5th Annual Higher Degree Research Symposium

Ophthalmology & Vision Science

Friday 11 September 2020, 09:00am – 1:00pm

Please note that programme, content, faculty are subject to change without notice

TIME SPEAKER TOPIC PRIMARY SUPERVISOR

9:00 Arrival

9:05 Prof Peter McCluskey Opening Remarks and Acknowledgement of Country

9:16 Ms Stepanie Whiley Student Welfare Presentation

9:33 Dr Matthew Watson The clinical translation of artificial intelligence forscreening diabetic retinopathy in primary care Prof John Grigg

9:42 Dr Sophia ZagoraPaediatric uveitic glaucoma and the advent of biologic therapy Prof John Grigg

9:51 Ms Elissa Belluccini Characterisation of receptive fields in the mouse retina. Prof Paul Martin

10:00 Dr Adrian HuntTwelve-Month Outcomes of Ranibizumab vs. Aflibercept for Macular Oedema due to Branch Retinal Vein Occlusion: Data from the Fight Retinal Blindness! Registry.

Prof Mark Gillies

10:09 ~ 10min Break

10:20 Mr Dhimas Sakti MERTK retinopathy: understanding rate of visual loss in the therapeutic era Prof John Grigg

10:29 Mr Mohammad Nasir Uddin

Compelling structural evidence for lymphatics in posterior human optic nerve meninges Prof Paul Martin

10:38 Miss Rui ZhangSelective knockdown of hexokinase 2 in rods leads to age-related photoreceptor degeneration and retinal metabolic remodeling

Prof Mark Gillies

10:47 Dr Jed LusthausThe effects of open-angle glaucoma on conventional aqueous outflow, visualised by HaemoglobinVideo Imaging.

Prof Peter McCluskey

10:56 Dr Kelvin TeoDetrimental effects of delayed treatment for nAMD: Are fewer treatments the only cause of poor outcomes? –Data from the Fight Retinal Blindness! Registry

Prof Mark Gillies

11:05 Mr Dylan Kilpatrick Binocular vision and Teneurin-mediated development facilitates innate defensive behaviours in mice. A/Prof Matt Simunovic

11:14 Dr May May ChooAssessing agreement of clinical estimation of vertical optic disc cupping against RetCam assessment in the premature neonate and prospective observation for changes.

Prof John Grigg

11:23 ~ 10min Break

11:34 Ms Tayler Wishart Syndecan proteoglycans in mouse lens development Prof Frank Lovicu

11:43 Dr Jackie TanNovel infrared laser activated chitosan based thin film adhesive for sealing full thickness corneal laceration in rabbits.

Prof Stephanie Watson

11:52 Mr Charlie Song Development of a collagen-based bioink for wound healing and 3-D bioprinting Prof Gerard Sutton

12:01 Miss Pauline KhooSigns and symptoms of dry eye in Aromatase Inhibitor patients Prof Stephanie Watson

12:10 Mrs Nicole Hallet Deep learning based unsupervised and semi-supervised classification for Keratoconus Dr Jing Jing You

12:19 Ms Annette Hoskin Fireworks Related Eye Injuries Prof Stephanie Watson

12:28 Dr James Maberly Evaluating Severity of Microbial Keratosis Using Optical Coherence Tomography Prof Stephanie Watson

12:37 Dr Sammy Lee Career Pathways in Research

12:48 Prof John Grigg Closing Remarks

FRIDAY 11 September 2020

Professor John Grigg is Head of the Discipline of Ophthalmology atThe University of Sydney’s Save Sight Institute. He also consults atSydney Eye Hospital and The Children’s Hospital Westmead. With sub-specialties in glaucoma, cataract, paediatric and geneticophthalmology and clinical electrophysiology, Professor Griggcompleted his training at Sydney Eye Hospital and undertookfellowships in Australia and the UK. His research interests are geneticeye disease, glaucoma management and electrophysiology of thevisual system.

Professor Peter McCluskey is Chair of Ophthalmology atthe University of Sydney and Director of the Save Sight Institute. Heis an inflammatory eye disease specialist with more than 25 yearsexperience in the field. His primary clinical focus is vision threateningchronic inflammatory eye disease and he has a large clinical practiceas well as being actively involved in clinical research and clinicaltrials. His laboratory research focuses on mediators ofinflammatory eye disease. He has ongoing clinical andlaboratory collaborations in the United Kingdom, NewZealand, Vietnam and the United States. He is a passionate teacherwho regularly lectures and speaks at conferences internationally.

Dr Jingjing You is a Research Fellow at Save Sight Institute, Universityof Sydney and Co-Chair of Sydney Early and Mid Academic Network.Her research focuses on developing novel treatments for cornealdiseases. She was also appointed as a visiting academic fellow forSchool of Optometry and Vision Science at the University of NewSouth Wales, co-founded Australia Corneal Bioengineering WorkingGroup, served as a committee member of the ANZ Human Eye CellAtlas Consortium, and scientific advisor for NSW Tissue Bank, SouthEastern Sydney Local Health District.

Peter McCluskey Director, Save Sight Institute

John Grigg Head of Discipline

Jingjing You

PANELISTS

Dr Elisa Cornish a Staff Specialist at Sydney Eye & Westmead Hospital,a Senior Clinical Lecturer of the Faculty of Medicine, Studycoordinator for Ophthalmic Physiology & a member of the ExaminerBoard the Master of Medicine (Ophthalmic Sci), University of Sydney.She has completed two Clinical Fellowships at Sydney Eye Hospital:the Professorial (Uveitis) (2018) and Medical Retina (2019)Fellowships. As part of her Medical Retina training, she completed theISCEV electrophysiology training course and gained experience atMoorfields Eye Hospital in the Inherited Eye Disease and ClinicalGenetics department and Multimodal Imaging at Luigi Sacco Hospital,University of Milan, Italy.

Elisa Cornish

Dr. Yashar Seyed Razavi is a biomedical scientist who has recentlyreturned from a fellowship at Harvard Medical School - Schepens EyeResearch Institute, and Tufts Medical Center - Tufts University,performing basic and clinical research in ocular immunology and cellbiology. He has extensive experience working within academia andwith industry. His research includes the immune response in oculardisease models, including recent research into neuro-immunecrosstalk and the efficacy of therapeutic compounds on neuropathiccorneal pain (NCP). He is currently investigating retinal fibrosis withmembers of the Macula Research Group (MRG) at the Save SightInstitute.

Yashar Seyed Razavi

Dr Matthew Simunovic is an Associate Professor of Ophthalmology atthe University of Sydney and a Consultant Vitreoretinal Surgeon atSydney Eye Hospital and the Sydney Children’s Hospital’s Network.His research interests include novel treatments for retinal disease,optogenetic approaches to vision restoration, clinical trials ofgene therapy, approaches to subretinal drug delivery and and visualpsychophysics. He is currently supported by a Career DevelopmentAward from the Foundation Fighting Blindness, USA and has beenelected to the Macula Society.

Matthew Simunovic

Aims: 1. To examine the attitudes of General Practitioners (GPs) towards primary carediabetic retinopathy (DR) screening. 2. To evaluate an algorithm for detecting DR developedby the CSIRO.Methods: 1. A qualitative analysis of interviews with 15 GPs in Australia. 2. Non-mydriaticfundus photographs of LANDMark study participants, with and without diabetes, graded by aretinal specialist and compared with the CSIRO algorithm.Results: 1. GPs are considered ‘gate-keepers’ for chronic disease, but lack of expertise,appropriate equipment, time and adequate financial incentives lessen participation in DRscreening. 2. In detecting referable DR the algorithm sensitivity was 43.7% and specificity94.6%. After algorithm retraining its sensitivity was 84.6% and specificity 88.8%.Conclusion: For primary care DR screening to be effective, policy makers must considerfurther the barriers and incentives. The ‘black box’ of AI, construction of reference standardsand inter- and intra-grader variability are key determinants of AI performance in DRscreening.

Dr Matthew WatsonThe clinical translation of artificial intelligence for screening diabetic retinopathy in primary care

ABSTRACTS

Dr Sophia ZagoraPaediatric uveitic glaucoma and the advent of biologic therapy.

Background: The mainstay of uveitis treatment is steroids. Steroid induced glaucoma is welldocumented and has been found to account for a quarter of all acquired glaucoma inchildren. Steroid sparing immunosuppressive agents including biologics are increasingly used.Aims: To highlight the difficulties in managing uveitic glaucoma in children andto investigate whether there has been i) a decrease in uveitic glaucoma ii) decrease inglaucoma surgery and iii) increase in success of glaucoma surgery based on visual acuity andlowered IOP with the treatment of biologics and more aggressive steroid sparingimmunosuppression for uveitis in children.Hypothesis: The increased use of biologics and other steroid sparing agents versus steroids,have reduced the need for glaucoma surgery and increased success of glaucoma surgery inchildren with uveitis.Methods: Literature review and a retrospective chart review of all paediatric uveitis patientspresenting to the Children’ s Hospital Westmead and Sydney Eye Hospital, NSW from 2005-2020.

Visual processing begins in the retina, where patterns of electrical activity in ganglion cells(GCs) represent different features of the visual world. These features are encoded by GCreceptive fields (RF), which have traditionally been studied using spots, bars, gratingsand spatiotemporal white-noise stimuli. A more recent technique uses flashing bars and theinverse Radon transform to reconstruct RFs. This approach is rapid, parallelizable, separatesON and OFF components, and captures RFs with non-linear properties (Johnston et al.,2014). Recent work in our laboratory (unpublished, Eiber et al.) has applied this techniqueusing flashing bars (‘Radon stimulus’) and iterative tomographic reconstruction. We performin vitro whole-cell patch clamp recordings of GCs in the mouse retina, as the Radon stimulusis presented. This presentation will compare RF maps generated from subthreshold and spikeresponses, and demonstrate the correlation between RF structure and cell morphology.

Ms Elissa BellucciniCharacterisation of receptive fields in the mouse retina

Dr Adrian HuntBinocular vision and Teneurin-mediated development facilitates innate defensive behaviours in mice.

Purpose: To compare the visual acuity (VA) outcomes of ranibizumab vs. aflibercept in thetreatment of cystoid macular oedema due to branch retinal vein occlusion in routine clinicalpractice.Participants: Treatment-naïve eyes with branch retinal vein occlusion.Methods: Generalised additive mixed linear models were used to compare agents.Results: We identified 285 treatment-naïve eyes receiving ranibizumab or aflibercept.Aflibercept was more effective at reducing macular thickness than ranibizumab (-170μm vs. -140 μm (P <0.001)). Switching was more common from ranibizumab (15%) than fromaflibercept (7%; P = 0.02).Conclusions: Visual acuity outcomes at 12 months in the treatment of BRVO withranibizumab and aflibercept did not differ, despite a greater effect on macular thickness withaflibercept.

MERTK is expressed in the retinal pigment epithelium (RPE) mutated in a rare groupof retinitis pigmentosa (RP) patients. Understanding the rate of visual loss will guide theoptimum time for therapeutic intervention. Patients data from baseline (BL) and last follow-up (LFU) were included. Best corrected visual acuity (BCVA), spectral domain-opticalcoherence tomography parameters including central macular thickness (CMT) and ellipsoidzone (EZ), ultra-widefield fundus autofluorescence were analyzed. Five patients with meanage at BL of 20.9 years old (14.4-42.3) and mean follow up of 51.4 months (22.3-61.1months) were included. Decline rate from BL to LFU of BCVA (10 eyes), CMT (10 eyes), andEZ (8 eyes) were 0.07 LogMAR/year, 1.70µm/year, 137.01µm/year respectively. This cohortshowed early visual loss, moderately rapid EZ line reduction and macularhyper autofluorescence. The relative rapid decline in these biomarkers suggests a narrowtimespan for intervention.

Mr Dhimas Hari SaktiMERTK retinopathy: understanding rate of visual loss in the therapeutic era

Mr Mohammed Nasir UddinCompelling structural evidence for lymphatics in posteriorhuman optic nerve meninges

Lymphatics play an important role in fluid homeostasis & immune surveillance. With ourearlier demonstration of lymphatics in the choroid, this study aims toprovide the evidence of optic nerve lymphatics including their precise location. Optic nervefrom 12 human adult eyes were examined in thisstudy. Ultrastructural characterization & immunohistochemistry (IHC) was carriedout using D2-40, LYVE-1 (Lymphatic); UEA Lectin (blood vessel) markers. IHC showed D2-40+/UEA Lectin- and LYVE-1+/UEA Lectin- lymphatic capillaries in retrolaminar optic nervemeninges. Ultrastructural features of lymphatics demonstrated presence of the anchoringfilaments, luminal flocculent protein but absence of erythrocytes, basal lamina, Weibel-Palade bodies & fenestrae. Lymphatics were precisely located within the arachnoid materadjacent to sub-arachnoid space (SAS) in close association with meningothelialcells (MEC). This study suggests that MEC and arachnoid lymphatics form the structural basisfor functional interaction between lymphatics and cerebrospinal fluid (CSF) in healthy centralnervous system (CNS).

Hexokinase 2, the first rate-limiting enzyme in glycolysis, catalyzes the phosphorylation ofglucose and regulate metabolism of the retina. We crossed rhodopsin-Cre mice withhexokinase 2 (HK2)-floxed mice to study the effect of knocking down HK2, the first rate-limiting enzyme in glycolysis, on retinal health and metabolic remodeling. We found thatknocking down HK2 in rods led to age-related photoreceptor degeneration, evidenced byreduced expression of photoreceptor-specific proteins, age-related reductions of the retinaand impaired electroretinographic responses. This might be related to metabolic remodelingcaused by loss of HK2, which is evidenced by upregulation of HK1, phosphorylation ofpyruvate kinase muscle isozyme 2. Mass spectrometry found that deletion of HK2 in rodsresulted in accumulation of 13C-glucose along with decreased pyruvate and increasedmetabolites in the TCA cycle. Our data suggest that HK2-mediated aerobic glycolysis in rods isdispensable for the maintenance of photoreceptor structure and function and that long-terminhibition of aerobic glycolysis leads to photoreceptor degeneration.

Miss Rui ZhangSelective knockdown of hexokinase 2 in rods leads to age-related photoreceptor degeneration and retinal metabolic remodeling

Mr Dylan KilpatrickBinocular vision and Teneurin-mediated development facilitates innate defensive behaviours in mice.

Mice continue to be a popular model for investigating mammalian vision and visually-mediated behaviour. Adding to their behavioural repertoire, mice possessunlearned defensive strategies when presented with “looming” visual threats. Mimicking anaerial predator, responses to these visual threats are biased towards presentation withinthe dorsal, binocular portion of their visual field. However, the role of binocular vision hasnot been directly assessed. Using a “looming” behavioural paradigm, we investigated therole of binocular vision and utilised Teneurin gene family null mutants. We have foundthat binocular vision is important in facilitating defensive behavioural responsesand that retinofugal miswiring caused by Teneurin gene knockouts diminishes or modulatesthese responses. This work continues to better characterise these unlearnedmurine behaviours as well as elucidate the importance of the Teneurin gene family in visualdevelopment and function. Future work is focused on adapting this behavioural paradigm toevaluate vision restoration in models of inherited blindness.

Dr Kelvin TeoDetrimental effects of delayed treatment for nAMD: Are fewer treatments the only cause of poor outcomes? –Data from the Fight Retinal Blindness! Registry

Dr Jed LusthausThe effects of open-angle glaucoma on conventional aqueous outflow, visualised by Haemoglobin Video Imaging.

Background: Intraocular pressure (IOP) reduction is the foundation of glaucoma treatment,but no clear understanding of IOP regulation exists. Visualisation of physiological aqueousoutflow (AO) into the episcleral venous system (EVS) is now possible with HaemoglobinVideo Imaging (HVI).Preliminary data: Early results suggest a significant reduction of AO in glaucomatouseyes. Variations in AO recovery occurred after trabecular bypass surgery and may representhomeostatic reorganisation.Hypothesis: Regulatory mechanisms within the EVS contribute to IOP control and becomedysfunctional in open-angle glaucoma.Aims: To identify evidence of regulatory mechanisms within the AO system that maycontribute to IOP homeostasis. The secondary aim is to detect differences in EVS capacitancebetween patients with and without glaucoma.Methods: Prospective studies of controls and glaucomatous eyes. Responses to dynamicmanipulations, Valsalva Manoeuvre and water-drinking test, will be recorded with HVI andquantified using Image J software.Anticipated outcomes: Identifying differences in AO responses to interventions in this thesismay improve understanding of IOP control and dysregulation in glaucoma.

The burden of treatment, if strictly adherent to monthly regimen, is high for vascularendothelial growth factor inhibitors for neovascular age related macular degeneration(nAMD). New treatment strategies like treat and extend have been devised and proven to asefficacious as monthly treatments while mitigating the high frequency oftreatments. Despite this, many patients in real world clinical practice still face difficultieswith adherence to such strategies. This results in a general under treatment which hasbeen shown to adversely affect visual outcomes. While fewer number of treatments havebeen shown in many real world studies to be associated with poorer outcomes, wehypothesize that appropriately timed treatments is also important for optimal outcomes.In this study we aim to use real world evidence from the fight retinal blindness (FRB!) registryto assess the detrimental effects of delayed treatment in active disease on visual outcomesin nAMD. These findings can potentially inform the optimal treatment for these patients inclinical settings.

Dr May May ChooAssessing agreement of clinical estimation of vertical optic disc cupping against RetCam assessment in the premature neonate and prospective observation for changes.

Ms Tayler WishartSyndecan proteoglycans in mouse lens development

Syndecans are heparan sulfate proteoglycans (HSPGs) comprised of a core protein decoratedwith sulfated heparan sulfate glycosaminoglycan chains. Given their essential rolesas regulators of cellular interactions, here we compare the spatiotemporal immunolabellingof syndecans (1-4) in the developing murine lens. We found that Syndecans -2, -3 and -4 butnot -1 are present in the developing lens, each displaying differences in their spatial andtemporal expression patterns: Syndecan-2 was localised to the lens capsule, nucleiof epithelial cells in the germinative zone and in the differentiating fibre cells. Syndecan-4 was strongly expressed in the newly differentiating fibre cell tips, and diffusely throughoutthe lens epithelium, while syndecan-3 was limited to maturing fibre cells. The differentialspatial and temporal expression of syndecan core proteins suggests that lens cells acquire adistinctive repertoire of HSPGs as they differentiate, resulting in selective patterns ofHSPG interactions and activity, hence differential roles for these HSPGs at key stages oflens development.

Introduction: To assess agreement between binocular assessment of optic disc cup-disc-ratio and objective RetCam evaluation in premature infants. To look at changes during periodof retinal maturation.Methods: Vertical optic disc ratio(vCDR) by indirect ophthalmoscopy(28D lens) werecompared with RetCam images calculated-average values. Examinations were taken atTimepoint 1(31-36w) and 2(37-40w). Consistency between methods was assessed withintraclass correlation coefficient(ICC). Bland-Altmann plots were used for agreementanalysis.Results: In total, 504 images were captured. Of 126 eyes examined, average vCDR byclinician was 0.30(SD:0.1) and by RetCam 0.32(SD:0.1). ICC values showed moderatecorrelation. Bland-Altman plot showed wide 95% limits of agreement(-0.24, 0.26). Paired t-test showed significant change in vCDR between the timepoints for infants with birthweight<1000grams (p=0.001).Conclusion: Clinical estimation and RetCam findings though not interchangeable, eachmethod captured similar vCDR change over time. Mean vCDR in this population was 0.3.Birthweight <1000g show variation of vCDR over time.

Dr Jackie TanNovel infrared laser activated chitosan based thin film adhesive for sealing full thickness corneal laceration in rabbits.

Mr Charlie SongDevelopment of a collagen-based bioink for wound healing and 3-D bioprinting

A collagen-based bioink which can be applied directly into the corneal wound by a hand-helddevice to seal the wound and promote healing is under development in thisproject. The collagen ink showed good printability and transparency in previousexperiments. Ex-vivo experiment to access the wound-sealing ability of the collagenink showed that crosslinked collagen ink can seal a 1 mm perforation and hold upto a pressure of 22 mm Hg. Corneal stromal cells encapsulated inside the collagen inkshowed good viability and ability to proliferate after crosslinking, which indicates thepotential of the collagen ink as a cell-carrier in 3-D bioprinting. In conclusion, the collagenink can potentially be used as a filler/glue in corneal wound treatment and a cell-loaded inkin 3-D bioprinting.

Aim: To compare burst pressures of penetrating corneal incisions repaired using anovel laser-activated chitosan patch against self-seal or sutures.Methods: Central corneal penetrating incisions (2mm) were created on the right eye of135 albino rabbits. Incisions were closed using the chitosan adhesive, 10-0 nylon suturesor left to self-seal, (n=45 each). At timepoints up to 14 days post-operatively, 5 rabbitsfrom each group were euthanized and their corneoscleral rim dissected for burstpressure testing using a modified Barron chamber.Results: Burst pressures from the chitosan patch were persistently higher than boththe suture or self-sealed groups from 0 to 72hrs (p<0.05), with 207, 11 and 13 mmHg after3 hours respectively. Burst pressures between all groups did not show statisticaldifference after 7 or 14 days.Conclusion: This adhesive technology can seal full thickness corneal incisions, toleratehigh burst pressures and accelerate healing.

Miss Pauline KhooSigns and symptoms of dry eye in aromatase Inhibitor patients

Mrs Nicole HalletDeep learning based unsupervised and semi-supervised classification for Keratoconus

Keratoconus is a multifactorial, progressive, degenerative corneal disease with significantdifferentiation in progression rates across patients. One of the greatest challenges forclinicians is the evaluation of risk progression for each patient, as there is currently nobroadly accepted disease classification or progression model. We are developing andtesting deep learning models to support clinical decision making and improve patientoutcomes. Utilising a retrospective data set of 124 Keratoconus and 30 control patientswe have developed a fully connected deep neural network. This model is a supervisedmulti-layer perceptron model to establish disease diagnosis and an unsupervised Bayesianneural network – comprised of a Variational autoencoder and a Gaussian mixture model -for disease classification To date with our model we have been able to cluster ourpatients against the Amsler-Krumeich classification with an accuracy of 82%. We arecurrently working to optimise variable selection and improve clustering accuracy.

Women with breast cancer treated with aromatase inhibitor (AI) therapy can suffer withdry eye (DE) symptoms. The signs of DE in this group have not been established. The aimof the study was to test the hypothesis that DE symptoms in AI therapy are associatedwith signs of DE. A cross-sectional, observational study of postmenopausal womentreated with AI was conducted. Ocular and treatment symptoms were assessed usingquestionnaires, and DE clinical assessments were performed.The study included 25 women on AI therapy with a mean age of 62years. 64% reported of symptoms of DE. Higher tear osmolarity (p=0.002) and increasedmeibomian gland dropout (p=0.002) were observed in symptomatic DE patients comparedto asymptomatic AI patients.The likelihood of a patient experiencing DE symptoms increases with longer duration of AIuse. Meibomian gland dropout can aid clinicians in identifying women on AI therapy atrisk of developing DE and allow treatment to be targeted.

A cross-sectional observational study including tertiary eye care hospitals in 5 countries andprivate ophthalmology practices in the Netherlands was conducted. We used an on-lineplatform to collect data on the occurrence of and associated factors with severe vision lossfrom fireworks-related ocular trauma during celebrations, including festivals. Demographicand clinical data for patients affected were analyzed and statistical significance wasassessed. Of 388 patients, 71 (18.3%) had severe vision loss (worse than 6/60) due tofireworks-related ocular trauma at 4 week follow-up. Mean age was 20.6 years (range 2 to83 years) and a male predominance of 4:1. Fireworks-related ocular trauma resultedin severe vision loss with factors including penetrating injury and lens injury associated withan increased risk of severe visual loss.

Ms Annette Clayfield-HoskinFireworks Related Eye Injuries

Dr James MaberlyEvaluating Severity of Microbial Keratosis Using Optical Coherence Tomography

Methods: This prospective study included 68 eyes of suspected infective keratitis from2016 to 2018. Corneal structure parameters were evaluated by image analysis of cornealOCT data. These characteristics were used to place each case in a severity group based ona point system. The hypothesis is that the higher severity cases based on OCT imagescoring would predict poor response to antibiotic therapy and those patients requiringsurgical intervention.Results: The average score was 10 out of 28 points with a standard deviation of (+/- )6points. There was no significant difference between the scores of the different strains ofmicrobes. The patients who required surgery had a significantly higher score than thosethat reached resolution without intervention (p= 0.042).Conclusion: This study demonstrated that characteristics evident on AS-OCT analysiscorrelates with the need for surgical intervention.

Thank you for attending the 5th Annual HDR Student

Syposium.The Symposium organising committee:

Pauline Khoo

Janet Bunn Emma Coleman

Maria Cabrera Aguas Morgan Kailin Overmass