Perception of first-order grating acuity and second-order spatial contrast sensitivity in anisometropia amblyopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To study the perception of first-order grating acuity and second-order spatial contrast sensitivity in patients with monocular anisometropia amblyopia.METHODS:A total of 715 children(715 eyes)diagnosed as monocular anisometropia amblyopia in our hospital from January 2018 to December 2022 were collected as amblyopia group, and 745 children(745 eyes)with normal corrected visual acuity were collected. The best corrected visual acuity(BCVA), first-order grating acuity and/or second-order spatial contrast sensitivity were measured, repectively. The perception ability of amblyopia patients to first-order grating acuity and second-order spatial contrast sensitivity were analyzed.RESULTS:There were significant differences between amblyopia group and normal control group in the perception of first-order grating acuity(11.58±6.10 vs. 20.27±3.47, P<0.001)and second-order spatial contrast sensitivity(0.33±0.16 vs 0.12±0.04, P<0.001). And there were significant differences between mild-to-moderate amblyopia and severe amblyopia patients in first-order grating acuity(12.10±6.23 vs. 8.13±3.70, P<0.001)and second-order spatial contrast sensitivity(0.32±0.16 vs. 0.37±0.17, P<0.05).CONCLUSION: The first-order and second-order visual pathway of the cerebral cortex in children with monocular anisometropia amblyopia have different degrees of damage. The injury of severe amblyopia is more serious than that of mild-to-moderate amblyopia.

Pediatric visual acuity examinations and vision care

The visual system of newborn infants is not like that of adults. Both ocular and neural structures essential for vision will undergo anatomical and physiological changes as maturation process. The maturation of all visual systems occurs relatively rapidly in normal children. So, early examination of visual acuity is critical for normal visual funciton achievement. Visual acuity in preverbal children can be assessed using several techniques, such as fixation and following behavior under both monocular and binocular conditions, the optokinetic nystagmus technique, preferential looking, visual evoked potential, and recognition acuity using a vision chart. Most clinicians consider the standard technique of recognition acuity to be the gold standard for visual acuity assessments, 20/20 vision should be achieved by 7 years of age. Significant refractive error, a high degree of hyperopia, myopia, or astigmatism may result in not only blurred vision, but also strabismus and amblyopia. Therefore, early vision screening is very valuable. Subjective and objective refractive techniques are standard for detecting significant refractive errors in children and are available under either non-cycloplegic or cycloplegic conditions. Amblyopia is the most common cause of vision loss in children and young adults, defining as a reduction of best-corrected visual acuity due to the interruption of normal visual development during the so-called sensitive period. If the problem is not identified until the sensitive period is complete, the vision loss is permanent. Visual impairment in childhood affects all aspects of the child's development. Earlier treatment is associated with better outcomes. Of course, patient compliance and parental support are the most important factors contributing to treatment success.

Pediatric visual acuity examinations and vision care

The visual system of newborn infants is not like that of adults. Both ocular and neural structures essential for vision will undergo anatomical and physiological changes as maturation process. The maturation of all visual systems occurs relatively rapidly in normal children. So, early examination of visual acuity is critical for normal visual funciton achievement. Visual acuity in preverbal children can be assessed using several techniques, such as fixation and following behavior under both monocular and binocular conditions, the optokinetic nystagmus technique, preferential looking, visual evoked potential, and recognition acuity using a vision chart. Most clinicians consider the standard technique of recognition acuity to be the gold standard for visual acuity assessments, 20/20 vision should be achieved by 7 years of age. Significant refractive error, a high degree of hyperopia, myopia, or astigmatism may result in not only blurred vision, but also strabismus and amblyopia. Therefore, early vision screening is very valuable. Subjective and objective refractive techniques are standard for detecting significant refractive errors in children and are available under either non-cycloplegic or cycloplegic conditions. Amblyopia is the most common cause of vision loss in children and young adults, defining as a reduction of best-corrected visual acuity due to the interruption of normal visual development during the so-called sensitive period. If the problem is not identified until the sensitive period is complete, the vision loss is permanent. Visual impairment in childhood affects all aspects of the child's development. Earlier treatment is associated with better outcomes. Of course, patient compliance and parental support are the most important factors contributing to treatment success.

Changes of visual development in critical period produced by monocular chronic atropinization in rats / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the changes of visual development produced by monocular atropinization in rats. METHODS: Twenty normal SD rats were randomly divided into two groups: control group ( n = 10 ) and atropinization ( experimental) group ( n=10 ) . All the left eyes were selected as the experimental eyes, and the right eyes served as the normal eyes. The left eyes in atropinization group was produced by 1% atropine, 3 times a day and the right eyes in control group was treated with normal saline, 3 times a day. The flash visual evoked potentials ( F-VEP ) and retinoscopy refraction of the rats'both eyes were detected at five time points:0, 7, 14, 21, and 28d after atropinization, respectively. After 28d, six rats were randomly selected from both groups and each group had three rats. The expression of the c- fos mRNA was observed in both visual cortexes. Another six rats were chosen for the same test after 2d dark environment with 2h light later. The expression of c-fos mRNA was detected again. RESULTS: After 14d anisometropia was observed in experimental group, the difference was 3. 9D ( P 0.0 5 ) , F-VEP P1 wave of the rats left in experimental group was reached to 88. 9±1. 889ms at 21d, there was statistical difference compared with the right eye ( PCONCLUSION: In the critical period of visual development, monocular chronic atropine in rats can form anisometropia, may delay the transmission of the optic nerve, hinder the normal development of the visual cortex. Monocular atropinization in rats can be used as the model of anisometropia.

Relationship between monocularly deprivation and amblyopia rats and visual system development

OBJECTIVE@#To explore the changes of lateral geniculate body and visual cortex in monocular strabismus and form deprived amblyopic rat, and visual development plastic stage and visual plasticity in adult rats.@*METHODS@#A total of 60 SD rats ages 13 d were randomly divided into A, B, C three groups with 20 in each group, group A was set as the normal control group without any processing, group B was strabismus amblyopic group, using the unilateral extraocular rectus resection to establish the strabismus amblyopia model, group C was monocular form deprivation amblyopia group using unilateral eyelid edge resection + lid suture. At visual developmental early phase (P25), meta phase (P35), late phase (P45) and adult phase (P120), the lateral geniculate body and visual cortex area 17 of five rats in each group were exacted for C-fos Immunocytochemistry. Neuron morphological changes in lateral geniculate body and visual cortex was observed, the positive neurons differences of C-fos expression induced by light stimulation was measured in each group, and the condition of radiation development of P120 amblyopic adult rats was observed.@*RESULTS@#In groups B and C, C-fos positive cells were significantly lower than the control group at P25 (P0.05), C-fos protein positive cells level of group B was significantly lower than that of group A (P<0.05). The binoculus C-fos protein positive cells level of groups B and C were significantly higher than that of control group at P35, P45 and P120 with statistically significant differences (P<0.05).@*CONCLUSIONS@#The increasing of C-fos expression in geniculate body and visual cortex neurons of adult amblyopia suggests the visual cortex neurons exist a certain degree of visual plasticity.

Effect of dark rearing on development of visual sense and proteomics of visual cortex in growing rat / 中华实验眼科杂志

Background Previous study on critical period plasticity in local cortical circuits primarily was only to test the role of some proteins in visual cortex on visual development based on the existed neural signals expression system,but whole containing proteins analysis in cortical circuits is lack.To perform a whole containing proteins analysis has an important significance for critical period plasticity study.Objective This study was to investigate the influence of dark rearing on visual sense and proteomics in visual cortex for growing rat.Methods Two SD female rats were fed in two cages together with 12 newborn rats on the same day respectively,and half number of newborn rats were exchanged each other from first day after delivering and marked by eartipping.The newborn rats in a cage were bred in the dark environment for 40 days,and newborn rats in other cage were bred in the nature environment as controls.The blink response of rats to nearby object was examined and compared between the two groups of rats.Then three rats from two cages were sacrificed respectively and bilateral primary visual cortex tissue was isolated.Proteomics in rat primary visual cortex was detected by two-dimensional electrophoresis and mass spectrometry and the result was checked from database.Then the survival rats in the dark environment returned to the nature environment for 10 days,and the blink response of rats to nearby object were compared with that of agematched rats in the natural environment.The use and care of experimental rats followed the instruction of Ethic Committee of Nankai University.Results The blink response of rats was (0.33 ± 0.35) times in the dark environment for 40-day group,and that in the natural environment for 40-day group was (6.42±0.68) times,with a significant difference between them (t =24.38,P＜0.01).After returned to natural environment for 10 days,the blink response times of rats were less than those of the natural environment group ([5.00±1.22] times vs.[6.11±0.59]times),but this change was not statistically significant (t =2.09,P＞0.05).Two-dimensional electrophoresis and mass spectrometry assay revealed that 36 different proteins in visual cortex were found in the dark-feed rats compared with the natural environment rats,including 26 loss proteins and 10 extra proteins.Among the different proteins,Eps 15 homology domain-containing protein-3 (EHD3),tubulin alpha-1A chain and 2 ',3 '-cyclic-nucleotide 3 ' phosphordiesterase were the known proteins.Conclusions Dark rearing cause reversible visual loss in critical period plasticity newborn rat,and the change of proteomics in visual cortex is probably an affecting factor.

Sweep pattern visual evoked potential acuity in visual developing children / 中华实验眼科杂志

BackgroundSweep pattern visual evoked potential(SPVEP) acuity,as an objective detective technique of visual function,can be used to measure visual acuity in children and uncooperative adults.Recent studies have shown that the amplitude-logarithm of the visual angle (A-LogVA) function regression method was more accurate than the amplitude-spatial frequency (A-SP)function regression method in evaluating SPVEP acuity.Objective This study was to explore the clinical use of SPVEP acuity in visual developing children and compare the evaluating the SPVEP acuity of children between A-SP function regression method and A-LogVA function regression method.Methods Twenty-six eyes of 26 asthenopic children with age range of 3-12 years and 31 age-matched normal children were enrolled in this study.SPVEP acuity was recorded with GT-2000 NV ( GUOTE MEDICAL APPARATUS LTD,China) using sinusoidally modulated horizontal gratings of 10 different spatial frequencies from 0.99 to 12.89 cpd as stimulus.The responses were averaged and displayed through discrete Fourier transformations (DFT) on the monitor display.SPVEP acuity was estimated by using both the SPVEP A-SP function regression method and the SPVEP A-LogVA function regression method.The LogMAR chart was used to acquire LogMAR visual acuity.ResultsIn the normal group,the correlation coefficient between LogMAR visual acuity and acuity calculated by the A-SP function regression method was 0.600 (P＜0.01).The correlation coefficient between LogMAR visual acuity and acuity calculated by the A-LogVA function regression method was 0.733 ( P＜0.01 ).The ANOVA of the LogMAR acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were 113.173 (P＜0.01 ),which indicated that there were significant difference among all of subjects.The differences of the mean values of LogMAR visual acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were respectively 0.40±0.02,0.26 ±0.02 and 0.14 ± 0.02.In the amblyopia group,the correlation coefficient between LogMAR visual acuity and acuity calculated by the A-SP function regression method was 0.134 (P =0.515 ).The correlation coefficient between LogMAR visual acuity and acuity calculated by the A-LogVA function regression method was 0.456 ( P＜0.05 ).The ANOVA of the LogMAR acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were 3.433 (P＜0.05),indicating that there were significant difference among all of subjects.The differences of the mean values of LogMAR visual acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were 0.07±0.05,0.12±0.05 and 0.05 ±0.01 respectively.Conclusions SPVEP can evaluate the visual acuity in children,although SPVEP acuity may overestimate or underestimate acuity in comparison with different LogMAR visual acuities.The amplitude-LogVA function regression method is more accurate in extrapolating SPVEP acuity.

Expression of ciliary neurotrophic factor in visual cortex of form deprivation amblyopia cat and its effect / 中华实验眼科杂志

Background Researches demonstrated that ciliary neurotrophic factor (CNTF) can enhance survival and promote differentiation of neutron.Meanwhile,CNTF also is thought to play an important role in the development of visual pathway.But,less studies are reported in the relationship of CNTF and form deprivation amblyopia.Objective This study was to investigate the expressions of CNTF in visual cortex area 17 in form deprivation amblyopia model.Methods Twelve 4-week-old cats were randomized into normal group and form deprivation amblyopia group.Monocular form deprivation amblyopic models were established in 6 cats by eyelids suture method.Pattern visual evoked potential(P-VEP) was recorded to evaluate the amblyopic models 16 weeks later following the eyelids suturing.Then,bilateral visual cortex tissue was incised at a vertical in sagittal axis fashion to prepare the section.Nissl staining was used to detect the morphologies of neurons.Expression of CNTF in Ⅰ-Ⅵ layers of visual cortex area 17 was located and quantified by immunochemistry.The positive cell number and gray scale for CNTF were calculated and compared between two groups.The use of the animals complied with Regulations for the Administration of Affairs Coucerning Experimental Animals by State Science and Technology Commission.Results Compared with the normal group,P-VEP amplitude was significantly reduced (6.11 ±1.56 μV vs.11.42±t.92 μV) and latency was significantly prolonged(75.77±9.83 ms vs.58.56±7.17 ms) in the form deprivation amblyopia group (t=5.272,3.464,P＜0.05).Nissl staining showed that the number of neurons in the form deprivation amblyopia group was less than that in the normal group.In the form deprivation amblyopia group,neurons became shrinkage and turned round,cytoplasmic processes get shortened,and the nucleus became small.The number of Nissl bodies was decreased.lmmunochemistry showed the positive neutrons for CNTF in Ⅰ-Ⅵ layers of visual cortex area 17 in hoth normal cats and model cats with the more positive cells in Ⅱ-Ⅳ layers.Compared with the normal group,the positive cell number for CNTF was significantly reduced in Ⅱ-Ⅳ layers of visual cortex area 17 in the form deprivation amblyopia group (Ⅱ layer:95.93±8.24 vs.116.25±6.52;I layer:102.65±7.45 vs.125.23±8.21;Ⅳ layer:l10.65±6.85 vs.139.54±4.26) (t=4.737,4.989,8.773,P＜0.05).In addition,the gray scale of CNTF positive cells was significantly lower in Ⅱ-Ⅳ layers of visual cortex area 17 in the form deprivation amblyopia group than that the normal group (Ⅱ layer:106.98 ± 8.86 vs.138.65 ± 6.38 ; Ⅲ layer:109.56 ± 8.69 vs.149.59 ±8.55;Ⅳ layer:l16.65 ±9.52 vs.155.76±9.87) (t=7.105,8.043,6.986,P＜0.05).Both CNTF positive cell number and gray scale in Ⅰ,Ⅴ,Ⅵ layers of visual cortex area 17 had no significant differences between two groups (P＞0.05).Conclusions Form deprivation in critical period of a new born animal may lead to distributing abnormality of CNTF in visual cortex,which maybe play a role in the development of form deprived amblyopia.

Diffusion tensor imaging(DTI) and its application in visual development and amblyopia research / 眼科研究

Diffusion tensor imaging(DTI) is an efficient and noninvasive tool to investigate the characteristics and functions of white matter fiber tracts,and it can be used to study the relationship between the structure and function in the nervous system,the plasticity and damage repair of visual development,abnormalities of the white matters that relate to the visual pathways.Recently,the quantification of white matter fiber tracts from the lateral geniculate bodies to the occipital lobe visual cortex using DTI offers morphological information for the function and structure of the white matters during visual development.Some studies attempt to compare the DTI outcomes and tractography between amblyopic children and normal children so as to better display the variations of optic radiation in children with amblyopia,and to evaluate the relationship between structure and function of the white matters.DTI becomes an important supplementary research approach in these fields.This paper reviews the application of DTI in visual development and amblyopic eyes.

Diferenças na detecção de frequências espaciais e radiais em crianças / Differences in detection of spatial and radial frequencies in children

O objetivo deste estudo foi comparar curvas de sensibilidade ao contraste para estímulos radiais (FSCr) e grades senoidais (FSC) de 0,25, 0,5, 1 e 2 cpg em crianças de 6 a 13 anos. Foram mensurados limiares de contraste para 40 crianças, utilizando o método psicofísico da escolha forçada e níveis baixos de luminância. Todas estavam livres de doenças oculares e tinham acuidade visual normal. Os resultados mostraram que a sensibilidade das crianças foi maior para grades senoidais (FSC) do que para estímulos radiais (FSCr). Esses resultados sugerem que esses estímulos podem ser processados por áreas visuais distintas.

The aim of this work was to compare contrast sensitivity curves for radial (rCSF) and sine-wave gratings (CSF) stimuli of 0.25, 0.5, 1 and 2 cpd in 6 to 13 year-old-children. It was measured the contrast thresholds of 40 children using the psychophysical forced-choice method and low luminance levels. All children were free of identifiable ocular diseases and had normal acuity. The results showed that contrast sensitivity of the children was higher for spatial frequencies (CSF) than radial frequencies (rCSF). The results suggest that these stimuli can be processed by different visual cortical areas.

Desenvolvimento ocular / Ocular development

O conhecimento do desenvolvimento da visão é fundamental ao clínico/pediatra. Os aspectos da maturação visual devem ser considerados, não só para orientação, mas também para a prevenção e tratamento de perdas visuais.O desenvolvimento de cada porção ocular se dá individualmente, em prazos variáveis, constituindo, assim, possibilidades visuais, muitas vezes, bastante abaixo do que se poderia esperar pelo aspecto externo do olho. A observação isolada de cada parte principal da maturação ocular pode facilitar a compreensão e a orientação semiológica para determinada idade e capacidade funcional da criança.

Sensibilidade ao contraste de freqüências radiais em crianças de 4 a 7 anos e adultos / Radial frequency contrast sensitivity in children of 4 to 7 years old and adults

O objetivo deste trabalho foi medir a sensibilidade ao contraste para freqüências radiais (FSCr) de 0,25 a 2 cpg em crianças (4 a 7 anos) e adultos. Foram estimados limiares de contraste para 25 participantes (vinte crianças e cinco adultos jovens), utilizando o método psicofísico da escolha forçada. Os participantes apresentavam acuidade visual normal. Os resultados mostraram que as curvas (FSCr) de crianças de 4 a 7 anos melhoraram de forma significativa com a idade. Os resultados mostraram ainda que a FSCr de crianças de 7 anos é mais baixa do que a de adultos jovens. Estes resultados sugerem que o desenvolvimento da percepção visual de contraste para estímulos radiais ocorre gradualmente se prolongando além dos 7 anos.

The aim of this work was to measure contrast sensitivity for radial frequencies (rCSF) in the range between 0.25-2 cpd in children (4 to 7 years of age) and young adults. Contrast thresholds were estimated for 25 participants (twenty children and five adults) using the psychophysical forced-choice method at low luminance levels. All the cts participants had normal acuity. The results showed that the curves (rCSF) of the 4, 5, 6 and 7 years old improved significantly with age. The results also showed that the rCSF for 7 year old children was lower than in young adults. These results suggest that the development of contrast sensitivity for radial stimuli increases gradually even after turning 7 years old.

Percepção de padrões concêntricos em crianças de 8 a 13 anos / Perception of concentric patterns in children of 8 to 13 years old

O objetivo deste trabalho foi mensurar a função de sensibilidade ao contraste de padrões circulares concêntricos (FSCr) com freqüências radiais de 0,25; 0,5; 1,0 e 2,0 cpg em crianças (8-9, 10-11 e 12-13 anos) e adultos jovens. Foram estimados limiares de contraste para 40 participantes (30 crianças e 10 adultos jovens) utilizando o método psicofísico da escolha forçada e nível baixo de luminância. Todos os participantes apresentavam acuidade visual normal e se encontravam livres de doenças oculares identificáveis. Os resultados mostraram que as curvas de FSCr de crianças de 8-9, 10-11 e 12-13 anos melhoram de forma significativa com a idade. Os resultados mostraram ainda que a FSCr de crianças de 12-13 anos é mais baixa do que a de adultos jovens. Estes resultados sugerem que o desenvolvimento da percepção visual de estímulos circulares concêntricos ocorre gradualmente se prolongando além dos 12-13 anos.

The aim of this study was to measure the function of contrast sensitivity to concentric circular patterns (rCSF) with radial frequencies of 0.25, 0.5, 1.0 and 2.0 cpd in children (8-9, 10-11 and 12-13 years of age) and young adults. Contrast thresholds were measured in 40 participants (thirty children and ten young adults) using the psychophysical forced-choice method and low luminance level. All participants were free from identifiable ocular diseases and had normal acuity. The results showed that curves for rCSFs of 8-9, 10-11 and 12-13 years old improved significantly with age. The rCSFs for the 12-13 years old was lower than those of adults. It is suggested that the development of visual perception in concentric circular stimuli increases gradually beyond 12-13 years of age.

El objetivo de este trabajo fue mensurar la función de sensibilidad al contraste de padrones circulares concéntricos (FSCr) con frecuencias radiales de 0,25; 0,5; 1,0 y 2,0 cpg en niños (8-9, 10-11 y 12-13 años) y adultos jóvenes. Fueron estimados umbrales de contraste para 40 participantes (30 niños y 10 adultos jóvenes) utilizando el método psicofísico de la elección forzada y nivel bajo de luminancia. Todos los participantes presentaban acuidad visual normal y estaban libres de enfermedades oculares identificables. Los resultados mostraron que las curvas de la FSCr de niños de 8-9, 10-11 y 12-13 años mejoran de forma significativa con la edad. Los resultados mostraron aún que la FSCr de niños de 12-13 años es más baja que la de adultos jóvenes. Estos resultados sugieren que el desarrollo de la percepción visual de estímulos circulares concéntricos ocurrí gradualmente prolongándose después de los 12-13 años.

Desenvolvimento normal do comportamento visual em lactentes de um a seis meses de idade: suporte informacional para pais / Normal visual development in 1 to 6 month old infants: informational support for parents

O presente estudo tem por objetivo apresentar material de suporte informacional e instrumental sobre o desenvolvimento visual normal até o sexto mês de vida destinado aos pais. Foi realizada revisão da literatura sobre pressupostos teóricos na área do desenvolvimento infantil que abordam o comportamento visuomotor de lactentes, a importância da família e da intervenção oportuna. O material informativo foi gerado a partir da experiência cotidiana de trabalho de uma equipe multiprofissional composta por alunos e pesquisadores da Universidade Estadual de Campinas e da Universidade Federal de São Carlos, os quais realizam o acompanhamento do desenvolvimento visuomotor de lactentes no primeiro trimestre de vida.

This paper presents informational and instrumental support to parents regarding the normal visual development of their children from birth to the sixth month of life. The theoretical presuppositions of the children’s development related to infant visuomotor behavior and family’s role in timely intervention were reviewed. Informational material was developed from daily work experiences of a multi-professional group compound of students and researchers from the Universidade Estadual de Campinas (UNICAMP) and Universidade Federal de São Carlos (UFSCar) who follow up the visuomotor development of infants in the first three months of life.

Effects of MK-801 on rat F-VEPs during the critical period of visual development / 第三军医大学学报

Objective To investigate the effects of MK-801 on the rat F-VEPs during the critical period of visual plasticity.Methods We performed the F-VEPs examination in the normal Long Evans rats and the MK-801 treated rats on their postnatal days 14 and 28.Results After eye-opening,the latency of F-VEP main wave became shorter(P

Effect of CSPGs degradation on flash visual evoked potential in rat visual cortex / 第三军医大学学报

Objective To investigate the effects of chondroitin sulfate proteoglycans (CSPGs) degradation induced by chondroitinase ABC (ChABC) on the rat flash visual evoked potential (F-VEP) around the end of the critical period of visual development.Methods A total of 30 Long Evans rats were randomly divided into 3 groups according to their age of 14,21 and 35 d.Then in each group,5 animals served as CSPGs degradation model induced by ChABC microinjection into 5 sites of the rat cortex [750 nL (48 U/ml) for 1 site,for 2 times at a 3-day interval],and the other 5 rats served as normal control and received normal saline microinjection.Immunofluorescence microscopy and laser scanning confocal microscopy were used to determine the establishment of animal model.F-VEPs were evaluated in 7 d after first microinjection.Results In the normal rats,the latency of F-VEP main wave became shorter with the increase of their age,the number was [(63.5?10.1),(50.8?6.4),(44.9?6.3) ms,P