior chamber intraocular lens (IOL) in the reduction of clinically significant (>-8 D) myopic anisometropia in childre...

  2. The Importance of the Relationship Between The Position of the Correcting Lens Principal Planes (H'1-H'2) and Principal Planes (H1-H2) of the Optical Eye System – Aphakic Correction

    OpenAIRE

    Vojniković, Božo; Njirić, Sanja

    2013-01-01

    In the clinical refraction of the eye, aniseikonia and anisometropia are inevitably used terms. Image formation and its retinal size is the function of the power of the dioptric eye system. However, the correcting lens in front of the eye and the eye optical system represent a unique optical afocal system, in which the distance between correcting lens and corneal vertex is of utmost importance, since it determines the size (together with appropriate correcting lens) of the retinal image. In t...

  3. Amblyopia in children : Therapy and follow-up

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    Agervi, Pia

    2009-01-01

    Amblyopia, the leading cause of unilateral visual impairment in children, is caused by inadequate stimulation of the visual system during the sensitive periods of visual development in childhood. Cataract, anisometropia and strabismus are well-known causes of amblyopia. Bilateral congenital cataract is a common cause of treatable childhood blindness. Early surgery and intense postoperative amblyopia therapy can result in good visual acuity (VA). In the developing world, the...

  4. Asthenopia in schoolchildren

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    Abdi, Saber

    2007-01-01

    Asthenopia is a term used to describe different symptoms associated with the use of the eyes, such as pain, blurred vision, diplopia, headaches. Asthenopia is most often reported in association with near vision. Children with asthenopia complain of such symptoms particularly when reading and writing. Asthenopia is often divided into two main categories: refractive including refractive errors and anisometropia, and muscular, comprising strabismus and convergence insufficiency...

  5. Long-term analysis of LASIK for the correction of refractive errors after penetrating keratoplasty.

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    Hardten, David R.; Chittcharus, Anuwat; Lindstrom, Richard L

    2002-01-01

    PURPOSE: To determine the long-term safety and effectiveness of laser-assisted in situ keratomileusis (LASIK) in the treatment of refractive errors following penetrating keratoplasty. METHODS: A retrospective review was done of 57 eyes of 48 patients with anisometropia or high astigmatism who were unable to wear glasses or a contact lens after penetrating keratoplasty and who underwent LASIK for visual rehabilitation. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (B...

  6. Treatment of amblyopia in the adult: insights from a new rodent model of visual perceptual learning.

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    Joyce eBonaccorsi; Nicoletta eBerardi; Alessandro eSale

    2014-01-01

    Abstract Amblyopia is the most common form of impairment of visual function affecting one eye, with a prevalence of about 1-5% of the total world population. Amblyopia usually derives from conditions of early functional imbalance between the two eyes, owing to anisometropia, strabismus, or congenital cataract, and results in a pronounced reduction of visual acuity and severe deficits in contrast sensitivity and stereopsis. It is widely accepted that, due to a lack of sufficient plasticity...

  7. Suturing technique for control of postkeratoplasty astigmatism and myopia.

    OpenAIRE

    Dursun, Dilek; Forster, Richard K.; Feuer, William J.

    2002-01-01

    PURPOSE: We previously demonstrated that selective suture removal reduces keratoplasty astigmatism; however, a myopic shift was induced with increasing number of interrupted sutures removed. This study is an attempt to determine the effects of a modified surgical technique on postkeratoplasty myopia, astigmatism, and anisometropia. METHODS: Optical penetrating keratoplasties were performed on 92 eyes of 84 patients. The study group consisted of 92 consecutive penetrating keratoplasties perfor...

  8. The Influence of Retinalamine on the Myopic Process in Schoolchildren

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    N. N. Aleksandrova; L. E. Fedorischeva; K.Yu. Yeremenko

    2009-01-01

    The paper presents results of complex treatment of 422 children with myopia of various degrees aged from 7 to 17 years. The main group included 265 children: 124 patients with myopia, 141 — with myopia and Computer Visual Syndrome (CVS) and 78 children with anisometropia. The control group consisted of 157 patients. 1% Emoxipine and 4% Taufone were used in children of the control group. Modern methods of examination showed more effective influence of Retinalamine on the visual functions. The ...

  9. Association of extensive myelinated nerve fibers and high degree myopia: Case report

    OpenAIRE

    Elvan Yalcın; Ozlem Balcı; Ziya Akıngol

    2013-01-01

    Unilateral extensive myelination of the peripapillary nerve fibers may be associated with anisometropic myopia, strabismus, and reduced vision. Myelination of optic nerve fibers terminate at lamina cribrosa. Yet in some patients, myelination progresses into the peripapillary retinal nerve fibers and may affect the visual acuity. In this report, we described 4 patients. All patients presented extensive peripapillary myelinated nerve fibers associated with myopic anisometropia. After routine op...

  10. Refractive Status of Chinese with Laser-Treated Retinopathy of Prematurity

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    Ruan, Lu; Shan, Hai-Dong; Liu, Xing-Zong; Huang, Xin

    2015-01-01

    ABSTRACT Purpose To analyze changes in myopia, astigmatism, and anisometropia after laser treatment of retinopathy of prematurity (ROP), including aggressive posterior retinopathy of prematurity (APROP), in Mainland Chinese children. Methods This was a retrospective study of children who had laser treatment for threshold or type 1 prethreshold ROP between January 2004 and October 2012 and age-matched control subjects with spontaneously regressed type 2 prethreshold ROP. One hundred fifteen ey...

  11. Prevalence of amblyopia and refractive errors among primary school children

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    Zhale Rajavi

    2015-01-01

    Results: Amblyopia was present in 2.3% (95% CI: 1.8% to 2.9% of participants with no difference between the genders. Amblyopic subjects were significantly younger than non-amblyopic children (P=0.004. Overall, 15.9% of hyperopic and 5.9% of myopic cases had amblyopia. The prevalence of hyperopia ≥+2.00D, myopia ≤-0.50D, astigmatism ≥0.75D, and anisometropia (≥1.00D was 3.5%, 4.9%, 22.6%, and 3.9%, respectively. With increasing age, the prevalence of myopia increased (P<0.001, that of hyperopia decreased (P=0.007, but astigmatism showed no change. Strabismus was found in 2.3% of cases. Strabismus (OR=17.9 and refractive errors, especially anisometropia (OR=12.87 and hyperopia (OR=11.87, were important amblyogenic risk factors. Conclusion: The high prevalence of amblyopia in our subjects in comparison to developed countries reveals the necessity of timely and sensitive screening methods. Due to the high prevalence of amblyopia among children with refractive errors, particularly high hyperopia and anisometropia, provision of glasses should be specifically attended by parents and supported by the Ministry of Health and insurance organizations.

  12. Crianças usuárias de lente de contato nos serviços público e privado: análise comparativa Pediatric contact lens users in public and private services: comparative analysis

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    Daniela Araújo Toscano

    2009-04-01

    Full Text Available OBJETIVOS: Analisar as indicações, tipo, complicações do uso de lentes de contato e acuidade visual em crianças de serviços de Oftalmologia público e privado. MÉTODOS: Os dados dos prontuários de 59 crianças usuárias de lentes de contato em serviço privado (Hospital de Olhos de Pernambuco - Grupo 1, e 43 no serviço público (Fundação Altino Ventura - Grupo 2, foram analisados. A coleta de dados incluiu características sociodemográficas, idade da primeira consulta, indicação do uso da lente, tipo de lente, complicações e acuidade visual. RESULTADOS: As mais comuns indicações do uso de lente de contato no grupo 1 foram: ametropia (55,9%, anisometropia (18,6% e esotropia (16,9%. Neste grupo o leucoma e phthisis não estavam presentes. No grupo 2, as indicações mais comuns foram: anisometropia (23,2%, ametropia e leucoma (18,6% cada, e phthisis (16,3%. A esotropia não apareceu no grupo 2. O tipo de lente de contato mais prescrita foi a gelatinosa de uso permanente (não descartável no grupo 1 (45,8% e no grupo 2 (32,6%. A complicação mais encontrada no grupo 1 foi desconforto (33,3% e no grupo 2 perda da lente (60%. CONCLUSÕES: A indicação de ametropia predominou nos pacientes privados e as anisometropias nos públicos. O tipo de lente de contato mais prescrita nos dois grupos foi a gelatinosa de uso permanente. A complicação mais frequente no grupo 1 foi desconforto e no grupo 2 perda da lente. A acuidade visual na maioria dos pacientes manteve-se.PURPOSE: To analyze the indications, type and complications of contact lens use and visual acuity in children, in ophthalmological, public and private, services. METHODS: The information from the medical records of 59 contact lens users at a private service (Hospital de Olhos de Pernambuco - Recife - PE- Brazil - group 1, and 43 at public service (Fundação Altino Ventura - Recife - PE - Brazil - group 2, was analyzed. The collected data included: demographic information

  13. Três anos pós-LASIK em crianças anisométropes de 8 a 15 anos de idade Three years after LASIK in anisometropic children from 8 to 15 years old

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    Belquiz R. Amaral Nassaralla

    2003-01-01

    Full Text Available OBJETIVO: Determinar a segurança, eficácia, previsibilidade e estabilidade da técnica "laser in situ keratomileusis" (LASIK, três anos após a cirurgia, para a correção de alta anisometropia em crianças, para as quais os tratamentos convencionais não obtiveram êxito. MÉTODOS: Nove olhos de nove pacientes, três meninos e 6 meninas, com idade média de 11,5 anos (variando de 8 a 15 anos, foram submetidos à técnica LASIK utilizando-se o excimer laser Chiron Technolas 217. O tempo mínimo de seguimento foi de 36 meses. RESULTADOS: Três anos após o LASIK, a acuidade visual sem correção (AVSC melhorou pelo menos 5 linhas em todos os olhos; cinco olhos (55,5% apresentavam AVSC de 20/50 ou melhor. Seis olhos (66,6%, apresentavam acuidade visual com correção (AVCC de 20/50 ou melhor e cinco olhos (55,5% ganharam pelo menos 1 linha na AVCC. Devido a ambliopia, nenhum olho apresentou AVSC de 20/20 ou melhor. A média do equivalente esférico pré-operatório foi reduzida de -7,66 (± 3,75 D para -1,02 (± 1,26 D e a do astigmatismo, de -3,11 (± 2,09 D para -0,75 (± 0,25 D. A maior anisometropia encontrada foi de 1,5 D. CONCLUSÕES: Após três anos de seguimento, a técnica LASIK parece ser opção segura e eficaz na correção de alta anisometropia em crianças entre 8 e 15 anos de idade, para os quais os tratamentos convencionais não obtiveram êxito. A progressão do erro refracional relacionada à idade não impediu o uso da correção visual adequada.PURPOSE: To determine the safety, efficacy, predictability and stability of laser in situ keratomileusis (LASIK, three years after surgery, to correct high myopia or high myopic astigmatism in children with high anisometropia in whom conventional treatments had failed. METHODS: Nine eyes of 9 patients, 3 boys and 6 girls with a mean age of 11.5 years (range, 8 to 15 years underwent LASIK using the Chiron Technolas 217 excimer laser. Minimum follow-up was 36 months. RESULTS: Three

  14. Prevalence of Refractive Errors; the Yazd Eye Study

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    Hossein Ziaei

    2013-01-01

    Full Text Available Purpose: To determine the prevalence of refractive errors in Yazd, central Iran. Methods: This population-based study was performed in 2010-2011 and targeted adults aged 40 to 80 years. Multi-stage random cluster sampling was applied to select samples from urban and rural residents of Yazd. Manifest refraction, visual acuity measurement, retinoscopy and funduscopy were performed for all subjects. Myopia, hyperopia, astigmatism and anisometropia were defined as spherical equivalent (SE +0.50 D, cylindrical error >0.5 D and SE difference ≥1 D between fellow eyes, respectively. Results: From a total of 2,320 selected individuals, 2,098 subjects (90.4% participated out of which 198 subjects were excluded due to previous eye surgery. The prevalence (95% confidence interval for myopia, hyperopia, astigmatism, anisometropia, -6 D myopia or worse, and 4 D hyperopia or worse was 36.5% (33.6-39.4%, 20.6% (17.9- 23.3%, 53.8% (51.3-56.3%, 11.9% (10.4-13.4%, 2.3% (1.6-2.9% and 1.2% (0.6-1.8%, respectively. The prevalence of hyperopia, astigmatism and anisometropia increased with age. The prevalence of myopia was significantly higher in female subjects. The prevalence of with-the-rule, against-the-rule and oblique astigmatism was 35.7%, 13.4% and 4.6%, respectively. The prevalence of against-the-rule astigmatism increased with age (P<0.001; with-the-rule astigmatism was more common in women (P=0.038. Conclusion: More than half of the study population had refractive errors; the prevalence of myopia and astigmatism was higher than earlier studies in Iran. Since refractive errors are a major cause of avoidable visual impairment, their high prevalence in this survey is important from a public health perspective.

  15. Reabilitação visual com lentes de contato após trauma ocular Visual rehabilitation with contact lenses after ocular trauma

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    Adamo Lui Netto; Aline Cristina Fioravanti Lui; Giovana Arlene Fioravanti Lui

    2008-01-01

    Trauma ocular é causa importante de baixa de acuidade visual em todos os países do mundo. A integridade do bulbo ocular é primordial para recuperação visual nesses pacientes. Acidentes domésticos, automobilísticos, esportivos, além de queimaduras químicas e térmicas são as principais causas de trauma em nosso meio. O uso de lentes de contato é indicado para a reabilitação visual em casos de astigmatismos regulares ou irregulares de córnea, anisometropias, afacias, opacidades paracentrais supe...

  16. Clinical studies of fully automatic computer optometry to test children astigmatism and the change of axial

    OpenAIRE

    Xiao-Zhen Huang

    2015-01-01

    AIM: To observe and analyze the detection results of child astigmatism before and after cycloplegia and axial changes by using computer automatic refractometer. METHODS:Sixty cases(120 eyes)with anisometropia founded by subjective optometry were selected as the research object. According to age, they were divided into 3~6 years groups(14 cases, 28 eyes), 7~9 years group(29 cases, 58 eyes)and 10~12 years group(17 cases, 34 eyes). Three groups of patients were given compound tropicamide eye dro...

  17. Recovery of Accommodative Capabilities of Ocular Pseudophakia

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    Ivonin K.S.

    2012-12-01

    Full Text Available There are considered three modern prospective ways to solve the problem of pseudophakic presbyopia: development of induced anisometropia (monovision, and implantation of accommodative and pseudo-accommodative intraocular lens (IOL. According to the findings of numerous studies, pseudophakic monovision enables to achieve good results of close-up and distant acuity of vision without correction. However, monovision use involves such limitations as individual intolerance to anisometropia, and the lack of stereoscopic vision. Despite accommodative IOL have more potential, accommodative effect after the implantation of this type of lens is not always guaranteed. There can be several reasons for that, including inconsistency between IOL diameter and capsular sac diameter, incorrect capsulorrhexis diameter, increased or reduced ciliary muscle contraction, capsular sac fibrosis, synchysis corporis vitrei, posterior vitreous detachment, the change of lens ligament elasticity. Currently, the use of pseudo-accommodative IOL is the most effective way of pseudophakic presbyopia correction, and among them the most effective ones are bifocal refractive and diffractive IOL. But along with the recognized advantages of the lens, they have a number of disadvantages, e.g. low intermediate vision.

  18. Immediate Sequential Bilateral Cataract Surgery: A Systematic Review and Meta-Analysis

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    Line Kessel

    2015-01-01

    Full Text Available The aim of the present systematic review was to examine the benefits and harms associated with immediate sequential bilateral cataract surgery (ISBCS with specific emphasis on the rate of complications, postoperative anisometropia, and subjective visual function in order to formulate evidence-based national Danish guidelines for cataract surgery. A systematic literature review in PubMed, Embase, and Cochrane central databases identified three randomized controlled trials that compared outcome in patients randomized to ISBCS or bilateral cataract surgery on two different dates. Meta-analyses were performed using the Cochrane Review Manager software. The quality of the evidence was assessed using the GRADE method (Grading of Recommendation, Assessment, Development, and Evaluation. We did not find any difference in the risk of complications or visual outcome in patients randomized to ISBCS or surgery on two different dates. The quality of evidence was rated as low to very low. None of the studies reported the prevalence of postoperative anisometropia. In conclusion, we cannot provide evidence-based recommendations on the use of ISBCS due to the lack of high quality evidence. Therefore, the decision to perform ISBCS should be taken after careful discussion between the surgeon and the patient.

  19. Long-term efficacy of excimer laser in situ keratomileusis in the management of children with high anisometropic amblyopia

    Institute of Scientific and Technical Information of China (English)

    LIN Xiao-ming; YAN Xiao-he; WANG Zheng; YANG Bin; CHEN Qi-wen; SU Jin-ai; YE Xue-lian

    2009-01-01

    Background Children with anisometropic amblyopia are often noncompliant with traditional treatment including spectacules and contact lenses.This study was to evaluate the long-term efficacy of excimer laser in situ keratomileusis (LASIK) for children with high anisometropic amblyopia.Methods A retrospective analysis of 24 children with high unilateral anisometropic amblyopia,who underwent LASIK during the period between August 2000 and September 2005 in our hospital,was conducted.The mean age of these children was (7.4±1.9) years (range 5-14 years) and the mean follow-up period was (33.3±14.2) months (range 18.5-74.2 months).After LASIK,visual acuity,refraction and far or near stereoacuity were analyzed.Near stereoacuity was measured by the random-dot butterfly stereogram and the pre-school random-dot stereogram,while far stereoacuity was measured by the synoptophore with Yan's random-dot stereogram.Results Mean preoperative uncorrected visual acuity was 0.06±0.05,while mean postoperative uncorrected visual acuity was elevated to 0.43±0.33.Mean preoperative best-corrected visual acuity was 0.26±0.22,while mean postoperative best-corrected visual acuity was elevated to 0.67±0.40.For patients with myopic anisometropia,preoperative mean spherical equivalent refraction was (-8.01±2.70) D while postoperative value significantly reduced to (-1.32±2.47) D.For patients with hyperopic anisometropia,preoperative mean spherical equivalent refraction was (+7.35±1.55) D while postoperative value significantly reduced to (+3.30±0.86) D.These results demonstrated that there was statistical difference in these parameters between preoperative and postoperative tests.At the last follow-up,20 patients had near stereoacuity,and the mean near stereoacuities measured by the random-dot butterfly stereogram and the preschool random-dot stereogram were (149.00±152.93)" and (201.05±235.94)",respectively.In contrast,11 patients had far stereoacuity,and the mean far stereoacuity

  20. Exposure to sunlight reduces the risk of myopia in rhesus monkeys.

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    Yong Wang

    Full Text Available Exposure to sunlight has recently been postulated as responsible for the effect that more time spent outdoors protects children from myopia, while early life exposure to natural light was reported to be possibly related to onset of myopia during childhood. In this study, we had two aims: to determine whether increasing natural light exposure has a protective effect on hyperopic defocus-induced myopia, and to observe whether early postnatal exposure to natural light causes increased risk of refractive error in adolescence. Eight rhesus monkeys (aged 20-30 days were treated monocularly with hyperopic-defocus (-3.0D lens and divided randomly into two groups: AL group (n=4, reared under Artificial (indoor Lighting (08:00-20:00; and NL group (n=4, exposed to Natural (outdoor Light for 3 hours per day (11:00-14:00, and to indoor lighting for the rest of the light phase. After being reared with lenses for ca. 190 days, all monkeys were returned to unrestricted vision until the age of 3 years. Another eight age-matched monkeys, reared with unrestricted vision under artificial lighting since birth, were employed as controls. The ocular refraction, corneal curvature and axial dimensions were measured before lens-wearing (at 23±3 days of age, monthly during the light phase, and at the age of puberty (at 1185+3 days of age. During the lens-wearing treatment, infant monkeys in the NL group were more hyperopic than those in the AL group (F=5.726, P=0.032. Furthermore, the two eyes of most NL monkeys remained isometropic, whereas 3 of 4 AL monkeys developed myopic anisometropia more than -2.0D. At adolescence, eyes of AL monkeys showed significant myopic anisometropia compared with eyes of NL monkeys (AL vs NL: -1.66±0.87D vs -0.22±0.44D; P=0.002 and controls (AL vs Control: -1.66±0.87D vs -0.05±0.85D; P<0.0001. All differences in refraction were associated with parallel changes in axial dimensions. Our results suggest that exposure to natural outdoor

  1. Current management of presbyopia

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    Pandelis A Papadopoulos

    2014-01-01

    Full Text Available Presbyopia is a physiologic inevitability that causes gradual loss of accommodation during the fifth decade of life. The correction of presbyopia and the restoration of accommodation are considered the final frontier of refractive surgery. Different approaches on the cornea, the crystalline lens and the sclera are being pursued to achieve surgical correction of this disability. There are however, a number of limitations and considerations that have prevented widespread acceptance of surgical correction for presbyopia. The quality of vision, optical and visual distortions, regression of effect, complications such as corneal ectasia and haze, anisometropia after monovision correction, impaired distance vision and the invasive nature of the currently techniques have limited the utilization of presbyopia surgery. The purpose of this paper is to provide an update of current procedures available for presbyopia correction and their limitations.

  2. Pseudophakic monovision is an important surgical approach to being spectacle-free

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    JianHe Xiao

    2011-01-01

    Full Text Available There are few studies on pseudophakic monovision even though it is widely applied. We reviewed the published literature on pseudophakic monovision. Surgeons select patients who not only have a strong desire to be free of glasses after surgery, but also fully understand monovision design and its drawbacks. However, other criteria adopted for pseudophakic monovision are very different. Both traditional monovision and cross monovision are used in pseudophakic monovision, and the target binocular anisometropia ranges from -1.0 D to -2.75 D. Postoperative results were acceptable in every study and most patients were satisfied, with vision being improved and presbyopia corrected. Complications were decreased stereopsis, contrast sensitivity, and visual fields, similar to other types of monovision. The term "pseudophakic monovision" should include more than just monocular intraocular lens implantation in two eyes, and further studies are required.

  3. Association of extensive myelinated nerve fibers and high degree myopia: Case report

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    Elvan Yalcın

    2013-01-01

    Full Text Available Unilateral extensive myelination of the peripapillary nerve fibers may be associated with anisometropic myopia, strabismus, and reduced vision. Myelination of optic nerve fibers terminate at lamina cribrosa. Yet in some patients, myelination progresses into the peripapillary retinal nerve fibers and may affect the visual acuity. In this report, we described 4 patients. All patients presented extensive peripapillary myelinated nerve fibers associated with myopic anisometropia. After routine ophthalmic and orthoptic examinations, all patients underwent treatment for amblyopia through correction with spectacles, contact lenses, and the occlusion of the good eye. Corrected visual acuity improved in 1 patient, but 3 patients had no increase in visual acuity despite treatment with full cycloplegic refraction and appropriate patching. Probably because of structural abnormalies of the macula, visual results are often disappointing with appropriate correction of the refractive error and occlusion.

  4. A double dissociation of the acuity and crowding limits to letter identification, and the promise of improved visual screening.

    Science.gov (United States)

    Song, Shuang; Levi, Dennis M; Pelli, Denis G

    2014-01-01

    Here, we systematically explore the size and spacing requirements for identifying a letter among other letters. We measure acuity for flanked and unflanked letters, centrally and peripherally, in normals and amblyopes. We find that acuity, overlap masking, and crowding each demand a minimum size or spacing for readable text. Just measuring flanked and unflanked acuity is enough for our proposed model to predict the observer's threshold size and spacing for letters at any eccentricity. We also find that amblyopia in adults retains the character of the childhood condition that caused it. Amblyopia is a developmental neural deficit that can occur as a result of either strabismus or anisometropia in childhood. Peripheral viewing during childhood due to strabismus results in amblyopia that is crowding limited, like peripheral vision. Optical blur of one eye during childhood due to anisometropia without strabismus results in amblyopia that is acuity limited, like blurred vision. Furthermore, we find that the spacing:acuity ratio of flanked and unflanked acuity can distinguish strabismic amblyopia from purely anisometropic amblyopia in nearly perfect agreement with lack of stereopsis. A scatter diagram of threshold spacing versus acuity, one point per patient, for several diagnostic groups, reveals the diagnostic power of flanked acuity testing. These results and two demonstrations indicate that the sensitivity of visual screening tests can be improved by using flankers that are more tightly spaced and letter like. Finally, in concert with Strappini, Pelli, Di Pace, and Martelli (submitted), we jointly report a double dissociation between acuity and crowding. Two clinical conditions-anisometropic amblyopia and apperceptive agnosia-each selectively impair either acuity A or the spacing:acuity ratio S/A, not both. Furthermore, when we specifically estimate crowding, we find a double dissociation between acuity and crowding. Models of human object recognition will need to

  5. Screening Preschool Children for Visual Disorders: A Pilot Study

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    Suman Adhikari, BOptom

    2013-12-01

    Full Text Available Purpose: Ocular and/or vision defects are one of the most common reasons for the referral of young children to the hospital. Vision disorders are the fourth most common disability of children and the leading cause of handicapping conditions in childhood. In preschool-age children, amblyopia and amblyogenic risk factors, such as strabismus and significant refractive errors, are the most prevalent and important visual disorders. The purpose of this pilot study was to determine the prevalence of visual disorders in preschool children in Kathmandu Valley, Nepal.Methods: Four hundred and eighty-four children attending eight preschools in Kathmandu Valley underwent detailed optometric examination. Visual acuity was assessed with either Sheridan Gardiner or Kay Picture chart monocularly. Binocularity was assessed with cover test and prism bar neutralisation. Refraction was carried out in all children. In most instances this was done without the use of a cycloplegic agent. Stereopsis was assessed with the Lang stereo test. Anterior and posterior segment abnormalities were assessed by using a pen light, hand-held slit lamp, and direct ophthalmoscope.Results: Refractive error was the most common visual disorder. Considering our criteria of refractive error for myopia ≥ 0.50 D, hyperopia ≥ 1.50 D, astigmatism ≥ 1.00 D, and anisometropia ≥ 1.00 D, the overall prevalence of refractive error in our study was 31.82%. The overall prevalence of myopia, hyperopia, and astigmatism was 24.17%, 2.48%, and 5.17%, respectively. Anisometropia was present in 1.65% of the participants, and 2%, 1.4%, and 0.2% had strabismus, amblyopia, and nystagmus, respectively.Conclusion: The relatively high prevalence of refractive error in our studied population needs more attention. The results suggest that there is a need for a large-scale community-based preschool screening program in Nepal so that affected children can be identified early and appropriate treatment can be

  6. Refractive status at birth: its relation to newborn physical parameters at birth and gestational age.

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    Raji Mathew Varghese

    Full Text Available BACKGROUND: Refractive status at birth is related to gestational age. Preterm babies have myopia which decreases as gestational age increases and term babies are known to be hypermetropic. This study looked at the correlation of refractive status with birth weight in term and preterm babies, and with physical indicators of intra-uterine growth such as the head circumference and length of the baby at birth. METHODS: All babies delivered at St. Stephens Hospital and admitted in the nursery were eligible for the study. Refraction was performed within the first week of life. 0.8% tropicamide with 0.5% phenylephrine was used to achieve cycloplegia and paralysis of accommodation. 599 newborn babies participated in the study. Data pertaining to the right eye is utilized for all the analyses except that for anisometropia where the two eyes were compared. Growth parameters were measured soon after birth. Simple linear regression analysis was performed to see the association of refractive status, (mean spherical equivalent (MSE, astigmatism and anisometropia with each of the study variables, namely gestation, length, weight and head circumference. Subsequently, multiple linear regression was carried out to identify the independent predictors for each of the outcome parameters. RESULTS: Simple linear regression showed a significant relation between all 4 study variables and refractive error but in multiple regression only gestational age and weight were related to refractive error. The partial correlation of weight with MSE adjusted for gestation was 0.28 and that of gestation with MSE adjusted for weight was 0.10. Birth weight had a higher correlation to MSE than gestational age. CONCLUSION: This is the first study to look at refractive error against all these growth parameters, in preterm and term babies at birth. It would appear from this study that birth weight rather than gestation should be used as criteria for screening for refractive error

  7. Phakic anterior chamber intraocular lens (Verisyse™ implantation in children for treatment of severe ansiometropia myopia and amblyopia: Six-month pilot clincial trial and review of literature

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    Amir Pirouzian

    2009-06-01

    Full Text Available Amir Pirouzian1,3, Kenneth C Ip2, Henry S O’Halloran31The Permanente Medical Group, Santa Clara, CA, USA; 2The Permanente Medical Group, San Francisco, CA, USA; 3Rady’s Children’s Hospital of San Diego, San Diego, CA, USAPurpose: The current study aims to evaluate both safety and efficacy of Verisyse™ (AMO, Irvine, CA phakic anterior chamber intraocular lens (IOL in the reduction of clinically significant (>-8 D myopic anisometropia in children who are noncompliant to traditional medical treatment including spectacle correction or contact lenses.Design: Retrospective interventional case series.Methods: Six anisometropic myopic pediatric patients in one practice were identified through chart-review. None of the patients were compliant with specatacle correction or contact lens wear and as a result had dense amblyopia of less than 20/400 by Snellen or Allen visual acuity (mean <20/400. All patients underwent Verisyse™ phakic IOL implantation in the more myopic eye by one surgeon (AP. Pre- and post-operative visual acuity, anterior/posterior segment examination, stereoacuity, axial biometry measurements, cycloplegic refraction, and endothelial cell counts were performed in all patients whenever feasible.Results: The age of patients ranged from 5–11 years. The mean post-operative follow-up time was six months from the time of IOL insertion. Improvement in visual acuity >6 lines was achieved in four patients (mean visual acuity of 20/70 at six months. Improvement in stereoacuity was noted in all six patients (from total mean zero seconds-arc to six-months post-operative mean of 500 seconds-arc by randot stereoacuity testing. Improvement of >2 lines of visual acuity lines was achieved in the other two patients. No patient lost any lines of visual acuity. Enhanced physical activity, coordination, and improved social interaction were noted in patients and were reported by the parents. No intra/post-operative complications were noted

  8. Measuring aniseikonia using scattering filters to simulate cataract

    Science.gov (United States)

    Wilson, Jason

    2011-12-01

    The relationship between anisometropia and aniseikonia (ANK) is not well understood. Ametropic cataract patients provide a unique opportunity to study this relationship after undergoing emmetropizing lens extraction. Because light scatter may affect ANK measurement in cataract patients, its effect should also be evaluated. The Basic Aniseikonia Test (BAT) was evaluated using afocal size lenses to produce specific changes in retinal height. Several light scattering devices were then evaluated to determine which produced effects most similar to cataract. Contrast sensitivity and visual acuity (VA) losses were measured with each device and compared to those reported in cataract. After determining the most appropriate light scattering device, twenty healthy patients with normal visual function were recruited to perform the BAT using the filters to simulate cataract. Cataract patients were recruited from Vision America and the University of Alabama at Birmingham School of Optometry. Patients between 20 and 75 years of age with at least 20/80 VA in each eye, ≥ 2D ametropia, and normal binocular function were recruited. Stereopsis and ANK were tested and each patient completed a symptom questionnaire. ANK measurements using afocal size lenses indicated that the BAT underestimates ANK, although the effect was minimal for vertical targets and darkened surroundings, as previously reported. Based on VA and contrast sensitivity loss, Vistech scattering filters produced changes most similar to cataract. Results of the BAT using Vistech filters demonstrated that a moderate cataract but not a mild cataract may affect the ANK measurement. ANK measurements on cataract patients indicated that those with ≥ 2 D ametropia in each eye may suffer from induced ANK after the first cataract extraction. With upcoming healthcare reform, unilateral cataract extraction may be covered, but not necessarily bilateral, depending on patient VA in each eye. However, a questionnaire about symptoms

  9. Prevalence and risk factors for refractive errors in the South Indian adult population: The Andhra Pradesh Eye disease study

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    Sannapaneni Krishnaiah

    2008-12-01

    Full Text Available Sannapaneni Krishnaiah1,2,3, Marmamula Srinivas1,2,3, Rohit C Khanna1,2, Gullapalli N Rao1,2,31L V Prasad Eye Institute, Banjara Hills, Hyderabad, India; 2International Center for Advancement of Rural Eye Care, L V Prasad Eye Institute, Banjara Hills, Hyderabad, India; 3Vision CRC, University of New South Wales, Sydney, NSW, AustraliaAim: To report the prevalence, risk factors and associated population attributable risk percentage (PAR for refractive errors in the South Indian adult population.Methods: A population-based cross-sectional epidemiologic study was conducted in the Indian state of Andhra Pradesh. A multistage cluster, systematic, stratified random sampling method was used to obtain participants (n = 10293 for this study.Results: The age-gender-area-adjusted prevalence rates in those ≥40 years of age were determined for myopia (spherical equivalent [SE] < −0.5 D 34.6% (95% confidence interval [CI]: 33.1–36.1, high-myopia (SE < −5.0 D 4.5% (95% CI: 3.8–5.2, hyperopia (SE > +0.5 D 18.4% (95% CI: 17.1–19.7, astigmatism (cylinder < −0.5 D 37.6% (95% CI: 36–39.2, and anisometropia (SE difference between right and left eyes >0.5 D 13.0% (95% CI: 11.9–14.1. The prevalence of myopia, astigmatism, high-myopia, and anisometropia significantly increased with increasing age (all p < 0.0001. There was no gender difference in prevalence rates in any type of refractive error, though women had a significantly higher rate of hyperopia than men (p < 0.0001. Hyperopia was significantly higher among those with a higher educational level (odds ratio [OR] 2.49; 95% CI: 1.51–3.95 and significantly higher among the hypertensive group (OR 1.24; 95% CI: 1.03–1.49. The severity of lens nuclear opacity was positively associated with myopia and negatively associated with hyperopia.Conclusions: The prevalence of myopia in this adult Indian population is much higher than in similarly aged white populations. These results confirm the previously

  10. Evaluation of central, steady, maintained fixation grading for predicting inter-eye visual acuity difference to diagnose and treat amblyopia in strabismic patients

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    Kothari Mihir

    2009-01-01

    Full Text Available Background : Diagnosis of amblyopia in preverbal strabismic patients is frequently made by binocular fixation preference (BFP testing. The reports on reliability of BFP are equivocal. This study evaluated the reliability of BFP testing in patients with horizontal strabismus. Materials and Methods: This prospective observational study included patients with manifest, horizontal, comitant deviation> 10 prism diopter (PD. Inter-eye acuity difference (IEAD was calculated by converting Snellen visual acuity to logMAR and was compared with BFP testing. The fixation behavior of the non-preferred eye was evaluated by a single investigator as central or uncentral, steady or unsteady and maintained or unmaintained. Amblyopia was defined as the IEAD of> 0.2 logMAR. Results: Of total 61 patients 36 were females and 36 had convergent squint, mean age 9.8 years. The correlation of BFP testing with IEAD was good for esotropia and exotropia. The sensitivity, specificity, positive and negative predictive value of central, steady, maintained (CSM grading was 93%, 78%, 79%, and 93% respectively. Sensitivity and negative predictive values were higher in children aged four to nine years and anisometropia> 1 diopter. The correlation between IEAD and lower grades of BFP testing was poor. Conclusions: CSM grading for BFP testing is useful for the detection of strabismic amblyopia but not useful to differentiate the depth of the amblyopia.

  11. Early screening of an infant's visual system

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    Costa, Manuel F. M.; Jorge, Jorge M.

    1999-06-01

    It is of utmost importance to the development of the child's visual system that she perceives clear focused retinal images. Furthermore if the refractive problems are not corrected in due time amblyopia may occur--myopia and hyperopia can only cause important problems in the future when they are significantly large, however for the astigmatism (rather frequent in infants) and anisometropia the problems tend to be more stringent. The early evaluation of the visual status of human infants is thus of critical importance. Photorefraction is a convenient technique for this kind of subjects. Essentially a light beam is delivered into the eyes. It is refracted by the ocular media, strikes the retina, focusing or not, reflects off and is collected by a camera. The photorefraction setup we established using new technological breakthroughs on the fields of imaging devices, digital image processing and fiber optics, allows a fast noninvasive evaluation of children visual status (refractive errors, accommodation, strabismus, ...). Results of the visual screening of a group of risk' child descents of blinds or amblyopes will be presented.

  12. Effects of different types of refractive errors on bilateral amblyopia

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    Mücella Arıkan Yorgun

    2012-12-01

    Full Text Available Objectives: Identifying effects of different types of refractiveerrors on final visual acuity and stereopsis levels inpatients with bilateral amblyopia.Materials and methods: Patients with bilateral amblyopialower than ≥1.5 D anisometropia were included. Thepatients were classified according to the level of sphericalequivalent (0-4 D and >4 D of hypermetropia, the levelof astigmatism (below and above 2D in positive cylinderand type of composed refractive error [ 4 D of hypermetropiaand 2 D of astigmatism (group III]. Initialand final binocular best corrected visual acuities (BCVAwere compared between groups.Results: The initial binocular BCVA levels were significantlylower in patients with > 4 D of hypermetropia(p=0.028, without correction after treatment (p=0.235.The initial binocular BCVA was not different betweenastigmatism groups, but final BCVA levels were significantlylower in 4-6D of astigmatism compared with 2-4D of astigmatism (p=0.001. During comparison of composedrefractive errors, only the initial binocular BCVAwas significantly lower in group I compared to group II(p=0.015. The final binocular BCVA levels were not differentbetween groups I and III (p>0.05.Conclusions: Although the initial BCVA is lower in patientswith higher levels of hypermetropia, the response ofpatients to treatment with glasses is good. The responseof patients with high levels of astigmatism seems to belimited. J Clin Exp Invest 2012; 3(4: 467-471Key words: Amblyopia, isoametropic amblyopia, hypermetropia,refractive amblyopia, visual acuity

  13. Antimetropia in a 10-year-old boy with unilateral tilted disc syndrome

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    Makino S

    2014-05-01

    Full Text Available Shinji MakinoDepartment of Ophthalmology, Jichi Medical University, Shimotsuke, Tochigi, JapanAbstract: Antimetropia is a condition in which one eye is myopic, while the fellow eye is hyperopic. This report describes a case of antimetropia associated with unilateral tilted disc syndrome. A 10-year-old boy presented with the complaint of diminished vision for distant objects in his right eye for several months. His uncorrected distance visual acuity was 0.15 in the right eye and 1.0 in the left eye. Best corrected visual acuity was 1.0, with -6.00 D/-2.00 D 170° in the right eye and +1.50 D in the left eye. The cover test revealed right esotropia and hypertropia. Bifoveal fixation was achieved using a 14 prism diopter (PD base at 220° in the right eye. Fundus examination revealed a tilted disc with inferior staphyloma in the right eye, but no abnormal findings were observed in the left eye. In addition, the patient occasionally experienced diplopia under casual viewing conditions. A cycloplegic refraction revealed -6.00 D/-2.00 D 170° in the right eye and +1.50 D/-2.00 D 5° in the left eye. Thus, prism glasses were prescribed. While wearing the prism glasses, the patient has shown no diplopia and maintains good binocular function.Keywords: amblyopia, strabismus, anisometropia, staphyloma

  14. Is the motion system relatively spared in amblyopia? Evidence from cortical evoked responses.

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    Kubová, Z; Kuba, M; Juran, J; Blakemore, C

    1996-01-01

    Visual evoked potentials (VEPs) produced by pattern reversal were compared with those elicited by onset of motion in 37 amblyopic children (20 with anisometropic amblyopia, seven with strabismic amblyopia and 10 with both anisometropia and strabismus). The amplitudes and peak latencies of the main P1 peak in the pattern-reversal VEP and of the motion-specific N2 peak in the motion-onset VEP through the amblyopic eye were compared with those through the normal fellow eye. Regardless of the type of amblyopia, the amplitude of the pattern-reversal VEP for full-field stimulation was significantly smaller and its latency significantly longer through the amblyopic eye (P central visual field (5 or 2 deg diameter) or to the peripheral field (excluding the central 5 deg), motion-onset responses were indistinguishable through the two eyes, while pattern-reversal responses always differed significantly in amplitude. These results suggest that the source of motion-onset VEPs (probably an extrastriate motion-sensitive area) is less affected in amblyopia than that of pattern-reversal VEPs (probably the striate cortex). The motion pathway, presumably deriving mainly from the magnocellular layers of the lateral geniculate nucleus, may be relatively spared in amblyopia. PMID:8746252

  15. Active training for amblyopia in adult rodents

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    Nicoletta Berardi

    2015-10-01

    Full Text Available Amblyopia is the most diffused form of visual function impairment affecting one eye, with a prevalence of 1-5% in the total world population. Amblyopia is usually caused by an early functional imbalance between the two eyes, deriving from anisometropia, strabismus, or congenital cataract, leading to severe deficits in visual acuity, contrast sensitivity and stereopsis. While amblyopia can be efficiently treated in children, it becomes irreversible in adults, as result of a dramatic decline in visual cortex plasticity which occurs at the end of the critical period in the primary visual cortex. Notwithstanding this widely accepted dogma, recent evidence in animal models and in human patients have started to challenge this view, revealing a previously unsuspected possibility to enhance plasticity in the adult visual system and to achieve substantial visual function recovery. Among the new proposed intervention strategies, non invasive procedures based on environmental enrichment, physical exercise or visual perceptual learning appear particularly promising in terms of future applicability in the clinical setting. In this survey, we will review recent literature concerning the application of these behavioral intervention strategies to the treatment of amblyopia, with a focus on possible underlying molecular and cellular mechanisms.

  16. Active training for amblyopia in adult rodents.

    Science.gov (United States)

    Sale, Alessandro; Berardi, Nicoletta

    2015-01-01

    Amblyopia is the most diffused form of visual function impairment affecting one eye, with a prevalence of 1-5% in the total world population. Amblyopia is usually caused by an early functional imbalance between the two eyes, deriving from anisometropia, strabismus, or congenital cataract, leading to severe deficits in visual acuity, contrast sensitivity and stereopsis. While amblyopia can be efficiently treated in children, it becomes irreversible in adults, as a result of a dramatic decline in visual cortex plasticity which occurs at the end of the critical period (CP) in the primary visual cortex. Notwithstanding this widely accepted dogma, recent evidence in animal models and in human patients have started to challenge this view, revealing a previously unsuspected possibility to enhance plasticity in the adult visual system and to achieve substantial visual function recovery. Among the new proposed intervention strategies, non invasive procedures based on environmental enrichment, physical exercise or visual perceptual learning (vPL) appear particularly promising in terms of future applicability in the clinical setting. In this survey, we will review recent literature concerning the application of these behavioral intervention strategies to the treatment of amblyopia, with a focus on possible underlying molecular and cellular mechanisms. PMID:26578911

  17. Asymmetric severity of diabetic retinopathy in Waardenburg syndrome: response to authors

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    Gupta A

    2012-03-01

    Full Text Available Aditi Gupta, Rajiv Raman, Tarun SharmaShri Bhagwan Mahavir Department of Vitreoretinal Services, Sankara Nethralaya, Chennai, Tamil Nadu, IndiaWe read with great interest the recent article by Kashima et al,1 in which the authors report a case of asymmetric severity of diabetic retinopathy in Waardenburg syndrome. We want to highlight some concerns regarding this report. Previous reports have described many systemic and local factors associated with the development of asymmetric diabetic retinopathy.2,3 These include myopia ≥5 D, anisometropia >1 D, amblyopia, unilateral elevated intraocular pressure, complete posterior vitreous detachment, unilateral carotid artery stenosis, ocular ischemic syndrome, and chorioretinal scarring.2,3 In any suspected case of asymmetric diabetic retinopathy, it is prudent to rule out the abovementioned factors first. In the present case, although the authors clearly mention the absence of internal carotid and ophthalmic artery obstruction on magnetic resonance angiography, it would have been more informative if the authors had also provided the refractive error, intraocular pressure, and posterior vitreous detachment status of both the eyes.Likewise, it would have been useful to note the arm-retina time and retinal arteriovenous filling time in both the eyes on fundus fluorescein angiography, which is usually used to diagnose ocular ischemic syndrome by monitoring extension of the retinal circulation time, including time of blood circulation from the arm to the retina and the retinal arteriovenous filling time.4,5 The mere absence of internal carotid obstruction on magnetic resonance angiography cannot rule out the presence of ocular ischemic syndrome because, rarely, ocular ischemic syndrome can also occur secondary to other causes, such as arteritis.6,7 Comparing the arm-retina time and retinal arteriovenous filling time on fundus fluorescein angiography in both the eyes would be more helpful to rule out ocular

  18. Phakic anterior chamber intraocular lens (Verisyse™) implantation in children for treatment of severe ansiometropia myopia and amblyopia: Six-month pilot clincial trial and review of literature

    Science.gov (United States)

    Pirouzian, Amir; Ip, Kenneth C; O’Halloran, Henry S

    2009-01-01

    Purpose: The current study aims to evaluate both safety and efficacy of Verisyse™ (AMO, Irvine, CA) phakic anterior chamber intraocular lens (IOL) in the reduction of clinically significant (>−8 D) myopic anisometropia in children who are noncompliant to traditional medical treatment including spectacle correction or contact lenses. Design: Retrospective interventional case series. Methods: Six anisometropic myopic pediatric patients in one practice were identified through chart-review. None of the patients were compliant with specatacle correction or contact lens wear and as a result had dense amblyopia of less than 20/400 by Snellen or Allen visual acuity (mean 6 lines was achieved in four patients (mean visual acuity of 20/70 at six months). Improvement in stereoacuity was noted in all six patients (from total mean zero seconds-arc to six-months post-operative mean of 500 seconds-arc by randot stereoacuity testing). Improvement of >2 lines of visual acuity lines was achieved in the other two patients. No patient lost any lines of visual acuity. Enhanced physical activity, coordination, and improved social interaction were noted in patients and were reported by the parents. No intra/post-operative complications were noted. Discussion: Irreversible or intractable amblyopia secondary to severe anisometropic myopia is a serious medical concern in the pediatric population. Failure of compliance with contact lens therapy consistently leads to visual loss. Anterior chamber phakic IOLs may provide a safe alternative in treatment of noncompliant anisometropic myopic patients who do not accept spectacle wear or contact lens therapy. Conclusion: To reduce or eliminate highly significant anisometropic myopia in children who are noncompliant with traditional medical treatment, phakic anterior chamber IOL implantation may be considered as an alternative modality of treatment. PMID:19668592

  19. Practitioners’ opinions on the presentation of ocular pathology and ametropia in patients wearing ready-made reading spectacles

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    K. C. Phillips

    2008-01-01

    Full Text Available This paper presents the findings of a study to determine optometrists’ opinions on the presentation of ocular pathology and ametropia in patients wearing ready-made reading spectacles. Ninety-seven optometrists completed a questionnaire pertaining to ametropia and ocular diseases among these patients. The questionnaire contained information regarding patient demographics, ocular pathology, ocular ametropia and the regulatory and public health aspects of ready-made readers.Ninety-five percent of respondents stated that they had seen patients with ready-made readers in their practice and 62% of these stated that they had found the presence of ocular pathology in these patients. The pathologies most commonly reported as seen by practitioners were dry eye (86% of practitioners, cataracts (80% and diabetic retinopathy (54%. In addition, 39% of practitioners reported seeing patients with anisometropia. The majority of practitioners (71% stated that they sold ready-made readers in their practice. Sixty-three percentof practitioners indicated that they would be prepared to offer a service whereby a reduced consultation fee and a pair of ready-made readers could be incorporated into an indigent “package”. An overwhelming 88% of the practitioners felt that the sale of ready-made readers should be more regulated and 74% of practitioners felt that the Professional Board for Optometry and Dispensing Opticians should be responsible for monitoring their sale. The research suggests that wearers of ready-made readers should be screened for ocular pathology, reduced visual acuity and amblyopia. Current regulations should be tightened and a public awareness education campaign should be initiated. The use of ready-made reading spectacles, in deference to an eye examination by an optometrist, appears to be largely as a result of the perceived costs of pri-vate practice combined with ignorance and apathy

  20. Surgical Results of Symmetric and Asymmetric Surgeries and Dose-Response in Patients with Infantile Esotropia

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    Nazife Sefi Yurdakul

    2015-10-01

    Full Text Available Objectives: To evaluate the results of symmetric and asymmetric surgery and responses to surgical amounts in patients with infantile esotropia. Materials and Methods: The records of patients with infantile esotropia who underwent bilateral medial rectus recession (symmetric surgery and unilateral medial rectus recession with lateral rectus resection (asymmetric surgery were analyzed. The results of the cases with symmetric (group 1 and asymmetric (group 2, successful (group 3 and failed (group 4 surgeries were compared, and responses to the amount of surgery were investigated. Results: There were no significant differences between group 1 (n=71 and group 2 (n=13 cases in terms of gender, refraction, preoperative distance deviation, anisometropia and postoperative deviation angles, binocular vision, surgical success or follow-up period (p>0.05. The rate of amblyopia, near deviation and amount of surgery were higher in group 2 cases (p0.05. The average postoperative follow-up period was 15.41±19.93 months (range, 6-98 months in group 3 cases and 40.45±40.06 months (range, 6-143 months in group 4 cases (p=0.000. No significant difference was detected in the amount of deviation corrected per 1 mm of surgical procedure between the successful cases in the symmetric and asymmetric groups (p>0.05. Conclusion: Symmetric or asymmetric surgery may be preferable in patients with infantile esotropia according to the clinical features. It is necessary for every clinic to review its own dose-response results. (Turk J Ophthalmol 2015; 45: 197-202

  1. Investigation of the change in accommodative response after successful orthoptic therapy in amblyopes%弱视儿童视力康复后调节功能变化的研究

    Institute of Scientific and Technical Information of China (English)

    刘红; 吕帆; 陈洁

    2011-01-01

    目的 调查单眼远视性屈光参差性弱视患儿视觉康复过程中视力和调节功能的康复情况,研究视力恢复后调节功能是否同步恢复。方法 横断面研究。收集正常儿童50例作为对照组,远视性屈光参差性弱视(单眼弱视)治愈儿童55例作为实验组,采用SRW-5500红外自动验光仪检查这些患儿在阅读距离为20、33、50 cm时的调节反应(双眼同时注视),采用公式——调节滞后=调节需求-调节反应,来计算调节滞后量。采用独立样本t检验、配对t检验和相关性分析对数据进行处理。结果 阅读距离为20、33、50 cm时,正常组主导眼调节滞后量分别为(0.26±0.31)、(0.12±0.02)、(0.10±0.01)D;非主导眼分别为(0.27±0.30)、(0.17±0.14)、(0.12±0.01)D。弱视者健康眼这3个距离的调节滞后量分别为(0.40±0.14)、(0.29±0.09)、(0.17±0.06)D,与正常组主导眼差异无统计学意义;弱视治愈眼调节滞后量分别为(1.66±0.47)、(1.38±0.34)、(1.16±0.34)D,比相应距离弱视者健康眼大,差异有统计学意义(t=18.731、22.764、21.020,P均<0.01)。弱视治愈眼在3个阅读距离调节反应的个体标准差分别为(0.09±0.04)、(0.09±0.02)、(0.09±0.02)D,弱视者健康眼3个距离个体标准差分别为(0.04±0.01)、(0.04±0.03)、(0.04±0.00)D,小于弱视治愈眼,差异均有统计学意义(t=10.072、10.216、22.342,P均<0.01)。结论 弱视眼视力达正常后,与对侧健康眼和正常人眼比较,其调节反应滞后量较大,同时调节反应波动也相对较大,说明远视性屈光参差性弱视眼调节功能的康复滞后于视力的提高。%Objective To investigate the recovery of accommodative function in former amblyopes with monocular hyperopic anisometropia who had undergone successful orthoptic therapy.Methods In this cross-sectional study, 55 children with monocular hyperopic anisometropia who were former

  2. A comparison of the visual status of dyslexic and non-dyslexic schoolchildren in Durban, South Africa

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    S. O. Wajuihian

    2011-12-01

    Full Text Available Background:   Reading difficulties constitute an impediment to the learning process and in the educational achievement of a child. Consequently, several studies examined the visual status of dyslexic children in the Caucasian populations. Such studies are lacking in the African populations.Aim: To determine the prevalence of vision defects and investigate if there is an association between dyslexia and vision in a South African population of dyslexic school children.  Methods:  This comparative study assessed the visual function of 62 children (31 dyslexic and 31 normally-reading children, mean age 13 ± 1.42 years and 11.90 ± 0.93 years respectively. The participants were matched for gender, race and socio-economic status. The visual functions evaluated and the techniques used were: visual acuity (LogMAR acuity chart, refraction (static retinos-copy, ocular alignment (cover test near point of convergence (RAF rule, accommodation facility (± 2 D flipper lenses, amplitude of accommodation (push-up method relative accommodation(trial lenses accommodation posture (monocular estimation technique and vergence reserves (prism bars. Results:   In the following, results are  provided for the dyslexic versus control:  Refractive errors: (hyperopia 6.5% vs 3%, (myopia 6.5% vs 6.5%, (astigmatism 10% vs 13%, (anisometropia 6.5% vs 6.5% (amblyopia 6.5% vs 0%, (remote NPC 33% vs 48% (esophoria at near 3%  vs 0% (exophoria at near 9.5% vs 0%, (accommodative infacility at near  54% vs 33%, lag of accommodation 39.28% vs 41,93%,  (poor positive fusional amplitude at near, 25% vs 16%. Only the binocular accommodative facility at near was significantly associated with dyslexia (p=0.027. Conclusion: The prevalence of vision defects was similar between the dyslexic and non-dyslexic participants, which suggest that an association between dyslexia and vision variables investigated, cannot be inferred.  This study provides a research perspective on the

  3. Prevalence of Refractive Errors among High School Students in Western Iran

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    Hassan Hashemi

    2014-01-01

    Full Text Available Purpose: To determine the prevalence of refractive errors among high school students. Methods: In a cross-sectional study, we applied stratified cluster sampling on high school students of Aligoudarz, Western Iran. Examinations included visual acuity, non-cycloplegic refraction by autorefraction and fine tuning with retinoscopy. Myopia and hyperopia were defined as spherical equivalent of -0.5/+0.5 diopter (D or worse, respectively; astigmatism was defined as cylindrical error >0.5 D and anisometropia as an interocular difference in spherical equivalent exceeding 1 D. Results: Of 451 selected students, 438 participated in the study (response rate, 97.0%. Data from 434 subjects with mean age of 16΁1.3 (range, 14 to 21 years including 212 (48.8% male subjects was analyzed. The prevalence of myopia, hyperopia and astigmatism was 29.3% [95% confidence interval (CI, 25-33.6%], 21.7% (95%CI, 17.8-25.5%, and 20.7% (95%CI, 16.9-24.6%, respectively. The prevalence of myopia increased significantly with age [odds ratio (OR=1.30, P=0.003] and was higher among boys (OR=3.10, P<0.001. The prevalence of hyperopia was significantly higher in girls (OR=0.49, P=0.003. The prevalence of astigmatism was 25.9% in boys and 15.8% in girls (OR=2.13, P=0.002. The overall prevalence of high myopia and high hyperopia were 0.5% and 1.2%, respectively. The prevalence of with-the-rule, against-the-rule, and oblique astigmatism was 14.5%, 4.8% and 1.4%, respectively. Overall, 4.6% (95%CI, 2.6-6.6% of subjects were anisometropic. Conclusion: More than half of high school students in Aligoudarz had at least one type of refractive error. Compared to similar studies, the prevalence of refractive errors was high in this age group.

  4. 综合疗法治疗儿童弱视的远期疗效分析%Analysis of Long-term Efficacy of Comprehensive Therapy for the Treatment of Amblyopia in Chil-dren

    Institute of Scientific and Technical Information of China (English)

    李凤云; 谭星平

    2013-01-01

    [目的]探讨综合疗法治疗儿童弱视的远期疗效。[方法]对557例(967眼)儿童弱视进行屈光矫正,遮盖及行红闪(激光)、光刷、多光谱、视觉刺激、视觉定位、精细目力训练等综合治疗1~5年。[结果]治愈率79.42%,有效率96.59%,屈光不正性弱视疗效优于斜视性弱视和屈光参差性弱视,弱视程度越低、年龄越小、治疗时间越长效果越好。[结论]弱视治疗效果与弱视类型、弱视程度、治疗时间、治疗年龄有关,综合疗法可以提高治愈率。%[Objective] To explore the long-term efficacy of comprehensive therapy for the treatment of ambly-opia in children .[Methods] A total of 557 pediatric patents (967 eyes) with amblyopia received comprehensive therapy such as refraction correction ,cover ,red flash light(laser) ,light brush ,multi-spectrum ,visual stimula-tion ,visual positioning and fine eyesight training for 1~5 years .[Results]The therapeutic efficacy was satisfacto-ry .The curative rate was 79 .42% and effective rate was 96 .59% .The therapeutic efficacy of ametropic amblyopia was better than that of strabismus amblyopia and anisometropia amblyopia .The lower the degree of amblyopia , the smaller the age and the longer the treatment time ,the better the results .[Conclusion]The therapeutic efficacy of amblyopia is related with the type and degree of amblyopia ,treatment time and patients'age .Comprehensive therapy can improve the curative rate .

  5. Performance of Spot Photoscreener in Detecting Amblyopia Risk Factors in Chinese Pre-school and School Age Children Attending an Eye Clinic

    Science.gov (United States)

    Mu, Yajun; Bi, Hua; Ekure, Edgar; Ding, Gang; Wei, Nan; Hua, Ning; Qian, Xuehan; Li, Xiaorong

    2016-01-01

    Purpose To evaluate the effectiveness of Spot photoscreener in detecting amblyopia risk factors meeting 2013 the American Association of Pediatric Ophthalmology and Strabismus (AAPOS) criteria in Chinese preschool and school-age children. Methods One hundred and fifty-five children (310 eyes), aged between 4 to 7 years (5.74 ± 1.2 years) underwent complete ophthalmologic examination, photoscreening, and cycloplegic retinoscopy refraction. The agreement of the results obtained with the photoscreening and retinoscopy was evaluated by linear regression and Bland-Altman plots. The sensitivity and specificity of detecting amblyopia risk factors were calculated based on the AAPOS 2013 guidelines. The overall effectiveness of detecting amblyopia risk factors was analyzed with Receiver Operating Characteristic (ROC) curves. Result The mean refractive errors measured with the Spot were: spherical equivalent (SE) = 0.70 ± 1.99 D, J0 = 0.87 ± 1.01 D, J45 = 0.09 ± 0.60 D. The mean results from retinoscopy were: SE = 1.19 ± 2.22 D, J0 = 0.77 ± 1.00 D, J45 = -0.02 ± 0.45 D. There was a strong linear agreement between results obtained from those two methods (R2 = 0.88, P<0.01). Bland–Altman plot indicated a moderate agreement of cylinder values between the two methods. Based on the criteria specified by the AAPOS 2013 guidelines, the sensitivity and specificity (in respective order) for detecting hyperopia were 98.31% and 97.14%; for detecting myopia were 78.50% and 88.64%; for detecting astigmatism were 90.91% and 80.37%; for detecting anisometropia were 93.10% and 85.25%; and for detection of strabismus was 77.55% and 88.18%. Conclusion The refractive values measured from Spot photoscreener showed a moderate agreement with the results from cycloplegic retinoscopy refraction, however there was an overall myopic shift of -0.49D. The performance in detecting individual amblyopia risk factors was satisfactory, but could be further improved by optimizing criteria based on

  6. Lente de contato em crianças: aspectos epidemiológicos Contact lens in children: epidemiological aspects

    Directory of Open Access Journals (Sweden)

    André Luiz Alves Salame

    2008-06-01

    Full Text Available OBJETIVO: Traçar o perfil epidemiológico de crianças encaminhadas para adaptação de lente de contato. MÉTODOS: Foi realizado estudo retrospectivo de pacientes registrados no Setor de lente de contato da Universidade Federal de São Paulo. Os pacientes com até 12 anos de idade foram avaliados quanto ao sexo, idade, diagnóstico, indicação e tipo de lente de contato testada na primeira consulta. RESULTADOS: Dos 73 prontuários avaliados, 34 (46,6% pertenciam a crianças do sexo masculino e 39 (53,4% a crianças do sexo feminino. A idade variou de 2 a 12 com média de 10,2 e desvio-padrão de 2,42 anos. O diagnóstico mais encontrado foi afacia em 16 (21,9% crianças, seguido de ceratocone em 14 (19,1%, leucoma em 11 (15%, anisometropia em 10 (13,7%, ametropia em 9 (12,3%, astigmatismo irregular em 7 (9,5% e ectopia lentis em 4 (5,4%. Uma criança era alta míope (1,3% e outra emétrope (1,3% que possuía desejo de usar lente de contato estética. Em relação às indicações, 52 (71,2% pacientes tinham indicação médica, 9 (12,3% indicação óptica e 12 (16,4% indicação cosmética. Foram testadas lentes em 103 olhos sendo as mais testadas a rígida gás permeável esférica em 43 (41,7%, a gelatinosa esférica em 41 (39,8% e a gelatinosa cosmética em 11 (10,6%. CONCLUSÃO: O perfil epidemiológico dos usuários de lente de contato nessa faixa etária tem como diagnóstico mais prevalente a afacia, a indicação mais freqüente a de ordem médica e a lente mais testada a rígida gás permeável esférica.PURPOSE: To describe the epidemiology of children submitted to contact lens fit. METHODS: Retrospective study of 73 children that had been submitted to contact lens fit at the "Universidade Federal de São Paulo". This study analyzed sex distribution, age, diagnosis, indications and contact lens fitted at first examination. RESULTS: 34 children (46.6% were male and 39 (53.4% female, aged between 2 and 12 years with mean of 10.2 and

  7. Immediate versus Delayed Sequential Bilateral Cataract Surgery: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Monali S Malvankar-Mehta

    Full Text Available Immediately sequential bilateral cataract surgery (ISBCS, the cataract surgery that is performed in both eyes simultaneously, is gaining popularity worldwide compared to the traditional treatment paradigm: delayed sequential bilateral cataract surgery (DSBCS, the surgery that is performed in each eye on a different day as a completely separate operation. ISBCS provides advantages to patients and patients' families in the form of fewer hospital visits. Additionally, patients enjoy rapid rehabilitation, lack of anisometropia - potentially reducing accidents and falls, and avoid suboptimal visual function in daily life. The hospital may benefit due to lower cost.To perform a systematic review and meta-analysis to evaluate ISBCS and DSBCS.Databases including MEDLINE, EMBASE, BIOSIS, CINAHL, Health Economic Evaluations Database (HEED, ISI Web of Science (Thomson-Reuters and the Cochrane Library were searched.Not applicable.Literature was systematically reviewed using EPPI-Reviewer 4 gateway. Meta-analysis was conducted using STATA v. 13.0. Standardized mean difference (SMD and 95% confidence intervals (CI were calculated and heterogeneity was assessed using I2 statistics. Fixed-effect and random-effect models were computed based on heterogeneity. Meta-analysis was done by instrument used to calculate utility score.In total, 9,133 records were retrieved from multiple databases and an additional 128 records were identified through grey literature search. Eleven articles with 3,657 subjects were included for analysis. Our meta-analysis results indicated significant improvement in post-operative utility score using TTO, EQ5D, HUI3, VF-7, and VF-14 and a non-significant improvement using Catquest questionnaire for both surgeries. For ISBCS versus DSBCS, utility-specific fixed-effect model provided an overall SMD of the utility score using the TTO method as 0.12 (95% CI: -0.15, 0.40, EQ5D as 0.14 (95% CI: -0.14, 0.41, HUI3 as 0.12 (95% CI: -0.15, 0.40, VF

  8. A cross-sectional survey on refractive errors in students 4-18 years old in Guanxian county,Shandong province%山东省冠县4~18岁学生屈光不正横断面研究

    Institute of Scientific and Technical Information of China (English)

    吴建峰; 毕宏生; 胡媛媛; 吴慧; 孙伟; 吕太亮; 王兴荣

    2014-01-01

    Objective To examine the prevalence of refractive errors among preschool children and schoolchildren in Guanxian county,Shandong province.Methods Using a random cluster sampling in a cross-sectional school-based study design,children ranging in age from 4 to 18 years were selected from kindergartens,primary schools,and junior and senior high schools in Guanxian county.All children underwent a complete ocular examination including measurement of uncorrected (UCVA) and best corrected visual acuity (BCVA),auto-refractometry under cycloplegia and ophthalmic examination.The prevalence rates of refractive error and its association with age and gender were analyzed by a bivariate regression model.Results Of 3 112 eligible children,cycloplegic refraction was completed on 3 111 and the visual acuity of 3 094 was successfully tested.The overall prevalence of myopia was 31.3%(95%CI:29.7%-33.0%).Myopia was associated with older children [OR:1.45 (95%CI:1.41-1.50); P<0.01],female gender [OR:1.45(95%CI:1.41-1.50); P<0.01] and children in urban areas [OR:2.54 (95%CI:2.11-3.07) ; P<0.01].The prevalence of high myopia,astigmatism and anisometropia was 1.4% (95%CI:1.0%-1.8%),32.4% (95%CI:30.8%-34.0%) and 6.2% (95%CI:5.4%-7.1%),respectively.All prevalences were associated with older children (P<0.01) but not gender (P>0.05).The prevalence of astigmatism and anisometropia was also associated with children in urban areas (P<0.01).The overall prevalence of hyperopia was 8.2%(95%CI:7.2%-9.2%),and the trend decreased with age [OR:0.72(95%CI:0.68-0.76); P<0.01].UCVA was 20/40 or worse in the better eye in 675(21.8%) children,and 20/200 or worse in the better eye in 85(2.7%) children.UCVA≤20/40 in one or both eyes was found in 880(28.4%) children,with undercorrected refractive error as the cause in 837(95.1%) children.Conclusion Visual impairment in students 4-18 years of age in Guanxian county was mainly attributed to