ABSTRACT
OBJECTIVE: To evaluate the relationship between nuclear sclerosis (NS) and refractive error in companion dogs. ANIMALS STUDIED: One hundred and eighteen companion dogs. PROCEDURES: Dogs were examined and found to be free of significant ocular abnormalities aside from NS. NS was graded from 0 (absent) to 3 (severe) using a scale developed by the investigators. Manual refraction was performed. The effect of NS grade on refractive error was measured using a linear mixed effects analysis adjusted for age. The proportion of eyes with >1.5 D myopia in each NS grade was evaluated using a chi-square test. Visual impairment score (VIS) was obtained for a subset of dogs and compared against age, refractive error, and NS grade. RESULTS: Age was strongly correlated with NS grade (p < .0001). Age-adjusted analysis of NS grade relative to refraction showed a mild but not statistically significant increase in myopia with increasing NS grade, with eyes with grade 3 NS averaging 0.58-0.88 D greater myopia than eyes without NS. However, the myopia of >1.5 D was documented in 4/58 (6.9%) eyes with grade 0 NS, 12/91 (13.2%) eyes with grade 1 NS, 13/57 (22.8%) eyes with grade 2 NS, and 7/23 (30.4%) eyes with grade 3 NS. Risk of myopia >1.5 D was significantly associated with increasing NS grade (p = .02). VIS was associated weakly with refractive error, moderately with age, and significantly with NS grade. CONCLUSIONS: NS is associated with visual deficits in some dogs but is only weakly associated with myopia. More work is needed to characterize vision in aging dogs.
Subject(s)
Cataract , Dog Diseases , Myopia , Refractive Errors , Dogs , Animals , Pets , Sclerosis/pathology , Sclerosis/veterinary , Eye/pathology , Refractive Errors/veterinary , Refractive Errors/pathology , Refraction, Ocular , Myopia/pathology , Myopia/veterinary , Dog Diseases/pathologyABSTRACT
PURPOSE: To investigate the differences in the dimensions of the anterior ocular segment, and specifically in conjunctival-Tenon's capsule thickness (CTT), anterior scleral thickness (AST) and ciliary muscle thickness (CMT), between Caucasian and Hispanic subjects using swept-source optical coherence tomography (SS-OCT). METHODS: Cross-sectional study including 53 Hispanic and 60 Caucasian healthy participants, matched by age, sex and refractive error, who underwent a complete ophthalmological examination. CTT, AST and CMT were manually measured in the temporal and nasal quadrants at 0, 1, 2 and 3 mm from the scleral spur using SS-OCT. RESULTS: Mean age and refractive error were 38.7 ± 12.3 years and -1.05 ± 2.6 diopters, and 41.8 ± 11.7 years and -0.50 ± 2.6 diopters for the Hispanic and Caucasians, respectively (p = 0.165 and p = 0.244). The CTT was increased in the temporal quadrant in the Hispanic group in the three studied regions (CTT1, CTT2 and CTT3; being the means 223.0 ± 68.4, 215.3 ± 66.4 and 203.8 ± 67.1 µm versus 190.8 ± 51.0, 189.4 ± 53.2 and 187.4 ± 55.3 µm respectively; p < 0.001). Larger AST values were observed in the temporal quadrant in the Hispanic group (AST2: 559.8 ± 80.8 µm and AST3: 591.6 ± 83.0 µm) compared to the Caucasian group (520.7 ± 50.1 and 558.9 ± 54.7 respectively; p ≤ 0.022). No differences were observed in the nasal quadrant for CTT, AST1 and AST3 (p ≥ 0.076). No differences emerged in the CM dimensions (p ≥ 0.055). CONCLUSION: CTT and AST measurements were thicker in the temporal quadrant of Hispanic patients compared to Caucasians. This could have implications for the pathogenesis of different ocular diseases.
Subject(s)
Refractive Errors , Sclera , Humans , Cross-Sectional Studies , Hispanic or Latino , Muscles , Refractive Errors/pathology , Tenon Capsule , Tomography, Optical Coherence/methods , White , Adult , Middle AgedABSTRACT
Los errores de refracción contribuyen como un gran problema de salud pública. Las crecientes tasas de prevalencia de la miopía han alcanzado los niveles de epidemia en varias áreas. Este estudio tuvo como objetivo determinar las tasas de prevalencia de errores de refracción en los estudiantes de medicina. Se realizó un estudio prospectivo en el Departamento de Oftalmología, durante un período de un año desde enero de 2020 hasta diciembre de 2020. Los estudiantes de medicina fueron seleccionados al azar, como un total de 250 sujetos. Todos se sometieron a un examen oftálmico. De 250 estudiantes, se documentaron 148 (59.2%) casos de RE. La mayoría de los casos comunes eran mujeres (89, 60.1%), mientras que los hombres eran (59, 39.9%). De estos, 98 estudiantes tienen miopía (66.2%), 42 casos tienen astigmatismo (28.4%) y 8 casos tienen hipermetropía (5.4%). La etapa tardía de las clases (sexto) tiene los casos RE más frecuentes. La miopía fue la RE predominante entre los estudiantes de medicina. La clase anticipada y la mujer son factores predisponentes.
Refractive errors are contributing as a major public health problem. The increasing prevalence rates of myopia have reaching to epidemic levels in several areas. This study was aimed to determine the prevalence rates of refractive errors in medical students. A prospective study was conducted in the Department of Ophthalmology, over a period of one year from Jan 2020 to Dec 2020. Medical students were randomly selected, as a total of 250 subjects. All were undergoing an ophthalmic examination. Of 250 students, 148(59.2%) cases of RE were documented. Most common cases were female (89, 60.1%), whereas male was (59, 39.9%). Of these, 98 students have myopia (66.2%), 42 cases have astigmatism (28.4%) and 8 cases have hypermetropia (5.4%). The late stage of classes (6th) has the most frequent RE cases. Myopia was the predominant RE among the medical students. Advance class and female are predisposing factors
Subject(s)
Humans , Adult , Refractive Errors/pathology , Astigmatism/diagnosis , Students, Medical , Prevalence , Myopia/diagnosisABSTRACT
Determinar la prevalencia del error de refracción (RE) como causa en los ojos en los niños en niños de esta edad (6-12 años) en la ciudad de Sulaimania. El estudio de tasa de prevalencia entre los pacientes que asisten al Shahed Dr. Aso Eye Hospital para el período del 1 de octubre de 2008 al 1 de junio de 2009. Un total de 116 niños (6-12 años) asisten al departamento de entrecerrares durante aproximadamente 8 meses. El estudio incluyó ambos sexos, eran niños de 55 años y niñas 61. Se sometieron a un examen ocular completo. Encontramos que (72) pacientes (62.02 %) tenían un error de refracción, incluyen: 33 pacientes (45.9 %) = hipermetropia (H); 22 pacientes (29.16%) = miopía [m]; 18 pacientes (24.3%) astigmatismo (AST.); 4 mixtos; 6 h-as. y 8 m-as. En conclusiones, la causa más frecuente del entrecerrar de la infancia a este ancho [6-12 años) es el error refractivo, mientras que las otras causas en su conjunto constituyen solo 1/3 de las causas, y el error de refracción más común es la hipermetropía
To determine the prevalence of refractive error (RE) as a cause in squinted in children in this aged (6-12 years) in Sulaimania city. The prevalence rate study among patient attending Shahed Dr. Aso eye hospital for the period from 1st October 2008 - 1st June 2009. A total of 116 children ( 6-12 years) attending squint department for about 8 months. The study included both sexes, were boys 55 and girls 61. Underwent full ocular examination. We found that (72) patients (62.02%) had refractive error, include: 33 patients (45.9 %) = Hypermetropia (H); 22 patients (29.16%) = Myopia [M]; 18 patients (24.3%) Astigmatism (Ast.); 4 mixed; 6 H-Ast. and 8 M-Ast. In conclusions, the most prevalent cause of childhood squint at this aged [6-12 years) is refractive error while the other causes as a whole constitute only 1/3 of the causes, and most common refractive error is hypermetropia
Subject(s)
Humans , Male , Female , Child , Refractive Errors/pathology , Astigmatism/pathology , Hyperopia/pathology , Myopia/pathologyABSTRACT
Purpose: To identify the association between the choroidal thickness (ChT) with age and axial length (AL) under different refractive errors (REs) in Chinese adults. Methods: Swept-source optical coherence tomography was used to measure ChT in 2126 right eyes of 2126 participants. The participants were classified as having pathologic myopia (PM), high myopia without PM (HM), low myopia (LM), and nonmyopia (non-M) according to their REs and META-PM (the Meta-Analysis of Pathologic Myopia) classification criteria. Results: The mean age was 52.49 ± 20.39 years (range, 18-93 years), and the mean RE was -5.27 ± 5.37 diopters (D; range, -25.5 to +7.75 D). The mean average ChT was 159.25 ± 80.75 µm and decreased in a linear relationship from non-M to PM (190.04 ± 72.64 µm to 60.99 ± 37.58 µm, P < 0.001). A significant decline in ChT was noted between 50 and 70 years (r = -0.302, P < 0.001) and less rapidly after the age of 70 years (r = -0.105, P = 0.024). No correlation was noted between age and ChT under 50 years (P = 0.260). A significantly higher association with AL was noted in the central fovea (ßHM = -23.92, ßLM = -23.88, ßNon-M = -18.80, all P < 0.001) and parafoveal ChT (ßHM = -22.87, ßLM = -22.31, ßNon-M = -18.61, all P < 0.001) when compared with the perifoveal region (ßHM = -19.80, ßLM = -18.29, ßNon-M = -13.95, all P < 0.001). Within each group of PM, HM, LM, and non-M, regression analysis showed that the coefficients of age and AL with different macular regions of ChT varied significantly. Conclusions: ChT was negatively correlated with age after 50 years. The thinning of the choroid was more prominent in the center and parafoveal regions as AL increased. Varied distributions of ChT decrease associated with AL and age were noted among different refractive groups.
Subject(s)
Myopia , Refractive Errors , Adult , Aged , China/epidemiology , Choroid/pathology , Humans , Middle Aged , Myopia/diagnosis , Myopia/pathology , Refractive Errors/epidemiology , Refractive Errors/pathology , Tomography, Optical Coherence/methodsABSTRACT
Myopia tends to develop and progress fastest during childhood, and the age of stabilization has been reported to be 15-16 years old. Thus, most studies on myopia have centered on children. Data on the refractive error profile in young adulthood - a time in life when myopia is thought to have stabilized and refractive error is unaffected by age-related pathology such as cataract - are limited. The Raine Study has been following a community-based cohort of young adults representative of the general Western Australia population since their prenatal periods in 1989-1991, with eye examinations performed when participants were 20 and 28 years old. At 20 years old, prevalence of myopia in the cohort was 25.8%. Using long-term trajectory of serum vitamin D levels and conjunctival ultraviolet autofluorescence (CUVAF) area to objectively quantify sun exposure, the Raine Study confirmed a negative relationship between time spent outdoors and myopia prevalence. However, prospective studies are required to determine the amount of CUVAF area or serum vitamin D levels associated with time duration. Combining data from the Raine Study and several other cohorts, Mendelian randomization studies have confirmed a link between myopia and a genetic predisposition toward higher education. Several novel potential associations of myopia or ocular biometry were investigated, including fetal growth trajectory, which was found to be significantly associated with corneal curvature at 20 years. By age 28, myopia prevalence had increased to 33.2%. Between 20 and 28 years old, myopia progressed and axial length elongated, on average, by -0.041D/year and 0.02 mm/year, respectively. Smaller CUVAF area at follow-up, female sex, and parental myopia were significant risk factors for myopia incidence and progression between 20 and 28 years. Given the limited research in young adults, further investigations are warranted to confirm the Raine Study findings, as well as identify novel genetic or environmental factors of myopia incidence and progression in this age group.
Subject(s)
Myopia , Refractive Errors , Adolescent , Adult , Child , Conjunctiva , Female , Humans , Myopia/epidemiology , Myopia/etiology , Pregnancy , Prevalence , Refractive Errors/complications , Refractive Errors/pathology , Risk Factors , Vitamin D , Young AdultABSTRACT
PURPOSE: To examine whether data sourced from electronic medical records (EMR) and a large industrial spectacle lens manufacturing database can estimate refractive error distribution within large populations as an alternative to typical population surveys of refractive error. SUBJECTS: A total of 555,528 patient visits from 28 Irish primary care optometry practices between the years 1980 and 2019 and 141,547,436 spectacle lens sales records from an international European lens manufacturer between the years 1998 and 2016. METHODS: Anonymized EMR data included demographic, refractive and visual acuity values. Anonymized spectacle lens data included refractive data. Spectacle lens data was separated into lenses containing an addition (ADD) and those without an addition (SV). The proportions of refractive errors from the EMR data and ADD lenses were compared to published results from the European Eye Epidemiology (E3) Consortium and the Gutenberg Health Study (GHS). RESULTS: Age and gender matched proportions of refractive error were comparable in the E3 data and the EMR data, with no significant difference in the overall refractive error distribution (χ2 = 527, p = 0.29, DoF = 510). EMR data provided a closer match to the E3 refractive error distribution by age than the ADD lens data. The ADD lens data, however, provided a closer approximation to the E3 data for total myopia prevalence than the GHS data, up to age 64. CONCLUSIONS: The prevalence of refractive error within a population can be estimated using EMR data in the absence of population surveys. Industry derived sales data can also provide insights on the epidemiology of refractive errors in a population over certain age ranges. EMR and industrial data may therefore provide a fast and cost-effective surrogate measure of refractive error distribution that can be used for future health service planning purposes.
Subject(s)
Big Data , Myopia/epidemiology , Refractive Errors/epidemiology , Visual Acuity/physiology , Adult , Age Distribution , Aged , Contact Lenses , Data Management , Electronic Health Records , Epidemiologic Studies , Eyeglasses , Female , Humans , Ireland/epidemiology , Male , Middle Aged , Myopia/diagnosis , Myopia/pathology , Myopia/prevention & control , Refractive Errors/pathology , Refractive Errors/prevention & control , Sex Distribution , Vision Tests , Young AdultABSTRACT
Ametropia is one of the most common ocular disorders worldwide, to which almost half of visual impairments are attributed. Growing evidence has linked the development of ametropia with ambient light, including blue light, which is ubiquitous in our surroundings and has the highest photonic energy among the visible spectrum. However, the underlying mechanism of blue light-mediated ametropia remains controversial and unclear. In the present study, our data demonstrated that exposure of the retinal pigment epithelium (RPE) to blue light elevated the levels of the vital ametropia-related factor type â collagen (COL1) via ß-catenin inhibition in scleral fibroblasts, leading to axial ametropia (hyperopic shift). Herein, our study provides evidence for the vital role of blue light-induced RPE dysfunction in the process of blue light-mediated ametropia, providing intriguing insights into ametropic aetiology and pathology by proposing a link among blue light, RPE dysfunction and ametropia.
Subject(s)
Light , Refractive Errors/pathology , Retinal Pigment Epithelium/pathology , Retinal Pigment Epithelium/radiation effects , Animals , Cell Line , Cell Survival/radiation effects , Collagen Type I/metabolism , Fibroblasts/pathology , Fibroblasts/radiation effects , Gene Expression Regulation/radiation effects , Humans , Male , Mice, Inbred C57BL , Refractive Errors/genetics , Refractometry , Sclera/pathology , Up-Regulation/radiation effects , beta Catenin/metabolismABSTRACT
Dual-specificity tyrosine phosphorylation-regulated kinase 1A or DYRK1A, contributes to central nervous system development in a dose-sensitive manner. Triallelic DYRK1A is implicated in the neuropathology of Down syndrome, whereas haploinsufficiency causes the rare DYRK1A-related intellectual disability syndrome (also known as mental retardation 7). It is characterised by intellectual disability, autism spectrum disorder and microcephaly with a typical facial gestalt. Preclinical studies elucidate a role for DYRK1A in eye development and case studies have reported associated ocular pathology. In this study families of the DYRK1A Syndrome International Association were asked to self-report any co-existing ocular abnormalities. Twenty-six patients responded but only 14 had molecular confirmation of a DYRK1A pathogenic variant. A further nineteen patients from the UK Genomics England 100,000 Genomes Project were identified and combined with 112 patients reported in the literature for further analysis. Ninety out of 145 patients (62.1%) with heterozygous DYRK1A variants revealed ocular features, these ranged from optic nerve hypoplasia (13%, 12/90), refractive error (35.6%, 32/90) and strabismus (21.1%, 19/90). Patients with DYRK1A variants should be referred to ophthalmology as part of their management care pathway to prevent amblyopia in children and reduce visual comorbidity, which may further impact on learning, behaviour, and quality of life.
Subject(s)
Central Nervous System/abnormalities , Central Nervous System/pathology , Intellectual Disability/genetics , Optic Nerve Diseases/genetics , Optic Nerve/abnormalities , Protein Serine-Threonine Kinases/genetics , Protein-Tyrosine Kinases/genetics , Central Nervous System/growth & development , Central Nervous System/metabolism , Child , Child, Preschool , Down Syndrome/genetics , Down Syndrome/pathology , Eye/pathology , Eye Abnormalities/genetics , Eye Abnormalities/pathology , Female , Haploinsufficiency/genetics , Humans , Infant , Intellectual Disability/pathology , Male , Middle Aged , Optic Nerve/pathology , Optic Nerve Diseases/pathology , Refractive Errors/genetics , Refractive Errors/pathology , Strabismus/genetics , Strabismus/pathology , Dyrk KinasesABSTRACT
Purpose: To evaluate the focal structure-function associations among visual field (VF) loss, optical coherence tomography angiography (OCT-A) vascular measurements, and optical coherence tomography (OCT) structural measurements in glaucoma. Methods: In this cross-sectional study, subjects underwent standard automated perimetry, OCT-based nerve fiber thickness measurements, and OCT-A imaging. Mappings of focal VF test locations with OCT and OCT-A measurements were defined using anatomically adjusted nerve fiber trajectories and were studied using multivariate mixed-effects analysis. Segmented regression analysis was used to determine the presence of breakpoints in the structure-function associations. Results: The study included 119 eyes from 86 Chinese subjects with primary open-angle glaucoma (POAG). VF mean deviation was significantly associated with global capillary perfusion density (ß = 0.13 ± 0.08) and global retinal nerve fiber layer thickness (ß = 0.09 ± 0.02). Focal capillary density (FCD) was significantly associated with VF losses at 34 VF test locations (66.7% of 24-2 VF), with 24 of the 34 locations being within 20° of retinal eccentricity. Focal nerve layer (FNL) thickness was significantly associated with 16 VF test locations (31.4% of 24-2 VF; eight locations within 20° eccentricity). For VF test locations in the central 10° VF, VF losses below the breakpoint were significantly associated with FCD (slope, 0.89 ± 0.12, P < 0.001), but not with FNL thickness (slope, 0.57 ± 0.39, P = 0.15). Conclusions: Focal capillary densities were significantly associated with a wider range of visual field losses and in a larger proportion of the visual field compared to nerve fiber thickness.
Subject(s)
Glaucoma, Open-Angle/diagnostic imaging , Aged , Female , Fovea Centralis/diagnostic imaging , Fovea Centralis/pathology , Glaucoma, Open-Angle/pathology , Humans , Intraocular Pressure , Male , Refractive Errors/diagnostic imaging , Refractive Errors/pathology , Retina/diagnostic imaging , Retina/pathology , Tomography, Optical Coherence , Visual FieldsABSTRACT
This study aimed to determine whether inter-ocular differences in axial length (AL), corneal power (K), and adjusted emmetropic intraocular lens power (EIOLP) and inter-visit differences in these ocular biometric values, measured on different days, are related to refractive outcomes after cataract surgery. We retrospectively reviewed 279 patients who underwent phacoemulsification. Patients underwent ocular biometry twice (1-4 weeks before and on the day of surgery). Patients were divided into three groups: group S (similar inter-ocular biometry in different measurements; n = 201), group P (inter-ocular differences persisted in the second measurement; n = 37), and group D (inter-ocular difference diminished in the second measurement; n = 41). Postoperative refractive outcomes (mean absolute errors [MAEs]) were compared among the groups. Postoperative MAE2, based on second measurement with reduced inter-ocular biometry difference, was smaller than that calculated using the first measurement (MAE1) with borderline significance in group D (MAE1, 0.49 ± 0.45 diopters vs. MAE2, 0.41 ± 0.33 diopters, p = 0.062). Postoperative MAE2 was greater in group P compared to the other two groups (p = 0.034). Large inter-ocular biometry differences were associated with poor refractive outcomes after cataract surgery. These results indicate that measurements with smaller inter-ocular differences were associated with better refractive outcomes in cases with inter-visit biometry differences.
Subject(s)
Cataract Extraction , Cataract/pathology , Refractive Errors/pathology , Aged , Aged, 80 and over , Biometry , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment OutcomeABSTRACT
Genome-wide association studies (GWAS) have revealed that the genetic contribution to certain complex diseases is well-described by Fisher's infinitesimal model in which a vast number of polymorphisms each confer a small effect. Under Fisher's model, variants have additive effects both across loci and within loci. However, the latter assumption is at odds with the common observation of dominant or recessive rare alleles responsible for monogenic disorders. Here, we searched for evidence of non-additive (dominant or recessive) effects for GWAS variants known to confer susceptibility to the highly heritable quantitative trait, refractive error. Of 146 GWAS variants examined in a discovery sample of 228,423 individuals whose refractive error phenotype was inferred from their age-of-onset of spectacle wear, only 8 had even nominal evidence (p < 0.05) of non-additive effects. In a replication sample of 73,577 individuals who underwent direct assessment of refractive error, 1 of these 8 variants had robust independent evidence of non-additive effects (rs7829127 within ZMAT4, p = 4.76E-05) while a further 2 had suggestive evidence (rs35337422 in RD3L, p = 7.21E-03 and rs12193446 in LAMA2, p = 2.57E-02). Accounting for non-additive effects had minimal impact on the accuracy of a polygenic risk score for refractive error (R2 = 6.04% vs. 6.01%). Our findings demonstrate that very few GWAS variants for refractive error show evidence of a departure from an additive mode of action and that accounting for non-additive risk variants offers little scope to improve the accuracy of polygenic risk scores for myopia.
Subject(s)
Genome-Wide Association Study , Myopia/genetics , Quantitative Trait, Heritable , Refractive Errors/genetics , Adult , Aged , Biological Specimen Banks , Female , Genes, Dominant/genetics , Genetic Predisposition to Disease , Genetic Variation/genetics , Humans , Laminin/genetics , Male , Middle Aged , Multifactorial Inheritance/genetics , Myopia/pathology , Polymorphism, Single Nucleotide/genetics , Refractive Errors/pathologySubject(s)
ATP-Binding Cassette Transporters/genetics , Mutation , Refractive Errors/pathology , Retinal Diseases/complications , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Prognosis , Refractive Errors/etiology , Retinal Diseases/genetics , Retrospective Studies , Young AdultSubject(s)
Choroid/pathology , Microvascular Density/physiology , Refractive Errors/pathology , Aging , Female , Humans , Male , Tomography, Optical CoherenceABSTRACT
To determine the parameters of the anterior segment of eyes that are significantly associated with the refractive error in healthy young Japanese university students. This was a cross-sectional observational study of 229 healthy Japanese university students (men: women,147:82) whose age ranged between 20 to 29 years. Univariate and multivariate linear regression analyses were performed to identify the factors that were significantly correlated with the refractive error. The independent variables included age, sex, axial length, anterior chamber depth, corneal diameter, curvature of anterior surface of cornea, and central corneal thickness. The mean refractive error (spherical equivalent) was -4.1 ± 2.7 diopters (D) with a range of -12.5 to +0.5 D, and the mean axial length was 25.4 ± 1.3 mm with a range of 22.4 to 29.0 mm. Pearson univariate correlation analysis found that the refractive error was significantly and negatively correlated with the axial length (R = -0.82, P < 0.001), deeper anterior chamber (R = -0.30, P < 0.001), and larger corneal diameter (R = -0.21, P = 0.001). Multiple regression analysis showed that the refractive error was significantly associated with a longer axial length (P < 0.001), a deeper anterior chamber (P < 0.001), and a flatter corneal curvature (P < 0.001).The biometric values of the anterior segment of the eyes should make the eye more hyperopic which would reduce the myopia-inducing lengthening of the axial length.
Subject(s)
Anterior Chamber/pathology , Biometry , Refractive Errors/pathology , Students , Universities , Adult , Axial Length, Eye , Female , Humans , Japan , Male , Multivariate Analysis , Young AdultABSTRACT
In this paper, an analytical closed-form formula for the design of freeform lenses free of spherical aberration and astigmatism is presented. Given the equation of the freeform input surface, the formula gives the equation of the second surface to correct the spherical aberration. The derivation is based on the formal application of the variational Fermat principle under the standard geometrical optics approximation.
Subject(s)
Astigmatism/pathology , Lens, Crystalline/pathology , Optics and Photonics , Refractive Errors/pathology , HumansABSTRACT
PURPOSE: To assess the repeatability and agreement of anterior segment measurements between an optical biometer (IOLMaster 700) using swept-source optical coherence tomography and a Scheimpflug-Placido tomographer (Sirius) in patients scheduled for corneal refractive surgery. SETTING: Eye Hospital of Wenzhou Medical University, Zhejiang, China. DESIGN: Prospective case series. METHODS: The parameters, including the central corneal thickness (CCT), anterior chamber depth (ACD), aqueous depth, keratometry (K) values, astigmatism, J0 (Jackson cross-cylinder with axes at 180 degree and 90 degrees) and J45 vectors (Jackson cross-cylinder with axes at 45 degrees and 135 degrees), and horizontal corneal diameter, were measured 3 times per instrument. The intraobserver repeatability was assessed using test-retest repeatability, the coefficient of variation (CoV), and the intraclass correlation coefficient (ICC). Paired t tests were used to compare the difference between the 2 methods. Agreement was evaluated using Bland-Altman analyses. RESULTS: The study enrolled 100 right eyes. All measurements of the 2 devices showed high repeatability. The CoV of all measured parameters was less than 0.93 and the ICC value was more than 0.85. The paired t test did not show a significant difference in CCT, astigmatism, J0 or J45 vector. The mean ACD and aqueous depth were statistically lower with the optical biometer; however, the 95% limits of agreement (LoA) were low (from -0.20 to -0.03 mm). The K and corneal diameter values obtained using the optical biometer were higher by 0.1 diopter and 0.1 mm, respectively, but with narrow 95% LoA. CONCLUSIONS: The optical biometer and the Scheimpflug-Placido tomographer showed high repeatability for all anterior segment measurements. The measured parameters showed good agreement and could be used interchangeably.
Subject(s)
Anterior Eye Segment/pathology , Biometry/instrumentation , Corneal Diseases/pathology , Corneal Topography/methods , Refractive Errors/pathology , Tomography, Optical Coherence/methods , Adolescent , Adult , Female , Humans , Male , Prospective Studies , Reproducibility of Results , Young AdultABSTRACT
BACKGROUND: We aim to assess if refractive error or age may influence the repeatability of measurements using a swept-source biometer. METHODS: A total of 61 subjects were evaluated with IOLMaster 700 acquiring measurements of axial length (AL), central corneal thickness (CCT), white-to-white distance (WTW), anterior aqueous depth (AQD), lens thickness (LT), and keratometry (K) readings. Repeatability was evaluated classifying the sample according to the refractive state and age by the calculation of the within-subject standard deviation (Sw), coefficient of repeatability, and intraclass correlation coefficient. RESULTS: Very similar Sw was acquired among groups for AL, CCT, and WTW. Differences found for AQD, LT, keratometry and astigmatism among refractive and age groups were not clinically significant. Refractive groups obtained a Sw for AQD between 0.016 and 0.026, while for LT was between 0.023 and 0.029 mm. Besides, Sw showed values from 0.014 to 0.029 mm for keratometry. Age groups obtained a Sw of 0.025 and 0.016 mm for AQD, and 0.029 and 0.018 mm for LT, respectively. Sw was 0.019 vs 0.018 mm for K1, 0.014 vs 0.031 mm for K2. CONCLUSIONS: IOLMaster 700 showed good repeatability for biometric and keratometric parameters in eyes classified according to their refractive error or age.
Subject(s)
Aging/physiology , Biometry/instrumentation , Biometry/methods , Refractive Errors/pathology , Adult , Age Factors , Axial Length, Eye/anatomy & histology , Female , Humans , Lens, Crystalline/anatomy & histology , Male , Middle Aged , Reproducibility of Results , Tomography, Optical Coherence , Young AdultABSTRACT
PURPOSE: To observe features of the posterior vitreous and vitreoretinal interface in highly myopic eyes with retinoschisis using enhanced vitreous imaging optical coherence tomography. METHODS: Comprehensive ophthalmologic examination and enhanced vitreous imaging optical coherence tomography were performed in 77 eyes of 63 patients with highly myopic retinoschisis. Two different modes of spectral domain optical coherence tomography were employed to estimate retinoschisis and the posterior vitreous features in optical coherence tomography images, respectively. The types and distribution of vitreoretinal interface abnormalities were also analyzed. RESULTS: Complete posterior vitreous detachment (PVD) was identified in 55 eyes (71.4%) with a Weiss ring. Residual cortex was found in 39 eyes (70.9%) with complete PVD. Vitreoretinal interface changes, including vitreoretinal adhesion and epiretinal membrane (ERM), most frequently appeared in the macular area (47.3%), followed by the inferior arched vessels region (34.5%). In partial PVD eyes, vitreoretinal traction, vitreoretinal adhesion, and epiretinal membrane tended to be observed in the inferior and superior arched vessels regions (54.5 and 40.9%, respectively). Among all types of vitreoretinal interface abnormalities, epiretinal membrane comprised the largest proportion (46.8%) despite the status of PVD. The presence of inner layers of retinoschisis connoted a relatively high possibility of vitreoretinal interface abnormalities occurring. CONCLUSION: Enhanced vitreous imaging optical coherence tomography reveals a high prevalence of vitreoretinal interface abnormalities in highly myopic eyes with retinoschisis. Vitreous cortex tends to remain on the macular area in eyes with complete PVD. Our findings may lead to better guidance for the surgical treatment of highly myopic retinoschisis.
Subject(s)
Myopia, Degenerative/diagnostic imaging , Retinoschisis/diagnostic imaging , Adult , Aged , Aged, 80 and over , Epiretinal Membrane/diagnostic imaging , Epiretinal Membrane/pathology , Humans , Male , Middle Aged , Myopia, Degenerative/complications , Myopia, Degenerative/pathology , Refractive Errors/diagnostic imaging , Refractive Errors/pathology , Retinoschisis/complications , Retinoschisis/pathology , Tomography, Optical Coherence/methods , Vitreous Body/diagnostic imagingABSTRACT
The present study was conducted to investigate the effect of parental refractive errors on myopic children in Korean families using a nationally representative survey. We used the ophthalmologic examination dataset of the Korean National Health and Nutrition Examination Surveys IV and V, a nationwide population-based cross-sectional study using a complex, stratified, multistage, probability cluster survey, which were performed from 2008-2012. We included 3,862 children from 5-18 years of age from 2,344 families without any ocular trauma, surgical history, or cataract affecting refractive errors. The generalized estimating equation was conducted to assess the association of refractive errors among children and their parents. Among 3,862 children, 2,495 had myopia, which was 64.6% prevalence. There were 208 children with high myopia (5.4%). The prevalence rate ratio (PRR) for pediatric myopia and high myopia with myopic parents was 1.34 (95% confidence intervals [CI] 1.24-1.45) and 3.11 (95% CI 1.93-5.01), respectively. The PRR of myopia and high myopia in children significantly increased to 1.37 (95% CI 1.04-1.81) and 11.41 (95% CI 6.24-20.88), as the degree of parental myopia increased (P < 0.001, respectively). Children with two myopic parents were more myopic than those with only one myopic parent (P < 0.001, respectively). In addition to parental myopia, the age of the child and household income were also significant risk factors for all degrees of pediatric myopia in a family (P ≤ 0.005, respectively). In conclusion, Korean children showed high prevalence of myopia. Children with myopic parents showed a significantly greater risk for myopia and high myopia.