RESUMO
BACKGROUND/PURPOSE: To investigate the clinical features and visual outcomes of acute optic neuritis in adult patients. METHODS: We prospectively collected ninety-nine adult patients, who were found to have acute optic neuritis between 2005 and 2007 at National Taiwan University Hospital. A total of 30 cases, aged ranging from 21 to 55 years old (average 36.4 ± 9.9), that followed up at least 6 months were enrolled in our study. Baseline clinical features and visual function results were analyzed. RESULTS: The mean follow-up period was 15.6 months. Twenty three (76.7%) cases were female. Twenty-seven cases were unilateral involved, one was simultaneously bilateral involved and two was sequentially bilateral involved. In total 33 affected eyes, ocular or periocular pain was noted in 14 eyes (69.7%). Optic disc swelling was noted in 5 eyes (15.2%). A total of 6 cases had recurrent episodes, and two of them were diagnosed with multiple sclerosis thereafter. At 6-month follow up, 24 eyes (72.7%) had good visual recovery (better than 20/40). Only 2 eyes (6%) had severe visual loss (<20/1000). Optic disc pale was detected in 72.7% of the eyes during follow up. CONCLUSION: Visual recovery was observed in most eyes with acute optic neuritis, although disc pale detectable. Patients with recurrent optic neuritis had worse visual outcome. There was a low association of optic neuritis with multiple sclerosis in our patients.
Assuntos
Neurite Óptica/fisiopatologia , Acuidade Visual , Doença Aguda , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
PURPOSE: To evaluate the relationship among single nucleotide polymorphisms (SNPs) in steroidogenesis enzyme genes, serum levels of sex steroids, and high myopia in Taiwanese male and female populations. METHODS: A campus-based sample of 283 cases (145 males and 138 females) with high myopia and 280 controls (144 males and 136 females) with low myopia or emmetropia was studied. Estradiol, progesterone, and testosterone levels were determined using enzyme-linked immunosorbent assay kits. We genotyped six SNPs within five steroidogenesis enzyme genes (17 alpha-hydroxylase/17,20 lyase [CYP17A1], 3 beta-hydroxysteroid dehydrogenase [HSD3B1], 17 beta-hydroxysteroid dehydrogenase 1 [HSD17B1], steroid-5-alpha-reductase, alpha polypeptide 2 [SRD5A2], and aromatase [CYP19A1]) using polymerase chain reaction-restriction fragment length polymorphism methods. Student's t-tests, χ(2) tests, logistic regression, multifactor dimensionality reduction (MDR) methods, and ANOVA were used to determine significance. RESULTS: An MDR analysis corroborated the synergistic genotype association and demonstrated that synergistic interaction between rs6203 (HSD3B1), rs10046 (CYP19A1), and sex might confer susceptibility to high myopia (p=0.019). In both male and female subjects, levels of testosterone were significantly higher in cases than in controls; in male subjects, the levels of estradiol were significantly higher and those of progesterone were significantly lower in cases (all p-values <0.001). The rs605059 (HSD17B1), with sex-gene interaction, showed association with estradiol levels in males (p=0.035) and testosterone levels in females (p=0.027). CONCLUSIONS: Testosterone levels correlate with high myopia, and interaction of steroidogenesis enzyme genes and sex may be a modulating factor in sex hormone metabolism and high-myopia risk.
Assuntos
Povo Asiático , Estradiol/genética , Miopia/genética , Esteroides/sangue , Testosterona/genética , 17-Hidroxiesteroide Desidrogenases/sangue , 17-Hidroxiesteroide Desidrogenases/genética , 3-Hidroxiesteroide Desidrogenases/sangue , 3-Hidroxiesteroide Desidrogenases/genética , Adulto , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Estradiol/sangue , Estradiol Desidrogenases/sangue , Estradiol Desidrogenases/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Miopia/sangue , Miopia/epidemiologia , Polimorfismo de Nucleotídeo Único , Fatores Sexuais , Esteroide 17-alfa-Hidroxilase/sangue , Esteroide 17-alfa-Hidroxilase/genética , Taiwan/epidemiologia , Testosterona/sangueRESUMO
This review provides insights into the mechanism underlying the pathogenesis of myopia and potential targets for clinical intervention. Although the etiology of myopia involves both environmental and genetic factors, recent evidence has suggested that the prevalence and severity of myopia appears to be affected more by environmental factors. Current pharmacotherapeutics are aimed at inhibiting environmentally induced changes in visual input and subsequent changes in signaling pathways during myopia pathogenesis and progression. Recent studies on animal models of myopia have revealed specific molecules potentially involved in the regulation of eye development. Among them, the dopamine receptor plays a critical role in controlling myopia. Subsequent studies have reported pharmacotherapeutic treatments to control myopia progression. In particular, atropine treatment yielded favorable outcomes and has been extensively used; however, current studies are aimed at optimizing its efficacy and confirming its safety. Furthermore, future studies are required to assess the efficacy of combinatorial use of low-dose atropine and contact lenses or orthokeratology.
Assuntos
Olho/efeitos dos fármacos , Miopia/tratamento farmacológico , Visão Ocular/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Olho/metabolismo , Olho/fisiopatologia , Humanos , Miopia/metabolismo , Miopia/fisiopatologia , Transdução de Sinais , Resultado do TratamentoRESUMO
OBJECTIVE: To investigate the association of genetic polymorphisms in the dermatan sulfate proteoglycan 3 (DSPG3), lumican (LUM), and decorin (DCN) genes (component genes of the sclera) with high myopia susceptibility in Taiwanese people. DESIGN: Prospective case-control study. PARTICIPANTS: Hospital clinic-based samples of 120 unrelated patients with extremely high myopia were studied. One hundred thirty-seven unrelated emmetropic individuals served as controls. METHODS: Four, 8, and 4 single nucleotide polymorphism (SNPs) were genotyped within the DSPG3, lumican, and decorin genes, respectively, using direct DNA sequencing. Pairwise linkage disequilibrium, haplotype analysis, adjusted logistic regression, and multifactor dimensionality reduction (MDR) methods were used to determine significant associations. MAIN OUTCOME MEASURES: The association of haplotypes at the lumican gene with high myopia development. RESULTS: The lumican gene SNP rs3759223:T-->C demonstrated a significant association with high myopia (P = 2.83 x 10(-4)). Four lumican SNPs showed significant linkage disequilibrium and formed a haplotype block. Sliding window haplotype analyses revealed that the block consisting of rs3759223 and rs3741834 showed significant goodness of fit (global P = 1.0725 x 10(-6)). Haplotype-specific tests showed that the C-C and T-C haplotypes were associated significantly with high myopia, with odds ratios (95% confidence intervals) of 19.32 (2.55-146.54) and 0.69 (0.46-1.04), respectively. rs3759223 and rs3741834 are in a putative regulatory element of the lumican gene, which influences fibrillogenesis of scleral collagen fibers and the development of myopia. The results of an MDR analysis corroborated the single-locus association and suggested a significant 2-locus interaction model composed of SNPs rs2300588 and rs3741834 in the lumican gene. CONCLUSIONS: Genetic variation in the regulatory domains of the lumican gene, where both rs3759223 and rs3741834 are located, are associated with high myopia susceptibility among the Han Chinese, making this region worthy of further investigation.
Assuntos
Proteoglicanas de Sulfatos de Condroitina/genética , Predisposição Genética para Doença , Haplótipos/genética , Sulfato de Queratano/genética , Miopia Degenerativa/genética , Polimorfismo de Nucleotídeo Único/genética , Povo Asiático/genética , Estudos de Casos e Controles , Decorina , Proteínas da Matriz Extracelular/genética , Feminino , Humanos , Lumicana , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteoglicanas/genética , Proteoglicanos Pequenos Ricos em Leucina , Taiwan/epidemiologiaRESUMO
PURPOSE: The membrane frizzled-related protein (MFRP) has been proposed as a probable candidate gene for extreme hyperopia and nanophthalmos, which are factors for angle-closure glaucoma. The purpose of our study was to investigate whether there are significant associations between angle-closure glaucoma and sequence variants in the MFRP gene reported previously in Taiwanese subjects. METHODS: Genomic DNA was collected from 63 subjects with angle-closure glaucoma and 66 age-matched and gender-matched controls without angle-closure glaucoma. Three sequence variants were detected by polymerase chain reaction (PCR) and direct sequencing in all of the cases and controls. RESULTS: None of the three sequence variants showed a significant result in terms of association with disease. The pairwise linkage disequilibrium (LD) mapping confirmed that these alleles have a comparatively strong LD index greater than 0.7 for D' and greater than 0.4 for r(2) at these polymorphisms. However, we found there were no statistical associations between any of the three sequence variants located on MFRP and angle-closure glaucoma. CONCLUSIONS: In our pilot study, variations that we tested in MFRP were not associated with the development of acute angle-closure glaucoma in Taiwanese subjects.
Assuntos
Predisposição Genética para Doença , Glaucoma de Ângulo Fechado/genética , Proteínas de Membrana/genética , Estudos de Casos e Controles , Feminino , Haplótipos , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNARESUMO
OBJECTIVE: To investigate vitreous levels of reactive oxygen species (ROS) in patients with proliferative diabetic retinopathy (PDR) and analyze ROS levels among different groups of PDR patients. DESIGN: Retrospective case-control study. PARTICIPANTS: Thirty-nine eyes of 39 patients with PDR and 16 eyes of 16 non-PDR patients (control group) that underwent primary vitrectomy for complications of PDR and other conditions (control group), with a follow-up time > or = 12 months. METHODS: Proliferative diabetic retinopathy patients were classified into 3 groups according to the extent of fibrovascular proliferation: (1) no or focal adhesions at < or =3 sites (n = 17); (2) > or =1 broad adhesions or vitreous-retinal adhesions around disc, macula, and arcade (n = 12); and (3) vitreous-retinal attachment extending to the periphery or no posterior vitreous detachment with or without retinal detachment (RD) (n = 10). The control group (n = 16) contained non-PDR patients. Vitreous samples were obtained during measurement of vitrectomy and vitreous levels of ROS by luminol-enhanced chemiluminescence assay. MAIN OUTCOME MEASURES: Reactive oxygen species levels were recorded as mean (+/- standard deviation) chemiluminescence counts per 10 seconds. Correlations of vitreous levels of ROS among the 3 PDR groups and anatomic prognosis were evaluated. Multiple linear regression analysis of selective potential risk factors was performed to investigate the main determinants of ROS levels. RESULTS: Vitreous ROS levels were significantly higher in patients with PDR (125.76+/-351.72 chemiluminescence counts per 10 seconds) than in control patients (0.37+/-0.72 chemiluminescence counts per 10 seconds; P<0.0001). Reactive oxygen species levels were 1.86+/-1.63 (group 1), 24.47+/-22.68 (group 2), and 457.94+/-597.01 (group 3); the difference among groups was significant (P = 0.001). Regression analysis indicated that only patient grouping (according to the severity of fibrovascular proliferation) had a strong dependent association with ROS levels (P = 0.001). Final anatomic results revealed that recurrent untreatable RD occurred in 3 patients of group 3, who also had the highest ROS levels. CONCLUSIONS: Reactive oxygen species levels were significantly elevated in the vitreous fluid of PDR patients, and patients with a more advanced clinical PDR appearance had higher ROS levels. These findings suggest an association between ROS and the pathogenesis of PDR. Reactive oxygen species might be correlated with PDR severity.
Assuntos
Retinopatia Diabética/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Corpo Vítreo/metabolismo , Idoso , Estudos de Casos e Controles , Retinopatia Diabética/fisiopatologia , Retinopatia Diabética/cirurgia , Progressão da Doença , Feminino , Humanos , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , VitrectomiaRESUMO
BACKGROUND/PURPOSE: Taiwan has a very high prevalence rate of myopia. We retrospectively studied the influence of myopia on the progression of visual field (VF) loss in primary open-angle glaucoma (POAG) patients. METHODS: We studied 515 POAG patients for a minimum follow-up period of 5 years. VF examination was performed with Humphrey perimeter, 30-2 SITA standard program, every 6 months. A point-wise numerical comparison was applied to judge the VF changes. Test points showing more than 1.0 dB of sensitivity loss in mean defect were identified. A location was considered to have progression if it was detected on two consecutive visits. Progression of VF loss was confirmed if three or more test points deteriorated. Multivariate logistic regression was used to evaluate the association between progression of VF loss and various risk factors. RESULTS: There were 262 cases. Progression of VF loss occurred in 57 eyes (21.8%) during the 5-year follow-up period. Logistic regression revealed that the deterioration was associated with older age, higher mean intraocular pressure, larger vertical cup-to-disc ratio, and greater myopic refraction status. The incidence of VF loss progression was 15.1% in the group of eyes with myopia less than -3 D, 10.5% in the group with -3 D to -6 D, 34.4% in the group with -6 D to -9 D, and 38.9% in the group with myopia greater than -9 D. CONCLUSION: POAG patients with myopia greater than -6 D had a greater progression of VF loss.
Assuntos
Glaucoma de Ângulo Aberto/complicações , Miopia/complicações , Baixa Visão/etiologia , Campos Visuais/fisiologia , Adolescente , Adulto , Idoso , Progressão da Doença , Feminino , Seguimentos , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Miopia/epidemiologia , Miopia/fisiopatologia , Prevalência , Prognóstico , Refração Ocular , Estudos Retrospectivos , Taiwan/epidemiologia , Fatores de Tempo , Baixa Visão/fisiopatologia , Acuidade Visual , Testes de Campo Visual , Adulto JovemRESUMO
PURPOSE: To investigate the role of heredity in determining refractive variables, anterior corneal curvature, and anterior corneal aberrations. METHODS: Thirty-three monozygotic and 10 dizygotic twin pairs were enrolled in this study. Corneal curvature, corneal astigmatism, and corneal topography were obtained from computerized videokeratoscope. The CTView program was used to compute anterior corneal aberrations from corneal height data of the videokeratoscope. Correlation analysis was performed to investigate the symmetry of the refractive error, corneal curvature, corneal astigmatism, and anterior corneal aberrations between right and left eyes of each twin pair. Heritability (h2) of these parameters was also calculated. RESULTS: Positive correlations were noted between right and left eyes for spherical power, total astigmatism, mean corneal curvature, and corneal astigmatism. In monozygotic twins, vertical coma, secondary vertical coma, spherical aberration, and secondary spherical aberration were moderately correlated. In dizygotic twins, vertical coma, secondary horizontal coma, and spherical aberration were moderately correlated. In unrelated controls, secondary vertical coma, secondary horizontal coma, and secondary spherical aberration were moderately correlated. Root-mean-square (RMS) of higher order aberrations (3rd to 6th orders), RMS of spherical aberration, and RMS of coma were moderately correlated between right and left eyes in all three groups. Heritability of spherical aberration, RMS of spherical aberration, and corneal astigmatism (h2 = 0.56, 0.44, and 0.46) were greater than those of refractive power, corneal curvature, and other higher order aberrations. CONCLUSIONS: These results suggest that corneal astigmatism and spherical aberration possess a greater genetic predisposition than those of other refractive errors and higher order aberrations.
Assuntos
Astigmatismo/genética , Córnea/patologia , Doenças em Gêmeos/genética , Erros de Refração/genética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Idoso , Topografia da Córnea , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeAssuntos
Membrana Basal/cirurgia , Fóvea Central/cirurgia , Miopia/cirurgia , Retinosquise/cirurgia , Adulto , Idoso , Corantes/administração & dosagem , Feminino , Humanos , Verde de Indocianina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Perfurações Retinianas/prevenção & controleRESUMO
Myopia is highly prevalent among schoolchildren in East Asia and Singapore; however, its prevalence has been gradually increasing, and the number of population-based and non-population-based studies assessing this trend has increased in the past 10 years. Although the causes of this high prevalence in East Asia and Singapore remain poorly identified, related studies have discussed the associated risk factors. We summarize the data concerning the prevalence rates reported in related studies and discuss the most crucial risk factors among these schoolchildren.
Assuntos
Miopia/epidemiologia , Refração Ocular , Criança , Ásia Oriental/epidemiologia , Humanos , Prevalência , Fatores de Risco , Singapura/epidemiologiaRESUMO
PURPOSE: To study the relationships between single nucleotide polymorphisms (SNPs) of lumican, decorin, and DSPG3 genes and high myopia. METHODS: One hundred and twenty adult patients with high myopia (< -10.0 D) and 137 controls were used to study the relationships between the decorin, lumican, and DSPG genes and high myopia. All subjects were free of ocular diseases, other than myopia, as well as of other systemic genetic diseases. Genotyping was performed by direct sequencing after PCR amplification of chromosomal DNA. Allele frequencies were tested for Hardy-Weinberg disequilibrium. The chi(2) or Fisher test was conducted to investigate the genotypic and allelic distribution between the high myopia and control groups. RESULTS: The genotyping success rate was 100%. Univariate analysis revealed significant differences between patients and control subjects with respect to one of the SNPs (rs3759223, C->T) of the lumican gene, with a p value of 0.000283. There was no significant relationship between other SNPs of lumican, decorin, and DSPG genes and high myopia. CONCLUSIONS: Our results indicate that an SNP (rs3759223), which is located in the promoter region of the lumican gene, may be worth further investigation to determine its association with development of high myopia.
Assuntos
Região 5'-Flanqueadora , Povo Asiático/genética , Proteoglicanas de Sulfatos de Condroitina/genética , Predisposição Genética para Doença , Sulfato de Queratano/genética , Miopia/fisiopatologia , Polimorfismo de Nucleotídeo Único , Adulto , Sequência de Bases , Estudos de Casos e Controles , Decorina , Proteínas da Matriz Extracelular/genética , Feminino , Genótipo , Humanos , Lumicana , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Miopia/genética , Regiões Promotoras Genéticas , Proteoglicanas/genética , Índice de Gravidade de Doença , Proteoglicanos Pequenos Ricos em Leucina , TaiwanRESUMO
PURPOSE: To study the relationships between single nucleotide polymorphisms (SNPs) of extracellular matrix, matrix metalloproteases (MMPs), tissue inhibitors of MMPs, and other glaucoma-associated genes and acute primary angle closure glaucoma (PACG). METHODS: We extracted DNA samples from 78 adult patients with acute PACG and 86 control subjects to study the relationships between these specific genes and acute PACG. Genotyping was performed for 35 genes by the GenomeLab SNPstream genotyping system after PCR amplification of chromosomal DNA. The association between these genetic polymorphisms and risk of primary PACG was estimated by chi2 and logistic regression. RESULTS: The genotyping success rate was 99%. Genotyping for the MMP9 site (rs2664538) was significantly different between the two groups (p=0.000001) and the odds ratio was 2.586 (95% CI: 1.715-3.898, p<0.00001). However, there were no associations of SNPs to other genes in patients with acute PACG. CONCLUSIONS: Our results reveal that SNP rs2664538, which is located at the MMP9 gene, is likely to be associated with acute PACG.
Assuntos
Povo Asiático/genética , Predisposição Genética para Doença , Glaucoma de Ângulo Fechado/genética , Metaloproteinase 9 da Matriz/genética , Polimorfismo de Nucleotídeo Único , Doença Aguda , Idoso , Feminino , Genótipo , Homozigoto , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , TaiwanRESUMO
PURPOSE: To report a case of type I Gaucher's disease with rare presentation of fundus abnormalities in long-term observation. DESIGN: Observational case report. METHODS: This 53-year-old Taiwanese woman suffered from type I Gaucher's disease for 12 years, with initial presentation of hepatoslpenomegaly in 1992. RESULTS: At that time, poor vision with unusual macular change and peripheral retinal vessel leakage was also noted. She received a complete ophthalmic examination at the initial visit and again 12 years later in 2003. She was treated with imiglucerase injection during the last 4 years. However, her visual acuity was 10/200 in both eyes. The macular and peripheral retinal degenerative change progressed after 12 years. CONCLUSIONS: Fundus changes associated with Gaucher's disease are uncommon. We should not neglect the possibility of retinal involvement and progression in these patients.
Assuntos
Fundo de Olho , Doença de Gaucher/complicações , Doenças Retinianas/etiologia , Permeabilidade Capilar , Feminino , Angiofluoresceinografia , Seguimentos , Doença de Gaucher/diagnóstico , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/uso terapêutico , Humanos , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Doenças Retinianas/diagnóstico , Doenças Retinianas/tratamento farmacológico , Vasos Retinianos/patologiaRESUMO
BACKGROUND AND PURPOSE: This study investigated the prevalence and distribution of anisometropia in Taiwanese schoolchildren using nationwide data from refractive surveys performed in 1995 and 2000. METHODS: Complete survey data was obtained for 11,175 students in 1995 and 10,878 students in 2000. The refractive status of each student was measured using an autorefractometer under cycloplegia and rechecked with retinoscopy. The difference in refractive status between each participant's eyes was determined. Chi-squared statistic was used to assess the difference between the 2 surveys. Multiple linear regression was used to determine the trend and effects of covariates. RESULTS: Most of the schoolchildren (77.6% in 1995, 71.9% in 2000) were not anisometropic. Most of the anisometropic differences were in the range 0.5 to 1.0 D (14.1% in 1995 vs 17.9% in 2000). About 6% of schoolchildren in 1995 and 7.0% in 2000 had anisometropic differences in the range from -1.0 to -2.0 D. Fewer than 4% of students had a level of anisometropia greater than 2.0 D (2.7% vs 3.2%, respectively). The prevalence of anisometropia and the extent of anisometropic difference both increased with age and with maximal myopic refraction (both p < 0.0001). Both the prevalence and extent of anisometropia showed significant differences between the 2 surveys (both p < 0.0001). CONCLUSIONS: Most of the Taiwanese schoolchildren surveyed were non-anisometropic. The prevalence and amount of anisometropia were significantly increased from 1995 to 2000. The mechanisms responsible for these increases have not been determined, but may be related to increase of myopic refraction.
Assuntos
Anisometropia/epidemiologia , Adolescente , Fatores Etários , Criança , Feminino , Humanos , Masculino , Prevalência , Análise de Regressão , Taiwan/epidemiologia , Fatores de TempoRESUMO
PURPOSE: To evaluate changes of the central anterior chamber depth, cilio-angular cross-sectional surface area, and intraocular pressure in rabbit eyes undergoing application of the scleral suction ring during lamellar refractive surgery. METHODS: Thirty eyes of 30 rabbits were used in the study. The eyes were assigned to one of the following five surgical groups: group 1, no application of the suction ring; group 2, suction for 2 minutes; group 3, suction for 1 minute; group 4, suction for 20 seconds; and group 5, suction for 10 seconds. Ultrasound biomicroscopy (UBM) was performed to determine tomographic features, including central anterior chamber depth, cross-sectional surface area of the ciliary body, and chamber angle structure before and 10 minutes, 1 hour, 2 hours, 1 day, 2 days, 1 week, and 2 weeks after surgery. Intraocular pressure was also measured at each of these time points. RESULTS: Swelling of the ciliary body occurred in groups 2 to 5 of eyes from 10 minutes up to 1 day after the operation, and its severity was positively related to the duration of suction. Shallowness of the chamber angle was positively related to swelling. All UBM-detectable changes became insignificant compared with baseline values at 2 days after the operation. No significant change was found in the central anterior chamber depth and intraocular pressure during the 2-week postoperative observation period. CONCLUSIONS: Transient change in the ciliary body and the chamber angle occurred frequently after application of the scleral suction ring during lamellar refractive surgery in rabbit eyes. Its severity was positively related to the duration of suction. Swelling of the ciliary body corresponded with the shallowness of the chamber angle without alteration of the corneal-lenticular distance and intraocular pressure.
Assuntos
Câmara Anterior/diagnóstico por imagem , Corpo Ciliar/diagnóstico por imagem , Procedimentos Cirúrgicos Oftalmológicos/instrumentação , Procedimentos Cirúrgicos Refrativos , Esclera , Sucção/efeitos adversos , Doenças da Úvea/diagnóstico por imagem , Animais , Câmara Anterior/patologia , Corpo Ciliar/patologia , Pressão Intraocular , Masculino , Coelhos , Fatores de Tempo , Ultrassonografia , Doenças da Úvea/etiologiaRESUMO
PURPOSE: To assess quantitatively the biometric optic components and its relationship with refractive status in preterm school children with diode laser-treated threshold retinopathy of prematurity (ROP). METHODS: A prospective, cross-sectional study in which ultrasound biometric measurement of optic components and cycloplegic refraction were performed on 24 consecutive preterm children with diode laser-treated threshold ROP at the age of 9 years. The study results were compared with 1021 age-matched full-term control children from a national survey. RESULTS: The eyes with laser-treated ROP showed statistically significantly thicker lens (3.94 versus 3.39 mm), steeper vertical corneal curvature (7.47 versus 7.67 mm) and shallower anterior chamber depth (ACD) (2.91 versus 3.58 mm) than age-matched full-term controls, but no difference in axial length (23.32 versus 23.24 mm). The laser-treated eyes had a mean spherical equivalent (SE) of -4.49 D compared with mean SE of -0.44 D in controls. Of 46 eyes studied, 93% of eyes were myopic and 28.3% with high myopia (<-6.0 D) compared with the 32% prevalence of myopia in controls. In preterm children, younger gestational age tended to correlate with shallower ACD (r = 0.352) and thicker lens (r = -0.298); lower birth weight tended to correlate with shallower ACD (r = 0.372) and steeper cornea (r = 0.360). CONCLUSIONS: There were higher prevalence and greater magnitude of myopia in preterm children. The significantly thicker lens, steeper corneal curvature and shallower anterior chamber depth are the major factors contributing to the development of myopia in preterm school children with laser-treated threshold ROP.
Assuntos
Biometria/métodos , Córnea/cirurgia , Terapia a Laser/métodos , Lasers Semicondutores/uso terapêutico , Miopia Degenerativa/epidemiologia , Retinopatia da Prematuridade/cirurgia , Criança , Pré-Escolar , Córnea/fisiopatologia , Estudos Transversais , Técnicas de Diagnóstico Oftalmológico , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Miopia Degenerativa/diagnóstico , Miopia Degenerativa/etiologia , Prevalência , Estudos Prospectivos , Refração Ocular , Retinopatia da Prematuridade/complicações , Retinopatia da Prematuridade/fisiopatologia , Taiwan/epidemiologia , Fatores de TempoRESUMO
PURPOSE: To compare myopic progression rates in Taiwanese schoolchildren between urban and rural areas. METHODS: Several longitudinal studies of myopic progression were performed in urban and rural areas. Five primary schools, four junior high schools, and two senior high schools were selected from both urban and rural areas. Ages ranged from 7 to 18 years. The refractive state of each student was measured with an autorefractometer under cycloplegia. RESULTS: Mean myopic progression in primary school children (ages 7 to 12) in the urban areas was around 0.20 D/year for boys and 0.27 D/year for girls. The mean myopic progression rate in urban children from primary to junior high school age (ages 10 to 15) was 0.43 D/year for boys and 0.50 D/year for girls, faster than that in rural children (0.24 and 0.31 D/year, respectively). The average progression rate was fastest in children in junior high school (ages 13 to 15), around 0.45 D/year in urban areas and 0.28 D/year in rural areas. In senior high schools (ages 16 to 18), myopic progression slowed to 0.17 D/ year in boys and 0.33 D/year in girls. Myopic progression in all groups was faster in myopic eyes than in emmetropic or hyperopic eyes. CONCLUSIONS: The average myopic progression in urban areas was greater than that in rural areas. Environmental factors such as urban development and academic grade level may be important contributing factors to myopic progression.
Assuntos
Miopia/fisiopatologia , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Distribuição por Idade , Criança , Progressão da Doença , Feminino , Humanos , Masculino , Refração Ocular/fisiologia , Distribuição por Sexo , Inquéritos e Questionários , Taiwan/epidemiologiaRESUMO
PURPOSE: To evaluate the refractive status and optical components in school age children born prematurely and to examine the risk factors associated with refractive errors. METHODS: The participants were a cohort of children aged 7 to 9 years with gestational age less than 35 weeks or birth weight less than 1500 g. The participants' neonatal histories were reviewed; their refractive status and optical components were measured. The study results were compared with the results of age-matched children from a national survey. RESULTS: Of the 108 children studied, 48 (44%) had retinopathy of prematurity (ROP); 29 (27%) had ROP ≥ stage 3. Compared with the control subjects, the study cases showed higher prevalence of myopia (48% vs. 29%), hyperopia (23% vs. 15%), and astigmatism (73% vs. 41%). Common ocular features included shallow anterior chamber depth (ACD), thick lenses, and steep corneal curvature. The hyperopic cases had the shortest axial length (AL), whereas the myopia cases had significantly shallower ACD and greater LT. Those with a history of ROP had more prominent changes in the anterior segment. Generalized estimating equations showed that refractive errors could be predicted by a combination of optical components. CONCLUSIONS: In children born prematurely, the development of myopia is mainly influenced by anterior segment components, whereas hyperopia is mainly attributable to short AL. Astigmatism is primarily cornea-related. A combination of various optical components results in complicated refractive outcomes. The presence of ROP may be associated with significantly shorter ACD, thicker lens, and higher myopia and astigmatism. (ClinicalTrials.gov number, NCT01045616.).
Assuntos
Câmara Anterior/patologia , Córnea/patologia , Cristalino/patologia , Nascimento Prematuro/fisiopatologia , Erros de Refração/fisiopatologia , Retinopatia da Prematuridade/fisiopatologia , Biometria , Criança , Feminino , Seguimentos , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Masculino , Refração Ocular , Estudos RetrospectivosRESUMO
PURPOSE: To explore the possible influence of ocular growth, refractive error and age on the crystalline lens in school-age children. METHODS: A Taiwan nationwide survey of myopia performed in 2006 was used to determine the prevalence and severity of myopia and the changes in ocular components. A total of 11,656 students were enrolled, including 5,390 boys and 6,266 girls, with ages ranging from 7 to 18 years. Refractive status was measured with an autorefractometer with the subject under cycloplegia. Lens thickness, anterior chamber depth, and axial length were measured with biometric ultrasound. RESULTS: Data revealed that the crystalline lens became thinner between the ages of 7 and 11. Subsequent increases in the lens thickness correlated with age and the stability of myopia. This phenomenon was found not only in myopic eyes, but also in emmetropic and hyperopic eyes. The changes in anterior chamber depth inversely correlated with the changes in the lens. In school-age children, the ratio of lens/axial length was found to be significant: approximately 0.147 in the emmetropic group. However the ratio was seen to increase with age. The ratio of anterior segment/axial length was found to be approximately 0.3 in emmetropic eyes among all age groups and less than 0.3 in the myopic eyes of schoolchildren. CONCLUSIONS: Lens thinning appeared to be compensatory in nature with respect to the increased axial length of normal eye growth. Myopic eye growth induces the lens to compensate by becoming much thinner. The change in anterior chamber depth corresponded inversely with lens thickness.
Assuntos
Envelhecimento/fisiologia , Olho/crescimento & desenvolvimento , Hiperopia/fisiopatologia , Cristalino/fisiopatologia , Miopia/fisiopatologia , Adolescente , Câmara Anterior/diagnóstico por imagem , Câmara Anterior/fisiopatologia , Criança , Feminino , Humanos , Hiperopia/epidemiologia , Cristalino/diagnóstico por imagem , Masculino , Miopia/epidemiologia , Prevalência , Refração Ocular/fisiologia , Taiwan/epidemiologia , UltrassonografiaRESUMO
PURPOSE: To examine the genetic and environmental factors for myopia at the family level, as well as risk factors such as ocular measurements and environmental covariates at the individual level, by analysis of myopic twin data. METHODS: A myopic twin study was conducted on participants from the 2000 Guinness World Records for twins in Taiwan. A total of 130 participants comprising 58 twin pairs and 13 siblings were recruited. The generalized estimating equation approach was used to evaluate the covariate effects. A Bayesian linear mixed model was then used to estimate the heritability. RESULTS: Pearson's intrapairwise correlation coefficients for ocular refraction and its components were higher among monozygotic twins than among dizygotic twins. The significance of sex suggested that women are more myopic than men. Both axial length and anterior chamber depth were significant factors associated with myopia. The results also showed that people with higher education levels were more likely to have a higher degree of myopia. After accounting for genetic and environmental effects and other covariates, the estimate of heritability of myopia was as high as 0.306. CONCLUSIONS: After adjusting for environmental covariates, heritability still plays a decisive genetic role in the development of myopia.