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The increasing prevalence of myopia over the past few decades and its association with potential ocular complications make myopia an important research topic. The present work is concerned with the structural and functional characteristics of a group of myopic and emmetropic individuals. The technical experiments in this work investigated firstly the effect of instrument alignment on peripheral refraction measurements and revealed that the corneal vertex was an acceptable alignment position of the Shin-Nippon NVision-K 5001 autorefractor, allowing consistent alignment with other instruments used in this research. Secondly, spectacles could be used to provide comparable vision to contact lenses in the visual performance studies. In the main experimental parts of this work, visual performance and multiple aspects of ocular structure were assessed across a wide range of eccentricities along the horizontal and vertical meridians within the same eyes. The structural properties of the myopic eye were measured through central and peripheral autorefraction, and through cornea to retina dimensions using non-contact biometry. In addition, the central and peripheral resolution acuities of myopic and emmetropic eyes for high and low contrast levels were investigated. Our structural and functional measurements revealed relatively prolate myopic eyes with reduced high contrast resolution acuity, compared to emmetropic eyes. Moreover, multiple regression analyses were performed at the fovea and outermost retinal eccentricities common to all core experiments but revealed no strong relationship between the structure and function of the myopic eye. Finally, regarding asymmetry, the nasal and superior retinae were found to be longer and to perform better in comparison to the temporal and superior retinae respectively.

The increasing prevalence of myopia over the past few decades and its association with potential ocular complications make myopia an important research topic. The present work is concerned with the structural and functional characteristics of a group of myopic and emmetropic individuals. The technical experiments in this work investigated firstly the effect of instrument alignment on peripheral refraction measurements and revealed that the corneal vertex was an acceptable alignment position of the Shin-Nippon NVision-K 5001 autorefractor, allowing consistent alignment with other instruments used in this research. Secondly, spectacles could be used to provide comparable vision to contact lenses in the visual performance studies. In the main experimental parts of this work, visual performance and multiple aspects of ocular structure were assessed across a wide range of eccentricities along the horizontal and vertical meridians within the same eyes. The structural properties of the myopic eye were measured through central and peripheral autorefraction, and through cornea to retina dimensions using non-contact biometry. In addition, the central and peripheral resolution acuities of myopic and emmetropic eyes for high and low contrast levels were investigated. Our structural and functional measurements revealed relatively prolate myopic eyes with reduced high contrast resolution acuity, compared to emmetropic eyes. Moreover, multiple regression analyses were performed at the fovea and outermost retinal eccentricities common to all core experiments but revealed no strong relationship between the structure and function of the myopic eye. Finally, regarding asymmetry, the nasal and superior retinae were found to be longer and to perform better in comparison to the temporal and superior retinae respectively.

Influência da ceratometria e profundidade de câmara anterior obtidas por interferometria de coerência parcial e por sistema Scheimpflug na acurácia do poder dióptrico de lente intraocular multifocal calculada para emetropia [Tese]. São Paulo: Faculdade de Medicina, Universidade de São Paulo; 2018. Objetivo: Verificar se a ceratometria média (K) e a profundidade de câmara anterior (ACD) obtidos por biometria óptica (IOLMaster® 500) e por sistema Scheimpflug (Pentacam® HR) influenciam na predição do cálculo do poder dióptrico de LIO multifocal programada para emetropia. Métodos: Estudo clínico retrospectivo de 198 olhos portadores de catarata senil, tratados com facoemulsificação e implante de LIO multifocal. A diferença entre o valor da ¨LIO ideal¨, previsto pela fórmula biométrica de HAIGIS para emetropia e o poder dióptrico da LIO implantada foi denominada \"desvio teórico da emetropia\" (TDE). Foram testados quatro cenários de cálculo de LIOs, combinando as medidas K e ACD obtidas com os dois dispositivos. Resultados: No trigésimo dia de pós-operatório, o equivalente esférico foi 0 D em 118 dos 198 olhos (60%). O IOL Master® 500 e Pentacam® HR diferiram em relação à média de K (delta 0,09 ± 0,02 D, p < 0,001) e ACD (delta 0,08 ± 0,01 mm; p < 0,001). De acordo com a análise de covariância, o TDE foi 0,17 ± 0,01 D para K e ACD mensurados com IOL Master® 500; 0,27 ± 0,01 D para K e ACD obtidos com Pentacam® HR; 0,15 ± 0,01 D para K gerados com IOL Master® e ACD medidos com Pentacam® HR e 0,28 ± 0,01 D para K mensurado com Pentacam® HR e ACD obtido com IOL Master®. O TDE foi menor quando K foi medido com IOL Master® 500, independente de qual dispositivo foi usado para medir ACD. Conclusões: As predições foram menos confiáveis usando o K gerado pelo Pentacam® HR (diferença média > 0,25D), a despeito de qual equipamento tenha gerado a ACD / Objective: To compare the postoperative refractive predictability of IOL Master® 500 and Pentacam® HR based on K and ACD values in eyes with indication for multifocal IOLs. Methods: Clinical retrospective study of 198 consecutive eyes treated with phacoemulsification and multifocal IOL implantation. The difference between the predicted value and the ideal IOL diopter was termed theoretical deviation from emmetropia (TDE). Using Haigis\' formula, the IOL closest to emmetropia was chosen. Four lens calculation scenarios were tested by combining K and ACD measurements obtained with the two devices. Results: On the 30th postoperative day, the spherical equivalent was 0 D in 118 of the 198 eyes (60%). IOL Master® and Pentacam® HR differed with regard to mean K (delta 0.09 ± 0.02 D; p < 0.001) and ACD (delta 0.08 ± 0.01 mm; p < 0.001). According to the analysis of covariance, TDE was 0.17 ± 0.01 D for K and ACD measured with IOL Master®, 0.27 ± 0.01 D for K and ACD measured with Pentacam HR; 0.15 ± 0.01 D for K measured with IOL Master® and ACD measured with Pentacam® HR, and 0.28 ± 0.01 D for K measured with Pentacam HR and ACD measured with IOL Master®. Mean K was the only statistically significant factor (p < 0.001). Thus, TDE was smaller when K was measured with IOL Master® 500, regardless of which device was used to measure ACD. Conclusion: Predictions were less reliable using the K generated by Pentacam® HR (average difference > 0,25D), regardless of which equipment has generated the ACD

<p>Stopa prematuriteta konstantno raste, a sve vi&scaron;e prevremeno rođenih beba koje prežive neonatalni i perinatalni period zahteva adekvatno sistemsko i oftalmolo&scaron;ko praćenje i tretman. Prematuritet sam po sebi, predstavlja rizik za razvoj vida. Taj rizik dodatno povećava prisustvo prematurne retinopatije i refraktivnih mana. Skrining i tretman promena na retini u sklopu prematuriteta, kao i optička korekcija refraktivnih mana obezbeđuju uslove za razvoj vida. Cilj ovog istraživanja je bio utvrditi promene biometrijskih karakteristika oka prematurusa, sa i bez prematurne retinopatije, tokom &scaron;estogodi&scaron;njeg praćenja, utvrditi refraktivni status ove dve grupe dece sa &scaron;est godina, te povezati promene biometrijskih karakteristika oka sa refrakcijom. U ispitivanje je uključeno 192 prevremeno rođena deteta (384 oka). Vr&scaron;ena su tri pregleda, u uzrastu od 3 meseca, 12 meseci i 6 godina starosti. Nakon prvog pregleda ispitivani uzorak je, u zavisnosti od nalaza na očnom dnu, podeljen na bebe sa prematurnom retinopatijom i bebe bez ovog oboljenja, a kako bi se uporedile proučavane karakteristike. U sva tri navedena uzrasta je pregledano očno dno i merene su tri glavne biometrijske karakteristike koje utiču na refraktivni status: aksijalna dužina oka, dubina prednje očne komore i debljina očnog sočiva. Sa &scaron;est godina je određena refrakcija, uključujući zakrivljenost rožnjače odnosno kornealni astigmatizam, vidna o&scaron;trina bez korekcije refraktivne mane, a zatim i nakon korekcije. Ostali neophodni podaci su dobijeni iz medicinske dokumentacije. Pokazano je da prematurna retinopatija utiče na refraktivni status i vidni ishod sa &scaron;est godina, pre svega uticajem na zakrivljenost rožnjače, aksijalnu dužinu oka i dubinu prednje očne komore, dok su promene debljine očnog sočiva bez posebnog značaja. Vidne o&scaron;trine oba oka u pred&scaron;kolskom uzrastu prevremeno rođene dece sa prematurnom retinopatijom su statistički značajno manje kada se uporede sa vidnim o&scaron;trinama prevremeno rođene dece bez retinopatije, ali razlika u ovim dvema vrednostima gubi statističku značajnost nakon optičke korekcije. Učestalost astigmatizma u prematurnoj populaciji sa 6 godina je visoka, a od onih koji imaju astigmatizam u tom uzrastu, vi&scaron;e od dve trećine je imalo prematurnu retinopatiju. Ukupna učestalost miopije, hipermetropije i emetropije u prematurnoj populaciji sa 6 godina je 18,9%, 54,7% i 13,2%, a preostalih 13,2% su anizometropi. U vi&scaron;e od trećine dece, sa prematurnom retinopatijom u najranijem uzrastu, sa &scaron;est godina postoji gubitak vidne sposobnosti, koji je najče&scaron;će blag, no može biti i potpun.</p> / <p>The number of babies born prematurely is constantly growing, so more and more of them need appropriate systemic and ophthalmologic monitoring and treatament. Prematurity itself, represents a risk for the development of vision. This risk further reinforces the presence of retinopathy of prematurity and refractive errors. Screening and treatment of retinopathy, as well as optical correction of refractive errors provide adequate conditions for the development of vision. The aim of this study was to determine changes of biometric features of eyes of the prematurely born infants, with and without retinopathy of prematurity, during the six-year follow-up. We also want to determine the refractive status of these two groups of children in the six year, and to link changes of biometric features with their eye refraction. The study included 192 prematurely born children (384 eyes). The examinations were performed at 3 months, 12 months and 6 years and they included fundus examination and measurements of the ocular axial length, anterior chamber depth and lens thickness. After dividing the subjects into two groups, based on the results of the fundus examination at 3 months, the results of the children with and without retinopathy were compared. At the age of six we also determine the refraction of eyes, including the curvature of the cornea and corneal astigmatism, visual acuity without correction of refractive error, and then after it. Other necessary data were obtained from medical documentation. It is shown that retinopathy of prematurity affects the refractive status and visual outcome at sixth year, primarily by the changes of curvature of the cornea, the axial length of the eye and the depth of the anterior chamber, while the change in the lens thickness has no significance. Visual acuity in both eyes in the preschool age preterm born children with retinopathy of prematurity are significantly less, when compared to visual acuity in preterm infants without retinopathy, but the difference in these two values lost statistical significance after optical correction. The rate of astigmatism in preterm population of six years is high, and of those who have astigmatism in this age group, more than two-thirds had retinopathy of prematurity. The overall incidence of myopia, hypermetropia and emetropia in the prematurely born, six years old children is 18.9%, 54.7% and 13.2%, and the remaining 13.2% have anisometropia. In more than a third of children with retinopathy of prematurity at an early age, with six years, there has been loss of visual acuity, which is usually mild, but it can be complete.</p>

No / The eye rotation approach for measuring peripheral eye length leads to concern about whether the rotation influences results, such as through pressure exerted by eyelids or extra-ocular muscles. This study investigated whether this approach is valid. Peripheral eye lengths were measured with a Lenstar LS 900 biometer for eye rotation and no-eye rotation conditions (head rotation for horizontal meridian and instrument rotation for vertical meridian). Measurements were made for 23 healthy young adults along the horizontal visual field (+/- 30 degrees ) and, for a subset of eight participants along the vertical visual field (+/- 25 degrees ). To investigate the influence of the duration of eye rotation, for six participants measurements were made at 0, 60, 120, 180 and 210 s after eye rotation to +/- 30 degrees along horizontal and vertical visual fields. Peripheral eye lengths were not significantly different for the conditions along the vertical meridian (F1,7 = 0.16, p = 0.71). The peripheral eye lengths for the conditions were significantly different along the horizontal meridian (F1,22 = 4.85, p = 0.04), although not at individual positions (p >/= 0.10) and were not important. There were no apparent differences between the emmetropic and myopic groups. There was no significant change in eye length at any position after maintaining position for 210 s. Eye rotation and no-eye rotation conditions were similar for measuring peripheral eye lengths along horizontal and vertical visual field meridians at +/- 30 degrees and +/- 25 degrees , respectively. Either condition can be used to estimate retinal shape from peripheral eye lengths.