Yu Xiang George Kong

Yu Xiang George Kong
Royal Victorian Eye and Ear Hospital · Department of Ophthalmology

MBBS, BMedSci, PhD, FRANZCO

About

83
Publications
44,895
Reads
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2,375
Citations
Introduction
Associate Professor George Kong is a glaucoma specialist and general ophthalmologist with research interests in home monitoring of glaucoma, visual field, perimetry, artificial intelligence, minimally invasive glaucoma surgery (MIGS) and complex glaucoma surgeries. He completed glaucoma fellowship in Melbourne AUS and Cambridge UK. He is currently a glaucoma specialist at The Royal Victorian Eye and Ear Hospital.
Additional affiliations
December 2022 - present
The University of Melbourne
Position
  • Clinical Associate Professor
January 2018 - present
Mount Waverley Eye Surgeons
Position
  • Ophthalmologist
Description
  • Glaucoma and Cataract Specialist
March 2017 - present
Royal Victorian Eye and Ear Hospital
Position
  • Consultant

Publications

Publications (83)
Article
Full-text available
Objective To evaluate efficacy and safety outcomes of the Xen 45 gel stent implant over 24 months of follow-up. Methods A retrospective analysis of prospectively collected data from the Fight Glaucoma Blindness observational registry. Complete success (CS) was defined as intraocular pressure (IOP) reduction ≥20% from preoperative and an IOP ≤18 mm...
Article
Full-text available
Purpose: To compare perimetric outcomes of an iPad perimetry app (Melbourne Rapid Fields [MRF]) with those of the Humphrey Field Analyser (HFA) testing children with glaucoma. Methods: Sixteen children diagnosed and treated for glaucoma were recruited to evaluate their perimetric performance over two visits. At each visit, they undertook visual fi...
Article
Purpose: To evaluate the changes in macular vessel density (mVD) loss in primary open-angle glaucoma (POAG) patients with visual field (VF) defects confined to one hemifield. Methods: This longitudinal cohort study used linear mixed models to evaluate the changes in the hemispheric mean total deviation (mTD), mVD, macular ganglion cell complex,...
Article
Full-text available
Background: To determine the 12-month compliance with and retention of home monitoring (HM) with Melbourne Rapid Fields (MRFh) for patients with intermediate age-related macular degeneration (iAMD) and compare visual acuity (VA) and retinal sensitivity (RS) results to clinical measures. Methods: Participants were recruited to a 12-month HM study...
Article
Visual fields are an integral part of glaucoma diagnosis and management. COVID has heightened the awareness of the potential for viral spread with the practice of visual fields modified. Mask artefacts can occur due to fogging of the inferior rim of the trail lens. Fortunately, the risk of airborne transmission when field testing is low. The 24-2c...
Article
Purpose To investigate whether quantitative optical coherence tomography angiography (OCTA) metrics of the superficial/deep macular retina are associated with the development of visual field (VF) loss in the fellow eyes of normal tension glaucoma (NTG) patients with unilateral VF loss. Methods A longitudinal study was conducted in which 61 eyes wi...
Article
Full-text available
Background: Our primary aim is to quantify test reliability and compliance of glaucoma patients to a weekly visual field telemedicine (VFTM) schedule. A secondary aim is to determine concordance of the VFTM results to in-clinic outcomes. Methods: Participants with stable glaucoma in one eye were recruited for a 12 month VFTM trial using the Melbour...
Article
Full-text available
Background/Objectives To evaluate current routine trabeculectomy technique preferences among Australian and New Zealand Glaucoma Society surgeons regularly performing trabeculectomy surgery. Subjects/Methods Survey of experienced surgeons who perform trabeculectomy. Results Forty-nine surgeons (33 male:16 female) participated in the survey. Trabe...
Article
Full-text available
Aim and objective: Developing improved methods for early detection of visual field defects is pivotal to reducing glaucoma-related vision loss. The Melbourne Rapid Fields screening module (MRF-S) is an iPad-based test, which allows suprathreshold screening with zone-based analysis to rapidly assess the risk of manifest glaucoma. The versatility of...
Article
Full-text available
The conventional stimulus for standard automated perimetry is fixed in size, giving elevated contrast thresholds and reduced test reliability in the periphery. Here, we test the hypothesis that appropriate scaling of the size of perimetric stimuli will return fixed thresholds and reduced variability across the visual field. We derived frequency-of-...
Article
Purpose This study determines the short-term compliance to regular home monitoring of macular retinal sensitivity (RS) in intermediate age-related macular degeneration (iAMD). We also compare home-based outcomes with in-clinic outcomes determined using 1. the same tablet device under supervision and 2. the Macular Integrity Assessment (MaIA) microp...
Article
To evaluate the 12-month outcomes of a novel posterior small incision sub-tenon ab interno technique of XEN stent insertion (‘Semi-open’). Consecutive eyes underwent XEN stent insertion with the Semi-open technique by two surgeons between 1st July 2018 and 30th September 2019. All cases received subconjunctival injection of 0.1 mL of mitomycin C 0....
Chapter
Diagnosis of glaucoma requires more than the optic nerve head (ONH) evaluation findings alone, but ONH assessment is crucial to detection of glaucoma, assessment of severity, and monitoring for disease progression. Objective assessment of the ONH must be done independent of other clinical features. This chapter explores the process of examining the...
Preprint
Purpose This study examines the short-term uptake, compliance, and performance of a tablet device used for home monitoring of visual field (VF-Home) by glaucoma patients. Methods Participants who were glaucoma suspects or had stable glaucoma in at least one eye were recruited during a regular clinic review. Baseline in-clinic visual field (VF) was...
Poster
This is a poster from the now cancelled ARVO 2020 meeting. It describes seminal work undertaken by Dr Viney Gupta and his group in Delhi on children having Paediatric Glaucoma. It turns out that children down to 8 yrs old do the iPad test reasonably well just that some give a lot of false positives and fixation errors. We recommend using the avera...
Article
Full-text available
Glaucoma is the world's leading cause of irreversible blindness. An estimated 80 million people are affected worldwide, and the prevalence is increasing.1 Glaucoma is largely asymptomatic in its early stages and is often referred to as the ‘sneak thief of sight’. Early diagnosis is important for preventing irreversible vision loss. While intraocula...
Article
Full-text available
Computed perimetry remains the gold standard of visual field measurement among glaucoma patients. However, several emerging technologies, made possible by advances in computer programming, smartphone, tablet, or virtual reality, allow alternative means of visual function assessment. These new visual tests may one day have a useful complementary rol...
Article
Full-text available
Purpose: To report here a case of uncontrolled glaucoma during third-trimester of pregnancy that was treated successfully with bilateral Xen gel stent insertion. Observations: A 35-year-old woman presented during the third trimester of pregnancy with bilateral uncontrolled primary open angle glaucoma. Her disc examination and visual fields were...
Article
Importance: Driving is a highly visual task and a primary mode of transportation for many people around the world. Background: There appears to be little uniformity of vision standards across the world for driving. We reviewed the basic screening visual requirements for obtaining standard private and commercial driving licences for a total of 70...
Article
Full-text available
Previous studies have demonstrated that intravitreal delivery of brain-derived neurotrophic factor (BDNF) by injection of recombinant protein or by gene therapy can alleviate retinal ganglion cell (RGC) loss after optic nerve injury. BDNF gene therapy can improve RGC survival in experimental models of glaucoma, the leading cause of irreversible bli...
Article
We present a severe sight‐threatening complication from cosmetic intraocular iris implantation, highlighting the dangers of iris implants and medical tourism. Intraocular iris implants are single‐piece silicone prostheses implanted in the anterior chamber. These devices were initially developed for the treatment of aniridia, however, more recently...
Article
Purpose: To establish the medium-term repeatability of the iPad perimetry app Melbourne Rapid Fields (MRF) compared to Humphrey Field Analyzer (HFA) 24-2 SITA-standard and SITA-fast programs. Design: Multicentre longitudinal observational clinical study. Participants: 60 patients (stable glaucoma/ocular hypertension/glaucoma suspects) were rec...
Article
Full-text available
Purpose: To evaluate the use of smartphone-based virtual reality to objectively assess activity limitation in glaucoma. Methods: Cross-sectional study of 93 patients (54 mild, 22 moderate, 17 severe glaucoma). Sociodemographics, visual parameters, Glaucoma Activity Limitation-9 and Visual Function Questionnaire - Utility Index (VFQ-UI) were coll...
Article
Full-text available
Background The refractive outcomes of glaucoma surgeries, particularly their effect on astigmatism, are incompletely understood. Main bodyTrabeculectomy is associated with a considerable amount of with-the-rule astigmatic change in the immediate postoperative period. This is followed by a gradual against-the-rule shift. These changes are altered wi...
Article
Purpose: To evaluate the accuracy and efficiency of Visual Fields Easy (VFE), a free iPad app, for performing suprathreshold perimetric screening. Methods: We performed screening visual fields using a calibrated iPad 2 with the VFE application on 206 subjects (411 eyes): 210 normal (NL), 183 glaucoma (GL) and 18 diabetic retinopathy (DR) at Tilg...
Article
Purpose: Recent developments in electronic technology are making it possible to home monitor the sensitivity of the central visual field using portable devices. We used simulations to investigate whether the higher test frequency afforded by home monitoring improves the early detection of rapid visual field loss in glaucoma and how any benefits mi...
Article
Full-text available
Background In the assessment of a pituitary mass, objective visual field testing represents a valuable means of evaluating mass effect, and thus in deciding whether surgical management is warranted. Case presentation In this vignette, we describe a 73 year-old lady who presented with a three-week history of frontal headache, and ‘blurriness’ in th...
Article
Full-text available
BACKGROUND: In the assessment of a pituitary mass, objective visual field testing represents a valuable means of evaluating mass effect, and thus in deciding whether surgical management is warranted. CASE PRESENTATION: In this vignette, we describe a 73 year-old lady who presented with a three-week history of frontal headache, and 'blurriness' in t...
Article
Importance: This study provides ophthalmologists who manage uveitic glaucoma with important information on factors that can affect the success of surgical management of this challenging disease. Background: This study examines surgical outcomes of trabeculectomy and glaucoma device implant (GDI) surgery for uveitic glaucoma, in particular the ef...
Article
Full-text available
Purpose: To determine the correlation between the perimetric outcomes from perimetry software Melbourne Rapid Fields (MRF) run on an Apple iPad tablet and those from the Humphrey Field Analyzer (HFA). Methods: The MRF software was designed with features including variable fixation and fast thresholding using Bayes logic. Here, we report a cross-se...
Article
Full-text available
Purpose: We hypothesize that: (1) Anterior chamber depth (ACD) is correlated with the relative anteroposterior position of the pupillary image, as viewed from the temporal side. (2) Such a correlation may be used as a simple quantitative tool for estimation of ACD. Methods: Two hundred sixty-six phakic eyes had lateral digital photographs taken...
Article
Full-text available
Purpose: To describe a tangent perimeter developed on an Apple iPad (Melbourne Rapid Field, MRF). Methods: The MRF assays 66 locations over 288 3 188 by having the patient vary fixation. Spot size and background luminance are paired to yield constant thresholds across the field. Spot locations were selected after analysis of 360 patient records. Th...
Article
In this letter we describe a case of persistent elevated IOP following routine cataract surgery caused by proven active HSV uveitis with no corneal signs.
Article
Full-text available
We report a case series of three patients with previous trabeculectomies who developed elevated intraocular pressure (IOP) in the immediate postoperative period after routine Descemet stripping automated endothelial keratoplasty (DSAEK). All patients had functioning trabeculectomies preoperatively, and developed elevated IOP between 41 and 69 mm Hg...
Conference Paper
Purpose: Determine the accuracy and repeatability of an iPad application (Melbourne Rapid Field, MRF) in defining visual field defects found by Humphrey Visual Field (HVF) perimetry secondary to neuroophthalmic disease. Methods: Thirteen participants with visual field defects secondary to neuro-ophthalmic disease established with HVF SITA 24–2 were...
Article
Background Careful surgical management of traumatic wounds is important in open globe injury repair. This study examines the clinical outcomes following repair of open globe injuries with particular focus on wound-related issues.DesignRetrospective, cohort study of consecutive open globe injuries presenting to a tertiary referral eye hospital from...
Article
Importance Glaucoma is a significant health problem for which diagnosis remains suboptimal. Optic disc evaluation, which is fundamental to the diagnosis, is a difficult skill to acquire.Objectives To determine the optic disc characteristics that most influence decision making in the assessment of glaucoma likelihood and to ascertain the optic dis...
Article
To determine whether monoscopic versus stereoscopic viewing impacts on evaluation of optic disc photographs for glaucoma diagnosis in an expert population. Prospective observational study. Twenty pairs of high-quality monoscopic and stereoscopic photographs of similar size and magnification (i.e. forty images), were selected to demonstrate a range...
Article
Full-text available
Background: Eye screening programs have been effective in reducing the burden of eye diseases in the developing world. Most use paper recording systems which are prone to misplacement and are inefficient for auditing purposes. Digital data collection via mobile devices may prove more efficient, but reliable strategies information sharing between de...
Article
Following the recent demonstration of increased mitochondrial DNA mutations in lymphocytes of POAG patients, the authors sought to characterize mitochondrial function in a separate cohort of POAG. Using similar methodology to that previous applied to Leber's hereditary optic neuropathy (LHON) patients, maximal adenosine triphosphate (ATP) synthesis...
Article
Advancing age is a major risk factor for many neurodegenerative diseases but the underlying pathophysiology is not clear. We hypothesize that aging impairs the ability of neurons in the central nervous system to recover functionally after injury. To test this in retinal ganglion cells in vivo, we developed an optic nerve "stress test" which monitor...
Article
The similarities between glaucoma and mitochondrial optic neuropathies have driven a growing interest in exploring mitochondrial function in glaucoma. The specific loss of retinal ganglion cells is a common feature of mitochondrial diseases - not only the classic mitochondrial optic neuropathies of Leber's Hereditary Optic Neuropathy and Autosomal...
Article
Full-text available
The authors compared the visual gaze behaviors of glaucoma subspecialists with those of ophthalmology trainees during optic disc and retinal nerve fiber layer (RNFL) examination. Seven glaucoma subspecialists and 23 ophthalmology trainees participated in the project. Participants were shown eight glaucomatous optic disc images with varied morpholog...
Article
Full-text available
: Video-assisted thoracoscopic (VATS) thymectomy has been practiced in Australia for nearly two decades. Our aim was to assess the complete stable remission and asymptomatic disease rates after VATS thymectomy in nonthymomatous myasthenia gravis. There remains doubt that minimally invasive techniques achieve equal remission rates to open maximal op...
Article
Mouse models that accumulate high levels of mitochondrial DNA (mtDNA) mutations owing to impairments in mitochondrial polymerase γ (PolG) proofreading function have been shown to develop phenotypes consistent with accelerated aging. As increase in mtDNA mutations and aging are risk factors for neurodegenerative diseases, we sought to determine whet...
Article
Development of a standardized internet-based system to self-assess skills in optic disc examination for glaucoma risk assessment. Prospective internet-based observational study. Total of 197 participants (glaucoma subspecialists, general ophthalmologists and trainees) from 22 countries. Forty-two optic disc images demonstrating a range of features...
Article
Optic nerve morphology is affected by genetic and acquired disease. Glaucoma is the most common optic neuropathy; autosomal-dominant optic atrophy (ADOA) and Leber's hereditary optic neuropathy (LHON) are the most prevalent hereditary optic neuropathies. These 3 entities can exhibit similar topographical changes at the optic nerve head. Both ADOA a...
Article
To evaluate the association between demographical features, serum ALT and HBV DNA and the prevalence of significant fibrosis and inflammation on liver biopsy in patients with chronic hepatitis B. In this cross-sectional study of patients on St Vincent's Hospital HBV database, patients were classified into three groups on the basis of HBeAg status a...
Article
To prospectively evaluate the effect of 1.25 mg and 2.5 mg intracameral bevacizumab on surgical outcomes of trabeculectomy for neovascular glaucoma (NVG), with primary outcome measures being the regression of neovascularization of iris (NVI) and reduction of intraocular pressure (IOP). Consecutive patients with neovascular glaucoma from December 20...
Article
Full-text available
During physiological processes molecules undergo chemical changes involving reducing and oxidizing reactions. A molecule with an unpaired electron can combine with a molecule capable of donating an electron. The donation of an electron is termed as oxidation whereas the gaining of an electron is called reduction. Reduction and oxidation can render...
Article
Full-text available
To examine retinal function using the full-field electroretinogram (ERG) during and after acute intraocular pressure (IOP) elevation in wild-type mice. IOP was elevated by anterior chamber cannulation in wild-type C57/BL6 mice. The pressure-function relationship was determined by IOP elevation in steps from baseline to 80 mm Hg. The rate of functio...
Article
Glaucoma is increasingly recognized as a neurodegenerative disorder, characterized by the accelerated loss of retinal ganglion cells (RGCs) and their axons. Open angle glaucoma prevalence and incidence increase exponentially with increasing age, yet the pathophysiology underlying increasing age as a risk factor for glaucoma is not well understood....
Article
Full-text available
External hemipelvectomy is associated with high post operative morbidity and a poor functional outcome. We aim to explore a reconstruction technique to improve function and post operative appearance for patients who undergo external hemipelvectomy. We present a Case where extensive cancer involvement of pelvis and femur was managed with a novel sur...
Article
Objective Video-assisted thoracoscopic (VATS) thymectomy has been practiced in Australia for nearly two decades. Our aim was to assess the complete stable remission and asymptomatic disease rates after VATS thymectomy in nonthymomatous myasthenia gravis. There remains doubt that minimally invasive techniques achieve equal remission rates to open ma...