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1.
Invest Ophthalmol Vis Sci ; 62(13): 5, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34636878

RESUMO

Purpose: To examine the interactions between accommodation and overstimulation of the retinal ON- and OFF-pathways, and their association with changes in choroidal thickness (ChT) and vascularity. Methods: Optical coherence tomography imaging of the choroid of twenty young adults (ages 25 ± 5 years) was performed before and after a series of 30-minute-long viewing tasks, including reading a bright text on dark background (ON-pathway overstimulation) and dark text on bright background (OFF-pathway overstimulation), and a control task of viewing a movie with unbiased ON-/OFF-pathway activation. The viewing tasks were performed with relaxed, and 5 diopter (D) accommodation (induced by soft contact lenses) demands. Both reading texts were matched for the mean luminance (35 cd/m2), luminance contrast (87%), and letter size (approximately 11.8 arc minutes). The change in ChT from baseline associated with contrast polarity and accommodation was examined using linear mixed model analysis. Results: The subfoveal ChT decreased significantly by -7 ± 1 µm with 5 D accommodation compared with relaxed accommodation (-3 ± 1 µm; P < 0.001), and by -9 ± 1 µm with OFF-pathway compared with ON-pathway overstimulation (-4 ± 1 µm; P = 0.002) and the control condition (-2 ± 1 µm; P < 0.001). Overstimulation of the OFF-pathway, but not the ON-pathway, resulted in a significantly greater choroidal thinning compared with the control condition, both at relaxed (-7 ± 1 µm; P = 0.003) and 5 D (-11 ± 1 µm; P = 0.005) accommodation levels. Similar changes were also observed for macular total, stromal, and luminal ChT. Conclusions: Retinal OFF-pathway stimulation enhanced the choroidal thinning associated with accommodation, thereby providing a potential mechanism that involves accommodation and the retinal OFF-signaling pathway, linking near work and myopia.


Assuntos
Acomodação Ocular/fisiologia , Comprimento Axial do Olho/diagnóstico por imagem , Corioide/diagnóstico por imagem , Miopia/diagnóstico por imagem , Refração Ocular/fisiologia , Tomografia de Coerência Óptica/métodos , Adulto , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Valores de Referência , Adulto Jovem
2.
Invest Ophthalmol Vis Sci ; 62(13): 24, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34698770

RESUMO

Purpose: Emmetropization requires coordinated scaling of the major ocular components, corneal curvature and axial length. This coordination is achieved in part through a shared set of genetic variants that regulate eye size. Poorly coordinated scaling of corneal curvature and axial length results in refractive error. We tested the hypothesis that genetic variants regulating eye size in emmetropic eyes are distinct from those conferring susceptibility to refractive error. Methods: A genome-wide association study (GWAS) for corneal curvature in 22,180 adult emmetropic individuals was performed as a proxy for a GWAS for eye size. A polygenic score created using lead GWAS variants was tested for association with corneal curvature and axial length in an independent sample: 437 classified as emmetropic and 637 as ametropic. The genetic correlation between eye size and refractive error was calculated using linkage disequilibrium score regression for approximately 1 million genetic variants. Results: The GWAS for corneal curvature in emmetropes identified 32 independent genetic variants (P < 5.0e-08). A polygenic score created using these 32 genetic markers explained 3.5% (P < 0.001) and 2.0% (P = 0.001) of the variance in corneal curvature and axial length, respectively, in the independent sample of emmetropic individuals but was not predictive of these traits in ametropic individuals. The genetic correlation between eye size and refractive error was close to zero (rg = 0.00; SE = 0.06; P = 0.95). Conclusions: These results support the hypothesis that genetic variants regulating eye size in emmetropic eyes do not overlap with those conferring susceptibility to myopia. This suggests that distinct biological pathways regulate normal eye growth and myopia development.


Assuntos
Comprimento Axial do Olho/diagnóstico por imagem , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Miopia/genética , Polimorfismo de Nucleotídeo Único , Refração Ocular/fisiologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Miopia/diagnóstico , Miopia/fisiopatologia , Adulto Jovem
3.
JAMA Ophthalmol ; 139(10): 1115-1121, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34529002

RESUMO

Importance: During the outbreak of COVID-19, outdoor activities were limited and digital learning increased. Concerns have arisen regarding the impact of these environmental changes on the development of myopia. Objective: To investigate changes in the development of myopia in young Chinese schoolchildren during the outbreak of COVID-19. Design, Setting, and Participants: In this observational study, 2 groups of students from 12 primary schools in Guangzhou, China, were prospectively enrolled and monitored from grade 2 to grade 3. Comparisons between the exposure and nonexposure groups were made to evaluate any association between environmental changes during the COVID-19 outbreak period and development of myopia. The exposure group received complete eye examinations in November and December 2019 and November and December 2020. The nonexposure group received examinations in November and December 2018 and November and December 2019. Main Outcomes and Measures: Changes in cycloplegic spherical equivalent refraction (SER), axial length (AL) elongation, and myopia incidence from grade 2 to grade 3. Results: Among the 2679 eligible students in grade 2 (mean [SD] age, 7.76 [0.32] years; 1422 [53.1%] male), 2114 (1060 in the nonexposure group and 1054 in the exposure group) were reexamined in grade 3. Compared with the period from November and December 2018 to November and December 2019, the shift of SER, AL elongation, and myopia incidence from grade 2 to grade 3 from November and December 2019 to November and December 2020 was 0.36 D greater (95% CI, 0.32-0.41; P < .001), 0.08 mm faster (95% CI, 0.06-0.10; P < .001), and 7.9% higher (95% CI, 5.1%-10.6%; P < .001), respectively. In grade 3 students, the prevalence of myopia increased from 13.3% (141 of 1060 students) in November and December 2019 to 20.8% (219 of 1054 students) in November and December 2020 (difference [95% CI], 7.5% [4.3-10.7]; P < .001); the proportion of children without myopia and with SER greater than -0.50 D and less than or equal to +0.50 D increased from 31.1% (286 of 919 students) to 49.0% (409 of 835 students) (difference [95% CI], 17.9% [13.3-22.4]; P < .001). Conclusions and Relevance: In this study, development of myopia increased during the COVID-19 outbreak period in young schoolchildren in China. Consequently, myopia prevalence and the proportion of children without myopia who were at risk of developing myopia increased. Future studies are needed to investigate long-term changes in myopia development after the COVID-19 pandemic.


Assuntos
COVID-19/prevenção & controle , Miopia/epidemiologia , Visão Ocular , Fatores Etários , COVID-19/epidemiologia , COVID-19/transmissão , Criança , China/epidemiologia , Humanos , Incidência , Miopia/diagnóstico , Miopia/fisiopatologia , Prevalência , Estudos Prospectivos , Recreação , Medição de Risco , Fatores de Risco , Tempo de Tela , Fatores de Tempo
4.
Invest Ophthalmol Vis Sci ; 62(12): 20, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34546324

RESUMO

Purpose: Wavelength and temporal frequency have been found to influence refractive development. This study investigated whether retinal dopamine (DA) plays a role in these processes. Methods: Guinea pigs were randomly divided into nine groups that received different lighting conditions for 4 weeks, as follows: white, green, or blue light at 0, 0.5, or 20.0 Hz. Refractions and axial lengths were measured using streak retinoscopy and A-scan ultrasound imaging. DA and its metabolites were measured by high-pressure liquid chromatography-electrochemical detection. Results: At 0 Hz, green and blue light produced myopic and hyperopic shifts compared with that of white light. At 0.5 Hz, no significant changes were observed compared with those of green or blue light at 0 Hz, whereas white light at 0.5 Hz induced a myopic shift compared with white light at 0 or 20 Hz. At 20 Hz, green and blue light acted like white light. Among all levels of DA and its metabolites, only vitreous 3, 4-dihydroxyphenylacetic acid (DOPAC) levels and retinal DOPAC/DA ratios were dependent on wavelength, frequency, and their interaction. Specifically, retinal DOPAC/DA ratios were positively correlated with refractions in white and green light conditions. However, blue light (0, 0.5, and 20.0 Hz) produced hyperopic shifts but decreased vitreous DOPAC levels and retinal DOPAC/DA ratios. Conclusions: The retinal DOPAC/DA ratio, indicating the metabolic efficiency of DA, is correlated with ocular growth. It may underlie myopic shifts from light exposure with a long wavelength and low temporal frequency. However, different biochemical pathways may contribute to the hyperopic shifts from short wavelength light.


Assuntos
Dopamina/fisiologia , Emetropia/fisiologia , Hiperopia/metabolismo , Miopia/metabolismo , Retina/efeitos da radiação , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Comprimento Axial do Olho/metabolismo , Cromatografia Líquida de Alta Pressão , Cobaias , Hiperopia/diagnóstico , Hiperopia/fisiopatologia , Luz , Miopia/diagnóstico , Miopia/fisiopatologia , Refração Ocular/fisiologia , Retina/metabolismo , Retinoscopia , Ultrassonografia , Corpo Vítreo/metabolismo
5.
Invest Ophthalmol Vis Sci ; 62(10): 11, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34379095

RESUMO

Purpose: To quantify astigmatism-related meridional anisotropy in visual resolution at central, nasal, and inferior visual fields. Methods: Three groups of young adults (range, 18-30 years) with corrected-to-normal visual acuity (logMAR 0) were recruited: (1) myopic astigmats (MA): spherical-equivalent error (SE) < -0.75D, with-the-rule astigmatism ≥ 2.00D, n = 19; (2) simple myopes (SM): SE < -0.75D, astigmatism ≤ 0.50D, n = 20; and (3) emmetropes (EM): SE ± 0.50D, astigmatism ≤ 0.50D, n = 14. Resolution acuity was measured for the horizontal and vertical gratings at central and peripheral visual fields (eccentricity: 15°) using a 3-down 1-up staircase paradigm. On- and off-axis refractive errors were corrected by ophthalmic lenses. Results: The MA group exhibited meridional anisotropy preferring vertical gratings. At the central field, the MA group had better resolution acuity for vertical than horizontal gratings, and their resolution acuity for horizontal gratings was significantly worse than the SM and EM groups. At peripheral visual fields, both the SM and EM groups showed better resolution acuity for the radial (i.e., nasal field: horizontal gratings; inferior field: vertical gratings) than tangential orientation. However, the MA group tended to have better resolution acuity for the tangential orientation (i.e., vertical gratings), and their resolution acuity for horizontal gratings was significantly lower than the SM and EM groups at the nasal field. No significant differences were found in the inferior field among the three groups. Conclusions: This study provided evidence of astigmatism-related meridional anisotropy at the fovea and nasal visual fields, underscoring the significant impact of astigmatism on orientation-dependent visual functions.


Assuntos
Astigmatismo/fisiopatologia , Emetropia/fisiologia , Fóvea Central/diagnóstico por imagem , Miopia/fisiopatologia , Refração Ocular/fisiologia , Acuidade Visual , Campos Visuais/fisiologia , Adolescente , Adulto , Anisotropia , Astigmatismo/diagnóstico , Feminino , Fóvea Central/fisiopatologia , Humanos , Masculino , Miopia/diagnóstico , Adulto Jovem
6.
Invest Ophthalmol Vis Sci ; 62(10): 16, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34406332

RESUMO

Purpose: To study the relatively high effect of the refractive error gene GJD2 in human myopia, and to assess its relationship with refractive error, ocular biometry and lifestyle in various age groups. Methods: The population-based Rotterdam Study (RS), high myopia case-control study MYopia STudy, and the birth-cohort study Generation R were included in this study. Spherical equivalent (SER), axial length (AL), axial length/corneal radius (AL/CR), vitreous depth (VD), and anterior chamber depth (ACD) were measured using standard ophthalmologic procedures. Biometric measurements were compared between GJD2 (rs524952) genotype groups; education and environmental risk score (ERS) were calculated to estimate gene-environment interaction effects, using the Synergy index (SI). Results: RS adults carrying two risk alleles had a lower SER and longer AL, ACD and VD (AA versus TT, 0.23D vs. 0.70D; 23.79 mm vs. 23.52 mm; 2.72 mm vs. 2.65 mm; 16.12 mm vs. 15.87 mm; all P < 0.001). Children carrying two risk alleles had larger AL/CR at ages 6 and 9 years (2.88 vs. 2.87 and 3.00 vs. 2.96; all P < 0.001). Education and ERS both negatively influenced myopia and the biometric outcomes, but gene-environment interactions did not reach statistical significance (SI 1.25 [95% confidence interval {CI}, 0.85-1.85] and 1.17 [95% CI, 0.55-2.50] in adults and children). Conclusions: The elongation of the eye caused by the GJD2 risk genotype follows a dose-response pattern already visible at the age of 6 years. These early effects are an example of how a common myopia gene may drive myopia.


Assuntos
Conexinas/genética , Regulação da Expressão Gênica , Miopia/genética , Vigilância da População , RNA/genética , Refração Ocular , Alelos , Câmara Anterior/diagnóstico por imagem , Comprimento Axial do Olho , Biometria , Estudos de Casos e Controles , Criança , Conexinas/biossíntese , Progressão da Doença , Feminino , Seguimentos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Miopia/diagnóstico , Miopia/fisiopatologia , Estudos Prospectivos
7.
Invest Ophthalmol Vis Sci ; 62(9): 11, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34236385

RESUMO

Purpose: To investigate the temporal characteristics of visual processing at the fovea and the periphery in high myopia. Methods: Eighteen low (LM, ≤ -0.50 and > -6.00 D) and 18 high myopic (HM, ≤ -6.00 D) participants took part in this study. The contrast thresholds in an orientation discrimination task under various stimulus onset asynchrony (SOA) masking conditions were measured at the fovea and a more peripheral area (7°) for the two groups. An elaborated perceptual template model (ePTM) was fit to the behavioral data for each participant. Results: An analysis of variance with three factors (SOA, degree of myopia and eccentricity) was performed on the threshold data. The interaction between SOA and degree of myopia in the fovea was significant (F (4, 128) = 2.66, P = 0.036), suggesting that the masking effect had different temporal patterns between the two groups. The temporal profiles for the two groups were derived based on the ePTM model. The peak and the spread of the temporal window in the fovea were much lower and wider, respectively, in the HM group than that in the LM group (both Ps < 0.05). There was no significant difference in the peripheral temporal window between the two groups. Conclusions: High myopia is associated with defective temporal processing in the fovea, captured by a flattened temporal window.


Assuntos
Fóvea Central/fisiopatologia , Miopia/fisiopatologia , Limiar Sensorial/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Fóvea Central/diagnóstico por imagem , Humanos , Masculino , Miopia/diagnóstico , Estimulação Luminosa
8.
Invest Ophthalmol Vis Sci ; 62(9): 16, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34241624

RESUMO

Purpose: The purpose of this study was to perform genetic linkage analysis and association analysis on exome genotyping from highly aggregated African American families with nonpathogenic myopia. African Americans are a particularly understudied population with respect to myopia. Methods: One hundred six African American families from the Philadelphia area with a family history of myopia were genotyped using an Illumina ExomePlus array and merged with previous microsatellite data. Myopia was initially measured in mean spherical equivalent (MSE) and converted to a binary phenotype where individuals were identified as affected, unaffected, or unknown. Parametric linkage analysis was performed on both individual variants (single-nucleotide polymorphisms [SNPs] and microsatellites) as well as gene-based markers. Family-based association analysis and transmission disequilibrium test (TDT) analysis modified for rare variants was also performed. Results: Genetic linkage analysis identified 2 genomewide significant variants at 7p15.2 and 7p14.2 (in the intergenic region between MIR148A and NFE2L3 and in the noncoding RNA LOC401324) and 2 genomewide significant genes (CRHR2 and AVL9) both at 7p14.3. No genomewide results were found in the association analyses. Conclusions: This study identified a significant linkage peak in African American families for myopia at 7p15.2 to 7p14.2, the first potential risk locus for myopia in African Americans. Interesting candidate genes are located in the region, including PDE1C, which is highly expressed in the eyes, and known to be involved in retinal development. Further identification of the causal variants at this linkage peak will help elucidate the genetics of myopia in this understudied population.


Assuntos
Afro-Americanos , Cromossomos Humanos Par 7/genética , Miopia/etnologia , Adulto , Mapeamento Cromossômico , Feminino , Ligação Genética , Predisposição Genética para Doença , Genoma Humano , Genótipo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Miopia/genética , Miopia/fisiopatologia , Linhagem , Philadelphia/epidemiologia , Refração Ocular
9.
Invest Ophthalmol Vis Sci ; 62(9): 21, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34259818

RESUMO

Purpose: The purpose of this study was to evaluate the role of the canonical Wnt signaling in the development of the myopia. Methods: Plasma from adult patients with myopia, myopic animal models including the adenomatous polyposis coli (APC) gene mutation mouse model, and the form deprivation (FD) induced mouse model of myopia were used. Niclosamide, a canonical Wnt pathway inhibitor, was orally administrated in animal models. Plasma levels of DKK-1 were determined by using enzyme-linked immunosorbent assay. Refraction, vitreous chamber depth (VCD), axial length (AL), and other parameters, were measured at the end of the FD treatment. Canonical Wnt signaling changes were evaluated by Western blot analysis and immunostaining analysis. Results: Plasma level of Wnt inhibitor DKK-1 was markedly decreased in patients with myopia. Meanwhile, the canonical Wnt pathway was progressively activated during myopia development in mice. Moreover, inhibition of canonical Wnt signaling by niclosamide in mouse models markedly reduced lens thickness (LT), VCD, and AL elongation, resulting in myopia inhibition. Conclusions: Dysregulation of canonical Wnt signaling is a characteristic of myopia and targeting Wnt signaling pathways has potential as a therapeutic strategy for myopia.


Assuntos
Segmento Anterior do Olho/metabolismo , Miopia/genética , Segmento Posterior do Olho/metabolismo , Refração Ocular/fisiologia , Via de Sinalização Wnt/genética , Adolescente , Adulto , Animais , Segmento Anterior do Olho/diagnóstico por imagem , Segmento Anterior do Olho/efeitos dos fármacos , Biomarcadores/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miopia/metabolismo , Miopia/fisiopatologia , Segmento Posterior do Olho/diagnóstico por imagem , Segmento Posterior do Olho/efeitos dos fármacos , Privação Sensorial , Adulto Jovem
10.
Invest Ophthalmol Vis Sci ; 62(9): 26, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279570

RESUMO

Purpose: To explore the associations between macular choroidal and retinal thickness and axial elongation in non-myopic and myopic junior students. Methods: In this school-based longitudinal observational study, axial length was measured by optical low-coherence reflectometry, and choroidal thickness and retinal thickness were measured by spectral-domain optical coherence tomography. Myopia was defined as non-cycloplegic objective spherical equivalent refraction ≤ -0.50 diopters. Structural equation modeling and multiple linear regression models were used to analyze the associations between baseline choroidal and retinal thickness with axial elongation. Results: Out of 1307 students examined at baseline in 2017, 1197 (91.58%) returned for follow-up examination in 2018, with a median age of 12.00 years (interquartile range [IQR], 1.00) and included 667 boys (55.72%). Within a 1-year period, the median axial elongation of right eyes was 230 µm (IQR, 180) in boys and 200 µm (IQR, 160) in girls (P = 0.032). The thinner temporal choroidal thickness was associated with greater 1-year axial elongation only in myopic students (ß, -0.20; 95% confidence interval [CI], -0.37, -0.03), the thinner temporal retinal thickness was associated with greater 1-year axial elongation in both non-myopic (ß, -2.67; 95% CI, -4.52, -0.82) and myopic (ß, -0.99; 95% CI, -1.68, -0.30) students, after adjustment for sex, age, and height. Subfoveal and nasal choroidal and retinal thickness were not significantly associated with axial elongation in either non-myopic or myopic students. Conclusions: A thinner temporal choroid at age 12 years may predict greater 1-year axial elongation in myopic students, and a thinner temporal retina may predict greater 1-year axial elongation in both non-myopic and myopic students. This finding may help to identify children at risk and control axial elongation with potential preventive strategies.


Assuntos
Comprimento Axial do Olho/patologia , Corioide/patologia , Miopia/diagnóstico , Refração Ocular/fisiologia , Retina/patologia , Estudantes , Tomografia de Coerência Óptica/métodos , Adolescente , Pequim/epidemiologia , Criança , Feminino , Humanos , Incidência , Masculino , Miopia/epidemiologia , Miopia/fisiopatologia , Testes Visuais , Acuidade Visual
11.
Invest Ophthalmol Vis Sci ; 62(9): 27, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34283211

RESUMO

Purpose: The purpose of this study was to determine whether retinal gap junctions (GJs) via connexin 36 (Cx36, mediating coupling of many retinal cell types) and horizontal cell (HC-HC) coupling, are involved in emmetropization. Methods: Guinea pigs (3 weeks old) were monocularly form deprived (FD) or raised without FD (in normal visual [NV] environment) for 2 days or 4 weeks; alternatively, they wore a -4 D lens (hyperopic defocus [HD]) or 0 D lens for 2 days or 1 week. FD and NV eyes received daily subconjunctival injections of a nonspecific GJ-uncoupling agent, 18-ß-Glycyrrhetinic Acid (18-ß-GA). The amounts of total Cx36 and of phosphorylated Cx36 (P-Cx36; activated state that increases cell-cell coupling), in the inner and outer plexiform layers (IPLs and OPLs), were evaluated by quantitative immunofluorescence (IF), and HC-HC coupling was evaluated by cut-loading with neurobiotin. Results: FD per se (excluding effect of light-attenuation) increased HC-HC coupling in OPL, whereas HD did not affect it. HD for 2 days or 1 week had no significant effect on retinal content of Cx36 or P-Cx36. FD for 4 weeks decreased the total amounts of Cx36 and P-Cx36, and the P-Cx36/Cx36 ratio, in the IPL. Subconjunctival 18-ß-GA induced myopia in NV eyes and increased the myopic shifts in FD eyes, while reducing the amounts of Cx36 and P-Cx36 in both the IPL and OPL. Conclusions: These results suggest that cell-cell coupling via GJs containing Cx36 (particularly those in the IPL) plays a role in emmetropization and form deprivation myopia (FDM) in mammals. Although both FD and 18-ß-GA induced myopia, they had opposite effects on HC-HC coupling. These findings suggest that HC-HC coupling in the OPL might not play a significant role in emmetropization and myopia development.


Assuntos
Conexinas/metabolismo , Emetropia/fisiologia , Junções Comunicantes/metabolismo , Hiperopia/metabolismo , Miopia/metabolismo , Retina/metabolismo , Corpo Vítreo/metabolismo , Animais , Túnica Conjuntiva/metabolismo , Túnica Conjuntiva/patologia , Modelos Animais de Doenças , Junções Comunicantes/patologia , Cobaias , Hiperopia/patologia , Hiperopia/fisiopatologia , Miopia/patologia , Miopia/fisiopatologia , Retina/patologia , Retina/fisiopatologia , Privação Sensorial , Corpo Vítreo/patologia
12.
Invest Ophthalmol Vis Sci ; 62(9): 40, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34319397

RESUMO

Purpose: The purpose of this study was to evaluate the interocular differences in choroidal vasculature, choriocapillaris perfusion, and retinal microvascular network, and to explore their associations with interocular asymmetry in axial lengths (ALs) in children with anisomyopia. Methods: Refractive error, AL, and other biometric parameters were measured in 70 children with anisomyopia. Using optical coherence tomography (OCT) and OCT-angiography, we measured the submacular choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), stromal area (SA), choroidal vascularity index (CVI), choriocapillaris flow deficit (CcFD), retinal vessel density (VD), and foveal avascular zone (FAZ) area. Results: The mean interocular differences in spherical equivalent refraction and AL were -2.26 ± 0.94 diopters and 0.95 ± 0.46 mm, respectively. Submacular ChT, TCA, LA, SA, and CVI were all significantly lower in the more myopic (longer AL) eyes than in the less myopic (shorter AL) fellow eyes. In eyes with longer ALs, both the CcFD and FAZ areas were significantly greater, whereas the superficial and deep retinal VDs were significantly less. After adjusting for corneal power and intraocular pressure, interocular differences in LA (ß = -0.774), SA (ß = -0.991), and CcFD (ß = 0.040) were significantly associated with interocular asymmetry in AL (all P < 0.05). Conclusions: In pediatric anisomyopes, eyes with longer ALs tended to have lower choroidal vascularity and choriocapillaris perfusion than the contralateral eyes with shorter ALs. Longitudinal investigations would be useful follow-ups to test for a causal role of choroidal circulation in human myopia.


Assuntos
Comprimento Axial do Olho/patologia , Corioide/irrigação sanguínea , Fóvea Central/irrigação sanguínea , Miopia/diagnóstico , Refração Ocular/fisiologia , Vasos Retinianos/patologia , Adolescente , Comprimento Axial do Olho/fisiopatologia , Biometria , Criança , Estudos Transversais , Feminino , Angiofluoresceinografia/métodos , Fundo de Olho , Humanos , Masculino , Microvasos , Miopia/fisiopatologia , Vasos Retinianos/metabolismo , Tomografia de Coerência Óptica/métodos
13.
J Am Heart Assoc ; 10(13): e020919, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34155898

RESUMO

Mitral valve prolapse (MVP) is a commonly occurring heart condition defined by enlargement and superior displacement of the mitral valve leaflet(s) during systole. Although commonly seen as a standalone disorder, MVP has also been described in case reports and small studies of patients with various genetic syndromes. In this review, we analyzed the prevalence of MVP within syndromes where an association to MVP has previously been reported. We further discussed the shared biological pathways that cause MVP in these syndromes, as well as how MVP in turn causes a diverse array of cardiac and noncardiac complications. We found 105 studies that identified patients with mitral valve anomalies within 18 different genetic, developmental, and connective tissue diseases. We show that some disorders previously believed to have an increased prevalence of MVP, including osteogenesis imperfecta, fragile X syndrome, Down syndrome, and Pseudoxanthoma elasticum, have few to no studies that use up-to-date diagnostic criteria for the disease and therefore may be overestimating the prevalence of MVP within the syndrome. Additionally, we highlight that in contrast to early studies describing MVP as a benign entity, the clinical course experienced by patients can be heterogeneous and may cause significant cardiovascular morbidity and mortality. Currently only surgical correction of MVP is curative, but it is reserved for severe cases in which irreversible complications of MVP may already be established; therefore, a review of clinical guidelines to allow for earlier surgical intervention may be warranted to lower cardiovascular risk in patients with MVP.


Assuntos
Síndrome de Ehlers-Danlos , Síndrome de Loeys-Dietz , Síndrome de Marfan , Prolapso da Valva Mitral , Miopia , Dermatopatias , Progressão da Doença , Síndrome de Ehlers-Danlos/diagnóstico , Síndrome de Ehlers-Danlos/epidemiologia , Síndrome de Ehlers-Danlos/fisiopatologia , Hemodinâmica , Humanos , Síndrome de Loeys-Dietz/diagnóstico , Síndrome de Loeys-Dietz/epidemiologia , Síndrome de Loeys-Dietz/fisiopatologia , Síndrome de Marfan/diagnóstico , Síndrome de Marfan/epidemiologia , Síndrome de Marfan/fisiopatologia , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/cirurgia , Prolapso da Valva Mitral/diagnóstico , Prolapso da Valva Mitral/epidemiologia , Prolapso da Valva Mitral/fisiopatologia , Prolapso da Valva Mitral/cirurgia , Miopia/diagnóstico , Miopia/epidemiologia , Miopia/fisiopatologia , Prevalência , Fatores de Risco , Dermatopatias/diagnóstico , Dermatopatias/epidemiologia , Dermatopatias/fisiopatologia , Resultado do Tratamento
14.
Ophthalmology ; 128(11): 1561-1579, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33961969

RESUMO

PURPOSE: The prevalence of myopia is increasing around the world, stimulating interest in methods to slow its progression. The primary justification for slowing myopia progression is to reduce the risk of vision loss through sight-threatening ocular pathologic features in later life. The article analyzes whether the potential benefits of slowing myopia progression by 1 diopter (D) justify the potential risks associated with treatments. METHODS: First, the known risks associated with various methods of myopia control are summarized, with emphasis on contact lens wear. Based on available data, the risk of visual impairment and predicted years of visual impairment are estimated for a range of incidence levels. Next, the increased risk of potentially sight-threatening conditions associated with different levels of myopia are reviewed. Finally, a model of the risk of visual impairment as a function of myopia level is developed, and the years of visual impairment associated with various levels of myopia and the years of visual impairment that could be prevented with achievable levels of myopia control are estimated. RESULTS: Assuming an incidence of microbial keratitis between 1 and 25 per 10 000 patient-years and that 15% of cases result in vision loss leads to the conclusion that between 38 and 945 patients need to be exposed to 5 years of wear to produce 5 years of vision loss. Each additional 1 D of myopia is associated with a 58%, 20%, 21%, and 30% increase in the risk of myopic maculopathy, open-angle glaucoma, posterior subcapsular cataract, and retinal detachment, respectively. The predicted mean years of visual impairment ranges from 4.42 in a person with myopia of -3 D to 9.56 in a person with myopia of -8 D, and a 1-D reduction would lower these by 0.74 and 1.21 years, respectively. CONCLUSIONS: The potential benefits of myopia control outweigh the risks: the number needed to treat to prevent 5 years of visual impairment is between 4.1 and 6.8, whereas fewer than 1 in 38 will experience a loss of vision as a result of myopia control.


Assuntos
Miopia/prevenção & controle , Refração Ocular/fisiologia , Medição de Risco/métodos , Progressão da Doença , Saúde Global , Humanos , Incidência , Miopia/epidemiologia , Miopia/fisiopatologia , Fatores de Risco
15.
Optom Vis Sci ; 98(5): 483-489, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33967252

RESUMO

SIGNIFICANCE: This pilot study compared subjective and objective vision of children wearing single-vision and +2.00, +3.00, and +4.00 D add power soft multifocal contact lenses to determine whether the higher add power-thought to provide better myopia control-resulted in visual compromise. PURPOSE: This study aimed to determine the maximum add power children wearing center-distance soft multifocal contact lenses could accept objectively and subjectively. METHODS: Myopic children were assigned in random order to wear omafilcon A single-vision or multifocal "D" contact lenses with +2.00, +3.00, or +4.00 D add power for 1 week each. High-contrast distance and near visual acuity, low-contrast distance visual acuity, and contrast sensitivity were measured at each visit along with a quality of vision questionnaire to assess their vision. The Friedman test was performed to evaluate the impact of add power on all outcome measures. RESULTS: Eleven subjects were enrolled, and nine subjects completed the study. The median age of completed subjects was 11 years. Median logMAR low-contrast distance visual acuity was reduced in the +3.00 (+0.20) and +4.00 (+0.28) D add lenses compared with the +2.00 (+0.16) D add and single-vision lenses (+0.10, P < .001). All three multifocal lenses resulted in reduced contrast sensitivity (+1.35 to +1.40) compared with single-vision lenses (+1.60, P < .001). In general, +3.00 and +4.00 D add lenses resulted in worse glare/starbursts, ghost images, computer vision, changing fixation distance, and overall vision, but results varied. There were no differences among the lenses with respect to subjective assessments of distance vision, near vision, strain or tiredness, contact lens comfort, or sporting activities. CONCLUSIONS: The +3.00 D and higher add powers result in more objective and subjective vision-related issues than single-vision lenses, but the +2.00 D add multifocal lenses were well tolerated.


Assuntos
Lentes de Contato Hidrofílicas , Sensibilidades de Contraste/fisiologia , Miopia/terapia , Acuidade Visual/fisiologia , Criança , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Projetos Piloto , Inquéritos e Questionários
16.
Optom Vis Sci ; 98(5): 476-482, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33973919

RESUMO

SIGNIFICANCE: This research found that anterior and posterior biometrics differ in many aspects between fellow eyes of anisometropic children. This might shed light on the mechanisms underlying the onset and progression of anisometropia and myopia. PURPOSE: This study aimed to investigate the ocular biometric parameters, peripheral refraction, and accommodative lag of fellow eyes in anisometropic children. METHODS: Anisometropic children were recruited. Axial length (AL), vitreous chamber depth (VCD), central corneal thickness, anterior chamber depth (ACD), lens thickness (LT), simulated K readings, central and peripheral refractive errors, and accommodative lag were measured in both eyes. The subfoveal choroidal thickness, average choroidal thickness, and choroid vessel density of the 6 × 6-mm macular area were measured by optical coherence tomography. RESULTS: Thirty-two children aged 11.1 ± 1.7 years were enrolled. The average degree of anisometropia was 2.49 ± 0.88 D. The AL, VCD, ACD, and simulated K reading values were significantly larger in the more myopic eyes, whereas the LT value was significantly smaller. Subfoveal choroidal thickness (P = .001) and average choroidal thickness (P = .02) were smaller in the more myopic eyes than in the contralateral eyes, whereas choroid vessel density (P = .03) was larger. The amount of anisometropia had a significant positive correlation with the difference in AL (r = 0.869, P < .001), VCD (r = 0.853, P < .001), and ACD (r = 0.591, P < .001) and a negative correlation with the difference in LT (r = -0.457, P = .009). CONCLUSIONS: Ocular biometrics differ in many aspects between the fellow eyes of anisometropic Chinese children, and the difference is correlated with the degree of anisometropia.


Assuntos
Acomodação Ocular/fisiologia , Anisometropia/fisiopatologia , Refração Ocular/fisiologia , Adolescente , Segmento Anterior do Olho/patologia , Comprimento Axial do Olho/patologia , Biometria , Criança , Corioide/patologia , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Erros de Refração/fisiopatologia , Tomografia de Coerência Óptica/métodos
17.
Invest Ophthalmol Vis Sci ; 62(4): 31, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33929483

RESUMO

Purpose: The purpose of this study was to characterize age-related changes in anterior human vitreous with 3-D swept source optical coherence tomography (SS-OCT) and evaluate associations with axial length (AL) and contrast sensitivity function (CSF). Methods: There were 49 phakic eyes in 49 patients (40.0 ± 19.3 years) had 3-D volumetric scanning of the lens and retrolental vitreous with SS-OCT at 1050 nm. OCT-derived indices of vitreous optical density (VOD), vitreous opacification ratio (VOR), and lens optical density (LOD) were correlated with AL and double-pass assessment of retinal point spread function (Objective Scatter Index [OSI]). CSF was measured using an adaptive-optics visual simulator (area under log-log contrast sensitivity function [AULCSF]). Results: Vitreous SS-OCT detected gel vitreous, liquefied lacunae, Berger's space, retrolental laminae, and fibrous opacifications. VOD, VOR, and LOD showed high reproducibility (intraclass correlation coefficients 0.968, 0.975, and 0.998, respectively). VOD was highly correlated with VOR (Pearson's R = 0.96, P < 0.000001). VOD, VOR, and LOD correlated with age (R = 0.48, 0.58, and 0.85, P < 0.001 for each). VOR and LOD correlated with OSI (R = 0.36, P = 0.0094, and R = 0.36, P = 0.0096, respectively). VOR correlated negatively with AULCSF (R = -0.53, P < 0.00009), which was related to OSI. Myopic eyes had higher OSI than nonmyopic eyes (P = 0.0121), consistent with correlation between OSI and AL (R = 0.37, P = 0.0091). Multivariable regression confirmed these findings. Conclusions: SS-OCT visualized microstructural features of anterior human vitreous, where opacification is associated with increased light scattering and CSF degradation. SS-OCT enables high-resolution optical evaluation of vitreous opacities.


Assuntos
Envelhecimento , Comprimento Axial do Olho/diagnóstico por imagem , Sensibilidades de Contraste/fisiologia , Miopia/diagnóstico , Tomografia de Coerência Óptica/métodos , Corpo Vítreo/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Estudos Transversais , Feminino , Humanos , Cristalino/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Miopia/fisiopatologia , Reprodutibilidade dos Testes , Adulto Jovem
18.
Invest Ophthalmol Vis Sci ; 62(5): 7, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909031

RESUMO

Purpose: The International Myopia Institute (IMI) Yearly Digest highlights new research considered to be of importance since the publication of the first series of IMI white papers. Methods: A literature search was conducted for articles on myopia between 2019 and mid-2020 to inform definitions and classifications, experimental models, genetics, interventions, clinical trials, and clinical management. Conference abstracts from key meetings in the same period were also considered. Results: One thousand articles on myopia have been published between 2019 and mid-2020. Key advances include the use of the definition of premyopia in studies currently under way to test interventions in myopia, new definitions in the field of pathologic myopia, the role of new pharmacologic treatments in experimental models such as intraocular pressure-lowering latanoprost, a large meta-analysis of refractive error identifying 336 new genetic loci, new clinical interventions such as the defocus incorporated multisegment spectacles and combination therapy with low-dose atropine and orthokeratology (OK), normative standards in refractive error, the ethical dilemma of a placebo control group when myopia control treatments are established, reporting the physical metric of myopia reduction versus a percentage reduction, comparison of the risk of pediatric OK wear with risk of vision impairment in myopia, the justification of preventing myopic and axial length increase versus quality of life, and future vision loss. Conclusions: Large amounts of research in myopia have been published since the IMI 2019 white papers were released. The yearly digest serves to highlight the latest research and advances in myopia.


Assuntos
Miopia/terapia , Procedimentos Ortoceratológicos/métodos , Qualidade de Vida , Refração Ocular/fisiologia , Progressão da Doença , Humanos , Miopia/classificação , Miopia/fisiopatologia
19.
Invest Ophthalmol Vis Sci ; 62(5): 6, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909032

RESUMO

The prevalence of myopia has markedly increased in East and Southeast Asia, and pathologic consequences of myopia, including myopic maculopathy and high myopia-associated optic neuropathy, are now some of the most common causes of irreversible blindness. Hence, strategies are warranted to reduce the prevalence of myopia and the progression to high myopia because this is the main modifiable risk factor for pathologic myopia. On the basis of published population-based and interventional studies, an important strategy to reduce the development of myopia is encouraging schoolchildren to spend more time outdoors. As compared with other measures, spending more time outdoors is the safest strategy and aligns with other existing health initiatives, such as obesity prevention, by promoting a healthier lifestyle for children and adolescents. Useful clinical measures to reduce or slow the progression of myopia include the daily application of low-dose atropine eye drops, in concentrations ranging between 0.01% and 0.05%, despite the side effects of a slightly reduced amplitude of accommodation, slight mydriasis, and risk of an allergic reaction; multifocal spectacle design; contact lenses that have power profiles that produce peripheral myopic defocus; and orthokeratology using corneal gas-permeable contact lenses that are designed to flatten the central cornea, leading to midperipheral steeping and peripheral myopic defocus, during overnight wear to eliminate daytime myopia. The risk-to-benefit ratio needs to be weighed up for the individual on the basis of their age, health, and lifestyle. The measures listed above are not mutually exclusive and are beginning to be examined in combination.


Assuntos
Acomodação Ocular/fisiologia , Lentes de Contato , Óculos , Miopia/prevenção & controle , Refração Ocular/fisiologia , Progressão da Doença , Saúde Global , Humanos , Miopia/epidemiologia , Miopia/fisiopatologia , Prevalência
20.
Invest Ophthalmol Vis Sci ; 62(5): 4, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909034

RESUMO

The role of accommodation in myopia development and progression has been debated for decades. More recently, the understanding of the mechanisms involved in accommodation and the consequent alterations in ocular parameters has expanded. This International Myopia Institute white paper reviews the variations in ocular parameters that occur with accommodation and the mechanisms involved in accommodation and myopia development and progression. Convergence is synergistically linked with accommodation and the impact of this on myopia has also been critiqued. Specific topics reviewed included accommodation and myopia, role of spatial frequency, and contrast of the task of objects in the near environment, color cues to accommodation, lag of accommodation, accommodative-convergence ratio, and near phoria status. Aspects of retinal blur from the lag of accommodation, the impact of spatial frequency at near and a short working distance may all be implicated in myopia development and progression. The response of the ciliary body and its links with changes in the choroid remain to be explored. Further research is critical to understanding the factors underlying accommodative and binocular mechanisms for myopia development and its progression and to guide recommendations for targeted interventions to slow myopia progression.


Assuntos
Acomodação Ocular/fisiologia , Convergência Ocular/fisiologia , Miopia/fisiopatologia , Visão Binocular/fisiologia , Progressão da Doença , Humanos , Refração Ocular/fisiologia
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