Peng Tee Khaw

Peng Tee Khaw
Moorfields Eye Hospital and UCL Institute of Ophthalmology · NIHR Biomedical Research Centre

PhD FRCP FRCS FRCOphth FRCPath FCOptom Hon DSc FRSB FARVO FMedSci

About

611
Publications
99,803
Reads
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23,749
Citations
Additional affiliations
April 2006 - March 2016
National Institute for Health Research
Position
  • Director Biomedical Research Centre Ophthalmology
January 2003 - present
UCL Institute of Ophthalmology
Position
  • Professor
Description
  • https://iris.ucl.ac.uk/iris/browse/profile?upi=PTKHA24
January 1998 - December 2012

Publications

Publications (611)
Article
Full-text available
New in vitro prototypes (PK-EyeTM) were tested with and without eye movement to under- stand diffusion and convection effects on intraocular clearance. Port placement in front ((i) ciliary inflow model) and behind the model lens ((ii) posterior inflow model) was used to study bevacizumab (1.25 mg/50 μL) and dexamethasone (0.1 mg/100 μL) in phosphat...
Article
Full-text available
Prcis: A literature review of SLT energy dose response found no definitive relationship between IOP reduction with respect to total or pulse energy, race, pigmentation, or application pattern. Purpose: Selective laser trabeculoplasty (SLT) is a safe and effective treatment for lowering intraocular pressure (IOP). While evidence is mounting for t...
Article
Full-text available
Vision impairment (VI) can have wide ranging economic impact on individuals, households, and health systems. The aim of this systematic review was to describe and summarise the costs associated with VI and its major causes. We searched MEDLINE (16 November 2019), National Health Service Economic Evaluation Database, the Database of Abstracts of Rev...
Article
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Importance: Understanding the effects of modifiable risk factors on risk for multiple sclerosis (MS) and associated neurodegeneration is important to guide clinical counseling. Objective: To investigate associations of alcohol use, smoking, and obesity with odds of MS diagnosis and macular ganglion cell layer and inner plexiform layer (mGCIPL) t...
Article
Topic Corneal endothelial cell density (ECD) loss following glaucoma surgery with or without cataract surgery. Clinical relevance Corneal ECD loss may occur due to intraoperative surgical trauma in glaucoma surgery or postoperatively with chronic endothelial cell trauma or irritation. Methods Trabeculectomy, glaucoma filtration surgery or microin...
Article
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Background We undertook a Grand Challenges in Global Eye Health prioritisation exercise to identify the key issues that must be addressed to improve eye health in the context of an ageing population, to eliminate persistent inequities in health-care access, and to mitigate widespread resource limitations. Methods Drawing on methods used in previou...
Article
Background: We undertook a Grand Challenges in Global Eye Health prioritisation exercise to identify the key issues that must be addressed to improve eye health in the context of an ageing population, to eliminate persistent inequities in health-care access, and to mitigate widespread resource limitations. Methods: Drawing on methods used in previ...
Article
Full-text available
Purpose: Air pollution is associated with chronic diseases of later life. Cataract is the most common cause of blindess globally. It is biologically plausible that cataract risk is increased by pollution exposure. Therefore, the relationship between air pollution and incident cataract surgery was examined. Methods: This was a prospective, observ...
Article
Full-text available
Objective We aim to systematically assess and compare corneal endothelial cell density (ECD) loss in patients with glaucoma following glaucoma surgery and cataract surgery. Introduction Corneal ECD loss may occur due to intraoperative surgical trauma in glaucoma surgery or postoperatively with chronic endothelial cell trauma or irritation. Corneal...
Article
Background/aims: The reason for visual impairment in patients with nanophthalmos and posterior microphthalmos is not completely understood. Therefore, this study aims to investigate foveal structure, and the impact of demographic, clinical and imaging parameters on best-corrected visual acuity (BCVA) in these conditions. Methods: Sixty-two eyes...
Article
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Background Perimetry is important in the management of children with glaucoma, but there is limited evidence-based guidance on its use. We report an expert consensus-based study to update guidance and identify areas requiring further research. Methods Experts were invited to participate in a modified Delphi consensus process. Panel selection was b...
Chapter
Ocular rigidity can be defined as the resistance of the globe to distension. Ocular rigidity can have a profound influence on different types of ocular surgery. There are many variables that lead to distension of the eye, with change in volume being considered the most major variable. Surgery itself can change the eye’s resistance to distension. Ex...
Article
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Optical Coherence Tomography (OCT) enables non-invasive imaging of the retina and is used to diagnose and manage ophthalmic diseases including glaucoma. We present the first large-scale genome-wide association study of inner retinal morphology using phenotypes derived from OCT images of 31,434 UK Biobank participants. We identify 46 loci associated...
Article
Full-text available
Objective To compare the effectiveness and safety of the MicroShunt versus trabeculectomy in patients with primary open-angle glaucoma (POAG). Design One-year results from a 2-year, prospective, randomized, multicenter, non-inferiority study (NCT01881425) conducted in the USA and Europe. Participants Eligible patients were aged 40–85 years with i...
Article
Neural cell death is the main feature of all retinal degenerative disorders that lead to blindness. Despite therapeutic advances, progression of retinal disease cannot always be prevented, and once neuronal cell damage occurs, visual loss cannot be reversed. Recent research in the stem cell field, and the identification of Müller glia with stem cel...
Article
Full-text available
p>Background: associations between microvascular variation and chronic kidney disease (CKD) have been reported previously. Non-invasive retinal fundus imaging enables evaluation of the microvascular network and may offer insight to systemic risk associated with CKD. Methods: retinal microvascular parameters (fractal dimension [FD] – a measure of t...
Article
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Primary open-angle glaucoma (POAG), is a heritable common cause of blindness world-wide. To identify risk loci, we conduct a large multi-ethnic meta-analysis of genome-wide association studies on a total of 34,179 cases and 349,321 controls, identifying 44 previously unreported risk loci and confirming 83 loci that were previously known. The majori...
Article
Primary open-angle glaucoma (POAG), is a heritable common cause of blindness world-wide. To identify risk loci, we conduct a large multi-ethnic meta-analysis of genome-wide association studies on a total of 34,179 cases and 349,321 controls, identifying 44 previously unreported risk loci and confirming 83 loci that were previously known. The majori...
Article
Full-text available
Purpose To examine the association of alcohol consumption and type of alcoholic beverage with incident cataract surgery in two large cohorts. Design Longitudinal observational study Participants We included 469,387 participants of UK Biobank with a mean age of 56 years, and 23,162 participants of EPIC-Norfolk with a mean age of 59 years. Methods...
Article
Background The WHO VISION 2020 global initiative against blindness, launched in 2000, prioritised childhood visual disability by aiming to end avoidable childhood blindness by 2020. However, progress has been hampered by the global paucity of epidemiological data concerning childhood visual disability. The British Childhood Visual Impairment and Bl...
Article
Aim To examine the associations of air pollution with both self-reported age-related macular degeneration (AMD), and in vivo measures of retinal sublayer thicknesses. Methods We included 115 954 UK Biobank participants aged 40–69 years old in this cross-sectional study. Ambient air pollution measures included particulate matter, nitrogen dioxide (...
Article
p>The diagnosis of multiple sclerosis is based on a combination of clinical and paraclinical tests. The potential contribution of retinal optical coherence tomography (OCT) has been recognized. We tested the feasibility of OCT measures of retinal asymmetry as a diagnostic test for multiple sclerosis at the community level. In this community-based s...
Article
Full-text available
Background Current methods to diagnose neurodegenerative diseases are costly and invasive. Retinal neuroanatomy may be a biomarker for more neurodegenerative processes and can be quantified in vivo using optical coherence tomography (OCT), which is inexpensive and noninvasive. We examined the association of neuroretinal morphology with brain MRI im...
Article
Full-text available
The diagnosis of multiple sclerosis is based on a combination of clinical and paraclinical tests. The potential contribution of retinal optical coherence tomography (OCT) has been recognized. We tested the feasibility of OCT measures of retinal asymmetry as a diagnostic test for multiple sclerosis at the community level. In this community-based stu...
Article
Highlights • Dual acting therapeutic proteins may be a better strategy than drug combinations for treatment of chronic retinal diseases. •Several targets to treat neovascularisation and inflammation have been identified. •A dual acting molecule to increase the duration of action in the vitreous has potential for treatment of chronic retinal diseas...
Article
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Proteins and peptides have emerged in recent years to treat a wide range of multifaceted diseases such as cancer, diabetes and inflammation. The emergence of polypeptides has yielded advancements in the fields of biopharmaceutical production and formulation. Polypeptides often display poor pharmacokinetics, limited permeability across biological ba...
Article
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Purpose A major challenge in glaucoma research is the lack of reproducible animal models of RGC and optic nerve damage, the characteristic features of this condition. We therefore examined the glaucomatous responses of two different rat strains, the Brown Norway (BN) and Lister Hooded (LH) rats, to high intraocular pressure (IOP) induced by injecti...
Preprint
Full-text available
Optical Coherence Tomography (OCT) enables non-invasive imaging of the retina and is often used to diagnose and manage multiple ophthalmic diseases including glaucoma. We present the first large-scale quantitative genome-wide association study of inner retinal morphology using phenotypes derived from OCT images of 31,434 UK Biobank participants. We...
Article
Full-text available
Introduction: Vision impairment (VI) places a burden on individuals, health systems and society in general. In order to support the case for investing in eye health services, an updated cost of illness study that measures the global impact of VI is necessary. To perform such a study, a systematic review of the literature is needed. Here we outline...
Article
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The processes involved in ocular fibrosis after disease or ocular tissue injury, including surgery play an important part in the development or failure of treatment of most blinding diseases. Ocular fibrosis is one of the biggest areas of unmet need in ophthalmology. Effective anti-scarring therapies could potentially revolutionise the management o...
Article
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Progression to exudative ‘wet’ age-related macular degeneration (exAMD) is a major cause of visual deterioration. In patients diagnosed with exAMD in one eye, we introduce an artificial intelligence (AI) system to predict progression to exAMD in the second eye. By combining models based on three-dimensional (3D) optical coherence tomography images...
Article
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Galectins are carbohydrate binding proteins with high affinity to ß-galactoside containing glycoconjugates. Understanding of the functions of galectins has grown steadily over the past decade, as a result of substantial advancements in the field of glycobiology. Galectins have been shown to be versatile molecules that participate in a range of impo...
Article
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Purpose: Because air pollution has been linked to glaucoma and AMD, we characterized the relationship between pollution and retinal structure. Methods: We examined data from 51,710 UK Biobank participants aged 40 to 69 years old. Ambient air pollution measures included particulates and nitrogen oxides. SD-OCT imaging measured seven retinal layer...
Preprint
Full-text available
OBJECTIVES: To identify the sociodemographic, lifestyle, comorbidity and antihypertensive medication associations with the development of hospitalisation with covid-19 in an English population. DESIGN: Prospective cohort study SETTING: The population-based UK Biobank study was linked to English covid-19 test results. PARTICIPANTS: Individuals resid...
Article
The majority of blinding conditions arise due to chronic pathologies in the retina. During the last two decades, antibody-based medicines administered by intravitreal injection directly into the back of the eye have revolutionised the treatment of chronic retinal diseases characterised by uncontrolled blood vessel growth, e.g. wet age-related macul...
Article
Purpose: Because air pollution has been linked to glaucoma and AMD, we characterized the relationship between pollution and retinal structure. / Methods: We examined data from 51,710 UK Biobank participants aged 40 to 69 years old. Ambient air pollution measures included particulates and nitrogen oxides. SD-OCT imaging measured seven retinal layers...
Article
Full-text available
Current estimates suggest 50% of glaucoma blindness worldwide is caused by primary angle-closure glaucoma (PACG) but the causative gene is not known. We used genetic linkage and whole genome sequencing to identify Spermatogenesis Associated Protein 13, SPATA13 (NM_001166271; NP_001159743, SPATA13 isoform I), also known as ASEF2 (Adenomatous polypos...
Article
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Refractive errors, in particular myopia, are a leading cause of morbidity and disability worldwide. Genetic investigation can improve understanding of the molecular mechanisms that underlie abnormal eye development and impaired vision. We conducted a meta-analysis of genome-wide association studies (GWAS) that involved 542,934 European participants...
Article
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Background/Aims This work aimed to study the effect of long-term intraocular pressure (IOP) fluctuation on visual field (VF) progression 8 years post-trabeculectomy in Asian eyes. Methods This was a retrospective analysis of 8-year post-trabeculectomy data from The Singapore 5-Fluorouracil (5-FU) Study. VFs were analysed using Progressor software...
Chapter
The integrity of ocular anatomy and physiology, the function of the visual system, and the perception of vision, our most prized sense, are intimately connected with our general health. Subtle visual signs and symptoms may therefore be the first manifestation of occult systemic disease. With a basic history and examination of the eyes and vision, t...
Article
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Glaucoma, a disease characterized by progressive optic nerve degeneration, can be prevented through timely diagnosis and treatment. We characterize optic nerve photographs of 67,040 UK Biobank participants and use a multitrait genetic model to identify risk loci for glaucoma. A glaucoma polygenic risk score (PRS) enables effective risk stratificati...
Preprint
Full-text available
We conducted a large multi-ethnic meta-analysis of genome-wide association studies for primary open-angle glaucoma (POAG) on a total of 34,179 cases vs 349,321 controls, and identified 127 independent risk loci, almost doubling the number of known loci for POAG. The majority of loci have broadly consistent effect across European, Asian and African...
Article
Full-text available
Spectral-domain OCT (SD-OCT) provides high resolution images enabling identification of individual retinal layers. We included 32,923 participants aged 40–69 years old from UK Biobank. Questionnaires, physical examination, and eye examination including SD-OCT imaging were performed. SD OCT measured photoreceptor layer thickness includes photorecept...
Article
Purpose Glaucoma is reportedly more frequent in people living in urban areas and more than 91% of the world’s population live in areas with air pollution above WHO recommended limits. However, few studies have examined the association between air pollution and risk of glaucoma. Methods UK Biobank participants aged 40–69 years old completed a detai...
Article
Purpose: Glaucoma is more common in urban populations than in others. Ninety percent of the world's population are exposed to air pollution above World Health Organization (WHO) recommended limits. Few studies have examined the association between air pollution and glaucoma. Methods: Questionnaire data, ophthalmic measures, and ambient residenti...
Article
Purpose To describe the distribution of corneal hysteresis (CH) in a large cohort and explore its associated factors and possible clinical applications. Design Cross-sectional study within the UK Biobank, a large cohort study in the United Kingdom. Participants We analyzed CH data from 93 345 eligible participants in the UK Biobank cohort, aged 40...
Article
Full-text available
Clinical grading systems following glaucoma filtration surgery do not include any effects of the bleb on the intra-ocular pressure and are relatively subjective, therefore carrying the risk of inter and/or intra-observer variability. The main objective of the study is to quantify and model the effect of subconjunctival bleb on flow pressure for ass...
Article
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Purpose: To explore the impact of childhood lensectomy on posterior segment development. Methods: Cross-sectional observational study at children's eye clinics at a tertiary referral center in London, UK. We included 45 children age 4 to 16 years with healthy eyes and 38 who had undergone lensectomy. We acquired posterior segment optical coheren...
Article
Optic nerve head morphology is affected by several retinal diseases. We measured the vertical optic disc diameter (DD) of the UK Biobank (UKBB) cohort (N = 67 040) and performed the largest genome-wide association study (GWAS) of DD to date. We identified 81 loci (66 novel) for vertical DD. We then replicated the novel loci in International Glaucom...
Article
Full-text available
Glaucoma is the leading cause of irreversible blindness with over 70 million people affected worldwide. The surgical management of glaucoma aims to lower intraocular pressure by increasing aqueous outflow facility. The latest manufacturing techniques have allowed for the development of a number of novel implantable devices to improve safety and out...
Article
p>Purpose: To describe and compare associations with macular retinal nerve fiber layer (mRNFL), ganglion cell complex (GCC), and ganglion cell–inner plexiform layer (GCIPL) thicknesses in a large cohort. Design: Cross-sectional study. Participants: We included 42 044 participants in the UK Biobank. The mean age was 56 years. Methods: Spectral-domai...
Article
Full-text available
Intravitreal injections have become the cornerstone of retinal care and one of the most commonly performed procedures across all medical specialties. The impact of hydrodynamic forces of intravitreal solutions when injected into vitreous or vitreous substitutes has not been well described. While computational models do exist, they tend to underesti...
Article
Purpose: To describe and compare associations with macular retinal nerve fiber layer (mRNFL), ganglion cell complex (GCC), and ganglion cell-inner plexiform layer (GCIPL) thicknesses in a large cohort. Design: Cross-sectional study. Participants: We included 42 044 participants in the UK Biobank. The mean age was 56 years. Methods: Spectral-...
Article
Therapeutic protein medicines have transformed the treatment of blinding diseases (e.g. age-related macular degeneration, AMD) during the last 1–2 decades. Many blinding conditions such as AMD are chronic; and require multiple intravitreal injections over a long period to achieve a high and reproducible dose needed for clinical benefit. Prolonging...
Article
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Purpose: Minimally invasive glaucoma surgery (MIGS) devices that drain into the subconjunctival space can be inserted via an ab externo or ab interno approach. Limited experimental data exists as to the impact of either technique on intraocular pressure (IOP) control. We performed microfluidic studies by using ex vivo rabbit eyes to assess the eff...
Article
Purpose: To develop a comprehensive next-generation sequencing panel assay that screens genes known to cause developmental eye disorders and inherited eye disease and to evaluate its diagnostic yield in a pediatric cohort with malformations of the globe, anterior segment anomalies, childhood glaucoma, or a combination thereof. Design: Evaluation...