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BACKGROUND: Amblyopia is a neurological deficit in binocular vision that affects 3% of the population and is the result of disruptions in early visual development. OBJECTIVE: In this study, we used a visual perceptual learning system for the short-term treatment of children with ametropic amblyopia and evaluated the clinical efficacy of this system in terms of visual plasticity. METHODS: We conducted a retrospective analysis of the clinical data of 114 children (228 eyes) with refractive amblyopia, who were aged 6.51 ± 1.51 years. Prior to the treatment, we evaluated all children with amblyopia using the visual information processing test. We determined the type of amblyopic defect according to the type of amblyopia, corrected visual acuity, and advanced visual function test results. Based on the type of defect, each child with amblyopia was given short-term visual perception training for 10 days. Finally, we compared the results of visual acuity and visual information processing tests before and after the treatment. RESULTS: The best-corrected visual acuity of patients was better after 10 days of visual training than that before training (P< 0.05). The perceptual eye position after training improved with statistically significant differences in horizontal and vertical perceptual eye position (both P< 0.05) compared to that before training. The number of amblyopic children without suppression in both eyes was 81 cases (71.1%) after training which was higher than that (65 cases, or 57.0%) before training, with a statistically significant difference (P< 0.05). Binocular fine stereopsis and dynamic stereopsis improved after training with a statistically significant difference (both P< 0.05). CONCLUSION: In this study, it was found that patients with amblyopia showed visual plasticity. Moreover, continuous visual perceptual learning improved the best-corrected visual acuity and recovered stereopsis in children with refractive amblyopia.
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Ambliopía , Niño , Humanos , Ambliopía/terapia , Estudios Retrospectivos , Agudeza Visual , Percepción Visual , OjoRESUMEN
PURPOSE: To investigate the prevalence and type of high astigmatism among children aged 3 to 6 years in Guangxi, a relatively undeveloped province in western China, and to examine the correlation between astigmatism and visual acuity. METHODS: Children aged 3 to 6 years in Nanning, the capital of Guangxi Province, participated in a population-based survey using a cluster random sampling technique. Eye examinations included autorefraction, visual acuity measurements, and assessments of the external eye, anterior segment, media, and fundus. Data for the right eyes were analyzed. RESULTS: Among the 2304 children examined, the overall prevalence of high astigmatism (≥1.25 diopters by noncycloplegic SureSight autorefraction) was 12.7% (95% confidence interval, 11.3 to 14.0%). The age-specific prevalences of high astigmatism in 3-, 4-, 5-, and 6-year-old children were 13.8, 13.2, 12.9, and 8.1%, respectively. The prevalence of high astigmatism did not vary with age or gender (p > 0.05). The majority of cases of high astigmatism were with-the-rule astigmatism (82.9%), followed by against-the-rule (12.6%) and oblique (4.5%) astigmatism. A linear correlation was found between astigmatism magnitude and visual acuity (logMAR acuity = 0.068 + 0.055 × astigmatism) in all participants. Multiple linear regression analysis further showed that the correlation of astigmatism with visual acuity was magnitude dependent (ß = 0.240). When with-the-rule astigmatism was used as a reference group, against-the-rule astigmatism (ß = 0.137) and oblique astigmatism (ß = 0.154) were closely correlated with visual acuity. CONCLUSIONS: High astigmatism was moderately prevalent among children aged 3 to 6 years in Guangxi Province. With-the-rule astigmatism was the dominant form of astigmatism. Magnitude- and orientation-dependent correlations of astigmatism with visual acuity were confirmed.
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Astigmatismo/epidemiología , Astigmatismo/clasificación , Astigmatismo/fisiopatología , Niño , Preescolar , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Agudeza Visual/fisiologíaRESUMEN
OBJECTIVE: To investigate the prevalence, type and distribution of astigmatism in children with amblyopia. METHODS: A total of 2023 children with amblyopia (aged 4-11 years, 3657 eyes) were recruited. The prevalence of astigmatism was investigated. RESULTS: Of the 3657 amblyopic eyes, 91.9% presented astigmatism (≥0.5 D). The proportion of eyes with astigmatism decreased with the increasing age. Compound hyperopic astigmatism was the most common type of astigmatism (38.8%) and its prevalence increased with the increasing age in children with amblyopia. Astigmatism with the rule was the most common (90.1%) in the axial distribution test. There were statistical significances in the axial distribution of astigmatism in different age groups. Statistical significances were also found in the degree, type and axis of astigmatism among the children with mild, moderate and severe amblyopia (P<0.05). CONCLUSIONS: The prevalence of astigmatism in children with amblyopia is high but is reduced with age. The age and the degree of amblyopia might be influential factors in the distribution of astigmatism.
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Ambliopía/epidemiología , Astigmatismo/epidemiología , Ambliopía/complicaciones , Astigmatismo/complicaciones , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Masculino , PrevalenciaRESUMEN
OBJECTIVE: To evaluate the changes of ultrastructure and viability in the rabbit corneal epithelial flap after Epi-LASIK (epiploic laser in-situ keratomileusis) surgery and its effect on keratocyte apoptosis and proliferation of peripheral corneal epithelium (out of corneal epithelial flap). METHODS: Fifty-eighty eyes of 29 New Zealand rabbits were used, Epi-LASIK was performed in 28 eyes and Photorefractive keratectomy (PRK) was carried out in 24 eyes. treated-eyes were randomly divided into four groups and were sacrificed at 1, 3, 5, 7 days after surgery, six eyes without treatment were served as blank controls. Histological structure from The specimens of Epi-LASIK and controls eyes were assessed by light, transmission electron microscopy; epithelial cells viability were assessed by enzyme-histochemistry and Immunohistochemistry staining (proliferating cell nuclear antigen, PCNA) were performed to detect proliferation of peripheral corneal epithelial cells. Apoptotic cells were detected by TUNEL assay (TdT-mediated dUTP nick-end labeling) from the specimens of Epi-LASIK and PRK. RESULTS: The study from Transmission electron microscopy demonstrated that epithelial flap separated by KM5000D type epikeratome retained its typical stratification and integrity and the basement membrane including lamina densa and lamina lucida were compaginated with stroma. The expression of ATP enzyme, G-6-P enzyme from epithelial flap to peripheral epithelium of Epi-LASIK-treated eyes were (79%, 58%, 69%, 86%), (79%, 63%, 77%, 97%) at 1, 3, 5, 7 days after surgery respectively. There was no statistically significant difference in the cell Viability and the number of PCNA in peripheral epithelial cells among four Epi-LASIK groups and control group. At 1 day after surgery, no difference in TUNEL positive cells were seen between specimens of Epi-LASIK (3.429 +/- 1.693) and PRK (3.796 +/- 1.998); At 3, 5, 7 days, there was a significant difference in the number of keratocyte apoptosis in PRK compared to Epi-LASIK specimens. CONCLUSIONS: Epithelial flap separated by KM5000D type epikeratome retained its typical stratification and integrity. The flap keeps high viability and no peripheral epithelial cell proliferation and therefore it may play a role in the inhibition of keratocyte apoptosis.