Publications by authors named "Gerard Nah"

Purpose: To examine the associations between higher order aberrations (HOAs), visual performance, demographics, and ocular characteristics in a young Asian population with high myopia.

Methods: This was a retrospective review of military pre-enlistees conducted between March 2014 to September 2018. Visual acuity and contrast sensitivity were tested under photopic, mesopic and simulated night conditions.

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Importance: This study reports outcomes of myopic photorefractive keratectomy (PRK) in a mainly ethnic Chinese population in Singapore.

Background: To assess the incidence and associations of corneal haze and endothelial cell count (ECC) loss up to 12 months after PRK.

Design: This was a retrospective case series conducted in a tertiary eye centre.

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Purpose: To determine the type and prevalence of peripheral retinal changes and its relationship with axial length (AL) in a population of young Asian adult males.

Methods: This was a cross-sectional study of male subjects aged between 19 and 25 years old. High myopes [spherical equivalent refraction, (SER) < -6.

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Objective: To evaluate the relationship between both spherical equivalent (SE) and retinal thickness (RT) on best-corrected visual acuity (BCVA) among young Asian adult men under photopic, mesopic, and simulated night-vision goggle (NVG) lighting conditions.

Design: Community-based cross-sectional study.

Participants: Total of 698 myopic and 148 emmetropic subjects.

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Purpose: To assess the incidence and risk factors for early corneal haze after myopic photorefractive keratectomy (PRK).

Setting: Tertiary eye center, Singapore.

Design: Retrospective case series.

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Purpose: To determine the prevalence and risk factors of myopic maculopathy and specific optic disc and macular changes in highly myopic eyes of young Asian adults and their impact on visual acuity.

Design: Prospective cross-sectional study.

Methods: In total, 593 highly myopic (spherical equivalent refraction [SER] less than -6.

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Purpose: To describe the topography and predictors of peripapillary choroidal thickness (PPCT) in highly myopic eyes of young, healthy, Asian subjects.

Methods: A total of 870 young male subjects aged 21.63 ± 1.

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Purpose: To determine the distribution of choroidal thickness (CT) and ocular factors associated with CT in high myopic eyes in comparison with emmetropic eyes of young healthy adults.

Methods: A case-control study of 648 young, male subjects, including 520 high myopes and 128 emmetropes. Choroidal imaging was performed using enhanced depth imaging spectral domain optical coherence tomography.

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Purpose: Despite a high prevalence of myopia among young East Asian adults, there is a lack of data on the myopic retina structure-function relationship in this group. We examined the association between optical coherence tomography (OCT) and electroretinogram (ERG) measurements in highly myopic young Asian adults to provide this information and also determined if OCT can be used as an alternative screening tool to assess retinal function in young myopic adults.

Methods: This was a prospective study comprising young adults aged between 18 and 25 years with spherical equivalent refraction of worse than -6.

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Purpose: To determine the differences in prevalence rates of refractive errors in young Singaporean males over a 13-year period between 1996-1997 and 2009-2010 METHODS: Non-cycloplegic autorefraction data were obtained in a survey of 15,085 young male subjects (mean age 19.5 ± 1.4 years, range 16-25 years) in 1996-1997 using a Nikon NRK-8000 autorefractor.

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Introduction: The high prevalence of myopia among Asians led the Republic of Singapore Air Force (RSAF) to introduce photorefractive keratectomy (PRK) as a means of enlarging its pilot recruitment pool at the end of 2005. This study aims to address the efficacy and safety of PRK performed on young Asian patients with low-moderate myopia, as well as audit the RSAF's corneal refractive surgery (CRS) program.

Methods: This is a retrospective case series of 149 eyes of 76 consecutive patients that underwent PRK as part of the RSAF CRS program over the 5-yr period from 1 January 2006 to 31 December 2010.

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Introduction: This study describes the pathologic changes in the retina of a group of young Asian subjects with myopia worse than -10 diopters spherical equivalent (SE) refraction.

Materials And Methods: The study population consists of 20 male subjects undergoing preemployment screening for public service for a 1-year period from 2009 to 2010. A detailed series of visual tests of function, fundus examination and grading, ocular biometry and posterior segment optical coherence tomography were performed for all eyes.

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Background: Phakic intraocular lens (PIOL) implantation is a surgical option for correction of refractive errors. PIOLs can be use to correct myopia, hyperopia, and astigmatism. It is a surgical option available to patients in addition to methods such as laser cornea refractive surgery, e.

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Dengue fever is the most prevalent vector-borne flavivirus infection in humans. Its ocular manifestations have only recently been reported with increasing frequency. We present a case of an air force rotary wing pilot who presented with dengue-related maculopathy and decrement in visual function.

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We report 13 cases of ophthalmic complications resulting from dengue infection in Singapore. We performed a retrospective analysis of a series of 13 patients with dengue fever who had visual impairment. Investigations included Humphrey automated visual field analyzer, Amsler charting, fundus fluorescein angiography, and optical coherence tomography.

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Purpose: To compare the complications and subjective experience of patients having argon laser suturelysis (LS) with those of patients having needle suturelysis (NS) for corneal astigmatism after extracapsular cataract extraction (ECCE).

Setting: Department of Ophthalmology, Tan Tock Seng Hospital, Singapore.

Methods: This prospective study comprised 30 patients (30 eyes) with more than 3.

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