UBC Department of Ophthalmology and Visual Sciences 31st
UBC Department of Ophthalmology and Visual Sciences 31st Annual Research Day VGH/UBC Eye Care Centre Friday April 24, 2015 UBC Ophthalmology and Visual Sciences Speakers “Clinically relevant basic science and clinical research” Special Guest Speaker Jacque Duncan, MD Professor of Clinical Ophthalmology University of California, San Francisco “High resolution retinal imaging: new outcome measures for clinical trials in Retinitis Pigmentosa” This event is an Accredited Group Learning Activity (Section 1) as defined by the Maintenance of Certification program of the Royal College of Physicians and Surgeons of Canada. This program has been reviewed and approved by UBC Division of Continuing Professional Development. Video conferencing will be available. This program lists the proposed presenters and discussants at the time of printing and is subject to change. THE UNIVERSITY OF BRITISH COLUMBIA Dept of Ophthalmology and Visual Sciences Faculty of Medicine 2550 Willow Street Vancouver, B.C. Canada V5Z 3N9 Tel: (604) 875-4555 Fax: (604) 875-4663 April 15, 2015 Dear Colleagues: It gives me great pleasure to welcome you to the 31st Annual UBC Department of Ophthalmology and Visual Sciences Research Day. The program promises to be a stimulating blend of clinical and basic science projects that will highlight the excellent work that has been conducted over the past year in our Department. I am pleased to welcome Dr. Jacque Duncan as our invited guest. Dr. Duncan comes to us from the University of California, San Francisco, where she is Clinical Professor of Ophthalmology and Director of the Retinal Degenerations Clinic and Retinal Electrophysiology Laboratory. Her background includes residency training at the University of California, San Francisco and a medical retina fellowship at the Scheie Eye Institute at the University of Pennsylvania, where she focused on patients with age-related macular degeneration and inherited retinal degeneration. Her expertise includes the diagnosis and treatment of retinal diseases such as Usher syndrome, cone-rod dystrophy and Stargardt disease. Over the past 9 years Dr. Duncan has worked closely in collaboration with Austin Roorda, PhD, to use adaptive optics scanning laser ophthalmoscopy (AOSLO) to characterize cone structure non-invasively in living eyes of patients with a variety of retinal diseases. They have developed improved strategies to quantify cone photoreceptor integrity in normal eyes and eyes with inherited retinal degeneration. Dr. Duncan has served as the Clinic Director for five multicenter clinical trials at UCSF, including the National Eye Institute-sponsored Longitudinal Studies of the Ocular Complications of AIDS (LSOCA) study. Dr. Duncan is also the site PI on an NEI-funded Bioengineering Research Partnership grant to Study Visual Function on a Cellular Scale using AOSLO. I would like to thank this year’s organizing committee, Dr. Orson Moritz, Dr. Ipek Oruc, Dr. Simon Warner, Dr. Paul Mackenzie, and Dr. Zaid Mammo for their efforts in coordinating today’s meeting. This is a very significant contribution to the academic mandate of our Department. A sincere thank you to this year’s meeting sponsors who have generously provided unrestricted educational grants. Platinum – Alcon Canada Inc, and Bayer Inc., Gold – Allergan Inc and AMO (Canada), Bronze – Novartis Inc, and Pfizer Canada Inc. David Maberley, MD, FRSC Professor and Head Department of Ophthalmology and Visual Sciences, UBC Head, Department of Ophthalmology Vancouver Acute Regional Department Head, Department of Ophthalmology, VCH and PHC Program 8:00 am Opening Remarks – video conferencing starts……………………………………..………D. Maberley Session 1 – Retinal Disease Mechanisms Moderator: A. Joe 8:05 Novel molecular approach for long term survival of transplanted photoreceptor precursor cells.......................................................................................................................................A. Yanai 8:13 Visual and anatomic outcomes of intravitreal dexamethasone for cystoid macular edema in retinal vascular occlusion and diabetic retinopathy ………………..…………………………………….S. Teja 8:21 Suppression of membrane attack complex reduces inflammasome activation in the rodent eye……………………….…………………………………………………………………………...T. Zhao 8:29 Drusen component amyloid beta promotes membrane attack complex formation on ARPE19…………………………………………………………………………………………..…………. S. Cao 8:37 Inducible ex vivo gene therapy for the treatment of X-linked retinoschisis……………...…E. Bashar 8:45 Evaluating the anti-inflammatory effect of a dietary compound in a model of dry age-related macular degeneration.………….............................................................................................R.T. Liu 8:53 Lamellar hole epiretinal proliferation……………………………..…………………………....…C. Pang 9:01 Discussion…………………………………………………………………………E. Navajas and D. Bhui 9:17 Introduction of Dr. Duncan………………………………………………………………………O. Moritz 9:20 GUEST SPEAKER – High resolution retinal imaging: new outcome measures for clinical trials in Retinitis Pigmentosa…………………………………………………………........…………….J. Duncan 10:05 Discussion………………………………………………………………………………………..……...TBA 10:20 Coffee Break Session 2 – Glaucoma and Cornea Moderator: S. Warner 10:45 Fibro/adipogenic progenitors and thyroid eye disease...…………………….............................A. Joe 10:53 Stop smoking: breathe easier, live longer and … get glaucoma?………………………….R. Symes 11:01 Erectile dysfunction in patients with glaucoma…………………………………………………...G. Law 11:09 Anterior segment OCT measurements predictive of IOP lowering after cataract surgery……………………………………………………………………………………………....B. Eadie 11:17 Corneal cross-linking in pediatric patients with progressive keratoconus…………………….S. Wise 11:25 Graft free Ahmed valve implantation through a 6 mm scleral tunnel…………………………K. Jiang 11:33 Intraocular lens power calculation formulas for flat corneas…………………………………...C. Chen 11:41 Discussion…………………………………………………………………P. Saunders and K. Mohaseb 11:57 Lunch – Medical Student & Alumni Centre, 2750 Heather Street Session 3 – New Tools & Procedures Moderator: O. Moritz 1:00 A survey of community family physicians about ophthalmic knowledge………………..H. O’Donnell 1:08 Big data visualizations in ophthalmology. …………………...…………………………………….A. Lee 1:16 The slit lamp proptometer: a novel digital slit lamp exophthalmometer ……..……………...Y. Chung 1:24 Subthreshold diode microPulse photocoagulation for persistent subretinal fluid following maculaoff retinal detachment surgery: three case reports...…………………….….………………….H. Johal 1:32 Test characteristics of point of care ultrasound in the emergency department for the diagnosis of retinal detachment.………………………………………………………………………………....B. Silver 1:40 Quantitative non-invasive angiography of the fovea centralis using speckle variance optical coherence tomography.……………………………….........................................................Z. Mammo 1:48 Discussion………………………………………………………………………..A. Giligson and A. Butler Session 4 – New Disease Models Moderator: S. Warner 2:02 Animal model of dry AMD induced by chronic exposure to a drusen component……………W. Gao 2:10 Rapid high yield production of knockout Xenopus laevis using CRISPR/Cas9.…………..J. Feehan 2:18 Timeline of asymmetrical and symmetrical motor neuron loss in an animal model of amyotrophic lateral sclerosis…………………………………………………………………………………...J. Morrice 2:26 Transplantation of genetically engineered mesenchymal stem cells (MSCs) to reverse anterior segment eye defects in Aniridia causing Glaucoma and subsequent blindness.….V. Nizamudheen 2:34 Identifying the ‘‘driver’’ genes for multi-systemic 2p15-16.1 microdeletion syndrome using in vivo zebrafish assays.…..…………………………………………………………………………….H. Bagheri 2:42 Discussion…………………………………………………………..………………….R. Cottle and V. Yin Session 5 – Pediatric & Neuroophthalmology Moderator: O. Moritz 2.54 Pediatric infectious keratitis at tertiary referral centers in Vancouver, British Columbia……................................................................................................................G. Noureddin 3:02 The effects of hemianopia on experimental studies of alexia...………...............................C. Rubino 3:10 Current patching protocols for amblyopic patients among currently practicing strabismus specialist ..…………………………………………………..……………………………………….R. Rewi 3:18 Global motion perception deficits in amblyopia.……………………………...………………....K. Meier 3:26 Voice processing in developmental prosopagnosia.……………………………...……………….R. Liu 3:34 Pre-operative prism adaptation testing: selection criteria and its long term efficacy in acquired esotropic patients.………………………………………………………………………D. Jeyatheswaran 3:34 Discussion……………………………………………………………………..M. Rees and M. Aroichane 3:55 Closing Remarks – video conferencing ends………………………………....……………..O. Moritz 3:55 Judging 4:00 Reception & Announcement of Awards Abstracts Session 1 – Retinal Disease Mechanisms Moderator: A. Joe Novel molecular approach for long term survival of transplanted photoreceptor precursor cells Anat Yanai, Christopher Laver, Emran Bashar, and Kevin Gregory-Evans Purpose: Transplantation of photoreceptor precursor cells (PPCs) derived from human embryonic stem cells (hESCs) is a promising and widely applicable approach for the treatment of retinal degenerations. However, the percentage of PPCs that undergo functional integration remains low (~3.5%). We developed an ex-vivo system to facilitate optimization of PPC transplantation and will focus on determining the factors that enhance PPC survival and integration. Methods: We compared the survival rate of untreated PPCs to PPCs pre-treated with a novel glycopeptide (AAGP™) in our ex-vivo retinal explant system. The system includes rat neural retina placed on top of hESCderived retinal pigment epithelium (RPE). PPCs were inserted between the neural explant and underlying RPE, mimicking subretinal transplantation, and their survival was assessed 10 days post-transplantation by flow cytometry. We also examined explant microstructure and survival in AAGP-treated explants when no PPCs are present. Results: The survival rate of PPCs pre-treated with AAGP™ was 3 fold higher than untreated PPCs 10 days post-transplantation. AAGP treatment of the explant alone resulted in no improvement in tissue microstructure or survival, indicating that the protective effect of AAGP was directly on the PPCs. We are presently identifying the mechanism underlying the protective effect of AAGP. Conclusions: A model system that includes retinal explants, co-cultured with hESC-derived RPE, can be used to screen and define factors that enhance the viability of transplanted PPCs and increase their ultimate integration to the degenerating retina. Identifying factors, such as AAGP, that enhance viability and integration of PPCs into retinal explants in an ex-vivo system can then be validated in in-vivo models of retinal degeneration. Visual and anatomic outcomes of intravitreal dexamethasone for cystoid macular edema in retinal vascular occlusion and diabetic retinopathy Salina Teja, Aaron Lee, David Maberley, and Patrick Ma Purpose: Clinical trials have shown that anti-VEGF therapy has a primary role in the treatment of cystoid macular edema (CME). There are many patients that become recalcitrant to this over time and concurrent intravitreal steroid has been shown to reduce this tachyphylaxis. Our purpose is to quantitatively assess the visual and anatomic outcomes of the Ozurdex implant for CME in retinal vascular occlusion (RVO) and diabetic retinopathy (DR). Methods: This is a retrospective chart review of 80 consecutive patients who were diagnosed with anti-VEGF refractory macular edema secondary to a retinal vascular occlusion or diabetic retinopathy and treated with intravitreal dexamethasone. Patients were stratified into 2 groups according to treatment indication for the Ozurdex implant, and excluded if there was evidence of macular ischemia on fluorescein angiogram. Data was collected from up to 1 year prior to injection to up to 2 years post-injection and included visual acuity, intraocular pressure, central macular thickness, number of anti-VEGF injections, cost of treatment, and side effects (cataract surgery, intraocular pressure rise requiring treatment). Results: 80 Patients met inclusion criteria. Results are pending. Conclusions: Studies have shown that the slow-release Ozurdex implant has been effective in reducing the number of anti-VEGF injections required while achieving superior anatomic outcomes in the management of CME in RVO and DR. Our study hopes to further quantify these findings by including all patients eligible for treatment in a real clinic setting. Suppression of membrane attack complex reduces inflammasome activation in the rodent eye Si Xi (Tom) Zhao, Jiangyuan Gao, Jenifer Van1, Jing Z.Cui, Eleanor To; Aikun Wang, Sijia Cao, Patrick L. McGeer2, Joanne A. Matsubara 1 Pacific University College of Optometry, Forest Grove, OR, United States Kinsmen Lab of Neurological Research, University of British Columbia, Vancouver, BC, Canada. 2 Purpose: The membrane attack complex (MAC) is a key player in the pathogenesis of age-related macular degeneration (AMD) and is a putative activator of the NLRP3 inflammasome. Aβ, a component of drusen, is also a candidate activator of the inflammasome. However, the interactions of MAC and Aβ are poorly understood. The purpose of this study is to identify the effects associated with MAC and inflammasome activation in the outer retina and to evaluate the therapeutic merits of MAC suppression. Methods: Adult Long-Evans rats were divided into treatment and control groups. Treatment groups received oral aurin tricarboxylic acid complex (ATAC) in drinking water and control groups receiving drinking water alone (no ATAC). Groups were sacrificed at 7.5 or 11.5 months, after approximately 40 days of ATAC treatment. To study age-related changes of Aβ and MAC in outer retina, naive animals were sacrificed at 2.5, 7.5, and 11.5-months of age. Eye tissues underwent immunohistochemistry and western blot analysis for MAC, Aβ, NF-κB activation, as well as cleaved caspase-1 and interleukin-18 (IL18), an indicator and mature product of inflammasome activation, respectively. Vitreal samples were collected and assessed by multiplex assays for secreted levels of IL18 and IL1β. Results: Immunohisochemistry and Western blot analysis demonstrated an age-dependent increase in MAC, Aβ and NF-κB activation in the outer retina. Systemic ATAC resulted in a prominent reduction in MAC formation in outer retina and a concomitant reduction in inflammasome activation measured by cleaved caspase-1 and secreted levels of IL18 and IL1β. Systemic ATAC did not affect NF-κB activation in RPE cells. Conclusions: A naturally occurring, age-related build-up of MAC and Aβ was observed in rat outer retina, and is consistent with observations from postmortem human eyes. Systemic treatment with ATAC in rodents resulted in a prominent reduction of MAC deposition and a subsequent decrease in NLRP3 inflammasome activation. Our results suggest that targeting MAC with ATAC may be a method to suppress NLRP3 inflammasome activation and thereby reduce levels of IL1β and IL18 in ocular tissues. Drusen component amyloid beta promotes membrane attack complex formation on ARPE-19 Sijia Cao, Jiangyuan Gao, Aikun Wang, Jing Z. Cui, Joanne A. Matsubara Purpose: Drusen are hallmark deposits associated with age-related macular degeneration (AMD) and amyloid beta (Aβ) and membrane attack complex (MAC) have been both reported in drusen. However, the relationship between Aβ and complement activation on RPE cells is not yet known. In this study we test the hypothesis that Aβ promotes MAC formation on RPE cells by stimulating RPE cells with Aβ in the presence of normal human serum (NHS) as a source of complement proteins. To further understand the effect of Aβ on the regulation of complement cascade, several complement regulators were also measured. Methods: ARPE-19 cells were stimulated with fibrillar Aβ in the presence of NHS (25%) or heat-inactivated (HI)-NHS for 24 hours. Positive controls included stimulation with zymosan and NHS. Negative controls included Aβ or serum-free medium alone. Next, ARPE-19 cells were fixed and immunostained for MAC (1:50, Clone aE11, Dako) and the nuclei were counterstained by DAPI. The MAC formation was quantified as the percentage of MAC immunoreactive cells over the total number of cells per 40× field. The gene and protein expressions of complement regulators were measured by quantitative PCR and western blot (WB) in cells treated with Aβ or controls. Results: The level of MAC immunoreactive cells was higher in the ARPE-19 treated with NHS and Aβ compared to its corresponding negative control (mean ± standard error of mean (SEM), 14.9±1.2% versus 0.4±0.2%, n=6, p < 0.01, Student’s t test). The complement regulator CD55 was downregulated by Aβ by 20 folds (p < 0.05, Student’s t test), while CD46, CD59, CFH and CFI did not change. The protein level of CD55, as measured by WB, showed a decreased trend after 6-hour treatment with Aβ. Conclusions: The drusen component, Aβ, induced MAC formation on ARPE-19 cells, and it may promote this process by downregulating the expression of the complement regulator CD55. It is known that the Y402H at-risk variant in the CFH gene is associated with greater MAC deposition in choroid compared to the protective variant. Thus, a concomitant exposure to drusen components, such as Aβ, may further exacerbate MAC formation leading to RPE dysfunction in outer retina. Inducible ex vivo gene therapy provides enhanced neuroprotection in X-linked retinoschisis mouse model. Emran Bashar, Andrew Metcalfe, and Kevin Gregory-Evans Purpose: X-linked retinoschisis (XLRS) is a juvenile-onset macular degeneration caused by haploinsufficiency of a cell adhesion protein retinoschisin (RS1), secreted by photoreceptors and bipolar cells. RS1 mutations can lead to secretion of non-functional proteins, thus, as loss-of-function mutations are more amenable to gene therapy, XLRS is an excellent candidate for ex vivo gene therapy. Here, we report the structural and functional benefits observed after intravitreous delivery of MSCs genetically modified to secrete retinoschisin in response to topical doxycycline (Dox) in the retina of our XLRS mouse model. Methods: MSCs were harvested from syngeneic RS1KO mouse adipose tissue and transfected via electroporation with a plasmid containing Tet transactivator (tTA) under CMV promoter and a second plasmid with human RS1 cDNA under Tet response element (TRE). Transfected cells were selected using geneticin and hygromycin for two weeks and then assayed by ELISA for retinoschisin synthesis. 100,000 genetically modified MSCs were injected into the vitreous cavity of the RS1KO mice at the age of post natal day 21. 50 ul of topical Dox (5 mg/ml) was administered daily on the treated eye. The control groups received either unmodified MSCs or sham injection. Electroretinogram (ERG), optokinetic tracking response (OKT) and histology data were recorded for all cohorts at 2, 4 and 8 weeks post injection time points. Results: Enhanced neuroprotection and inner nuclear layer tissue integrity were observed in retinas which received modified MSCs injection compare to the sham injection at all three time points. Lower b/a wave ratio in dark-adapted maximal ERG response and increased spatial frequency thresholds in OKT highlighted improvement in preserving vision in this group compared to others. These functional benefits were correlated with increased structural preservation of the inner nuclear layer. Conclusion: Intravitreal delivery of genetically modified MSCs secreting retinoschisin in response to topical Dox showed promising results in the XLRS mouse model. This inducible approach provides more control over the target gene expression in vivo thus ensures more safety and efficacy. Evaluating the anti-inflammatory effect of a dietary compound in a model of dry age-related macular degeneration R. Tom Liu, Aikun Wang, Eleanor To, Jiangyuan Gao, Sijia Cao, Jing Cui, and Joanne Matsubara Purpose: Chronic inflammation is a key pathogenic process in age-related macular degeneration (AMD). We, and others, have studied the role of drusen in promoting pro-inflammatory events in the dry AMD eye and in models of dry AMD. Drusen components trigger inflammasome activation, a cellular pathway that leads to production of cytokines IL-1β and IL-18, which further exacerbate disease progression. Vinpocetine is a dietary compound derived from the periwinkle plant with inhibitory effects on NF-kB, the master inflammatory transcription factor. We investigated the effect of vinpocetine on NF-kB activity, inflammasome activation and cytokine production in the RPE cell model and in an animal model of dry AMD. Methods: ARPE19/NF-kB reporter cells were stimulated with Aβ alone and Aβ with vinpocetine. NF-kB activity was measured using RT-PCR. Wild type rats received a single intravitreal Aβ injection and daily intraperitoneal vinpocetine injection for 3 days, after which eyes were enucleated on day 4. The RPE/choroid was analyzed with immunohistochemistry and Western blot. A suspension assay was used to measure cytokine levels in the vitreous. Results: ARPE19 cells treated with Aβ demonstrated enhanced NF-kB activation and vinpocetine suppressed this response. In vivo, vinpocetine reduced NF-kB intranuclear translocation in the RPE. Immunohistochemistry and Western blot revealed that caspase-1 cleavage and NLRP3 inflammasome activation were significantly inhibited by vinpocetine. Concentrations of IL-1β, IL-18, TNF-α, MIP-3a, IL-6, IL1α were decreased in vinpocetine-treated eyes. Conclusion: These results suggest that the NF-kB pathway is activated in the RPE by drusen component, Aβ, in the RPE and primes the NLRP3 inflammasome and the expression of pro-inflammatory cytokines. NFkB inhibition may limit the chronic inflammatory milieu in the outer retina. Vinpocetine, a well-tolerated dietary supplement, may be a useful NF-kB inhibitor that will have clinical benefit in degenerative conditions associated with chronic inflammation, such as AMD. Lamellar hole epiretinal proliferation Claudine E. Pang1,2,3 David A. Maberley1 Richard F. Spaide2,3 and K. Bailey Freund2,3,4 1. Department of Ophthalmology, University of British Columbia, Vancouver, Canada. Vitreous Retina Macula Consultants of New York, New York, USA. 3. LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear and Throat Institute, New York, USA. 4. Department of Ophthalmology, New York University School of Medicine, New York, USA. 2. Purpose: To determine the prevalence of lamellar hole epiretinal proliferation (LHEP), and compare the functional, morphological and histological characteristics with that of typical epiretinal membranes (ERM). Methods: Retrospective review of spectral-domain OCT imaging of 2030 eyes of 1104 patients with lamellar macular holes, full-thickness macular holes and ERM. A subset of eyes with lamellar macular holes was studied, comparing those with ERM against those with LHEP. Histological study was performed on 2 eyes with lamellar macular holes who underwent vitrectomy and membrane peel of the ERM. Results: Lamellar hole epiretinal proliferation was found to be present in 30% of eyes with lamellar macular holes and absent in eyes with ERM without inner retinal defects. Lamellar macular holes with LHEP had poorer mean visual acuities, larger retinal defects and higher incidence of ellipsoid disruption than those with ERM. Histological study revealed LHEP comprised predominantly of retinal tissue, which stained heavily with glial fibrillary acid protein, a marker of glial tissue. Conclusions: Lamellar hole epiretinal proliferation is a distinct clinical entity, occurring predominantly in lamellar macular holes, and seems to involve more tissue loss and injury than lamellar macular holes with ERM. Lamellar hole epiretinal proliferation was contiguous with middle retinal layers and was confirmed on histological study to comprise of retinal tissue, suggesting a process of proliferation or migration of retinal tissue on the epiretinal surface via the inner lamellar defect. Session 2 – Glaucoma and Cornea Moderator: S. Warner Fibroadipogenic progenitors in thyroid eye disease Aaron Joe, Lin Yi, Val White, Fabio Rossi and Peter Dolman Purpose: Thyroid eye disease (TED) is caused by excessive fibrosis of the extraocular muscles (EOM) and expansion of the orbital fat pad, and is thought to be related to TSH and IGF1 receptor activation. However, the cells responsible for this aberrant growth, remains unknown. Fibro-adipogenic progenitors (FAPs) are perivascular cells that give rise to fibrocytes and adipocytes. Emerging evidence from animal models suggests that FAPs play a central role in modulating the balance between tissue regeneration versus tissue scarring. The purpose of this pilot project is to examine whether FAPs play a role in production of orbital fat and EOM fibrosis associated with TED. Study Design: This is retrospective, immunohistochemistry-based study in which we examine the numbers and the characteristics of FAP cells in previously-obtained, formalin-fixed tissue specimens in TED patients versus normal controls Methods: Similar to initial FAP studies from murine tissues, human FAP cells were identified using a combination of cell surface markers, including negative staining for CD31, CD45 and α7-integrin, and positive staining for CD34 and PDGFr-α. We compared the numbers and position of FAP cells in TED samples vs normal. Results: We were able to identify FAPs in human ocular tissues and show a relationship between FAP numbers and TED. Conclusions: Our study suggests that FAPs may be associated with the development of TED. Stop smoking: breathe easier, live longer and … get glaucoma? Richard J. Symes, Mahyar Etminan, and Frederick S Mikelberg Purpose: Topiramate is known to cause angle closure glaucoma (ACG) via a uveal-effusion mechanism and there is evidence that this adverse effect may also occur with bupropion. Both drugs may be used as therapy for smoking addiction. The purpose of this study was to investigate the association between ACG and prescription of these two medications. Methods: A nested case-control study was conducted using a large health claims database in the United States. The database contained de-identified data pertaining to a cohort of 6,110,723 patients. Cases were defined according to first coding for ACG. For each case, ten controls were selected and matched to the cases using density-based sampling. Adjusted Rate ratios (RRs) were computed for bupropion, topiramate and esomeprazole (control drug). Results: The adjusted rate ratio was 1.09 (CI 0.75-1.59) for bupropion and 2.59 (CI 1.56 – 4.30) for topiramate. In the under 50-age group the adjusted rate ratio was 1.98 (CI 1.02-3.84) for bupropion and 5.30 (CI 2.24-11.04) for topiramate. Conclusions: The risk of ACG in patients under 50 years was doubled in patients taking bupropion and over 5-times higher in patients taking topiramate. Erectile dysfunction in patients with glaucoma Geoffrey Law, Nawaaz Nathoo, Frederick S Mikelberg and Simon Warner Purpose: Recently it has been suggested that open-angle glaucoma (OAG) is associated with higher incidence of erectile dysfunction. However, it is not yet clear whether OAG is an independent risk factor for ED, and whether or not the severity of one pathology correlates with the other. We performed a retrospective, observational clinical study to test the hypothesis that in patients with primary glaucoma and ED there will be a positive correlation in severity between the two conditions independent of other risk factors, including topical beta-blocker use. Methods: Patients with primary glaucoma, including open-angle and normal tension glaucoma were surveyed for erectile function. Age-matched controls from a community-based ophthalmology practice were also surveyed. Data was gathered through the use of the International Index of Erectile Function (IIEF) Questionnaire. Results: Preliminary results have been collected to date. Two-tailed unpaired t-test comparison of ED prevalence in glaucoma (n=20) vs. non-glaucoma (n=20) patients was significant (P=0.01). Unpaired t-test of VFI in glaucoma patients (n=20) with and without ED was not significant (P=0.51); however these findings may change as subsequent data is collected and analyzed. Conclusions: Prior diagnosis of glaucoma is associated with increased prevalence of erectile dysfunction. Further data collection and statistical analyses are required to elucidate whether or not there is a correlation in severity between ED and glaucoma. Given the similar risk factors between the two diseases (hypertension, dyslipidemia, diabetes), shared pathways in disease progression are likely involved in the development of ED in glaucomatous patients. Further insight by prospective studies would allow for the potential development of novel treatments for both diseases. Anterior segment optical coherence tomography measurements predictive of IOP lowering after cataract surgery Brennan Eadie, Morgan Heisler, Simon Warner, and Paul Mackenzie Objectives: To validate the use of a newly developed anterior segment Optical Coherence Tomography (ASOCT) imaging system and elucidate the anterior segment anatomical predictors of intraocular (IOP) change following cataract surgery. Design: Prospective, comparative observational study. Participants: Twenty eyes of twenty patients awaiting cataract surgery were included in this study. Methods: Consecutive patients from a single ophthalmologist’s practice were offered enrollment in this study. Preoperative refractive error, IOP, ultrasound-determined axial length and keratometry measurements were obtained. In addition, AS-OCT was conducted and the following parameters were evaluated: corneal thickness (K thickness), anterior chamber depth (ACD), anterior chamber width (ACW), pupil width (PW), scleral spur to Schwalbe’s line distance (SS-SL), anterior chamber angle (ACA), angle opening distance 500 and 750 (AOD500, AOD750), angle recess area 500 and 750 (ARA500, ARA750), trabecular space area 500 and 750 (TISA500, 750), iris thickness 750 and 2000 (IT750, IT2000), iris chord length (ICL), iris curvature (IC), and iris concavity ratio (ICR). Post-operative measurements at 1, 6 and 12 months are in progress. Results: The mean age was 72 (+/-8; range 56-89). Ten males and ten females were included. There was a wide range of spherical equivalents (SE) in our population (mean = -1.9+/-4.0; range -9.63 to +2.25). Preoperative IOP was 15.1+/-2.7 (range = 8 to 19). SE was significantly inversely correlated with axial length (R=-0.89, P<0.001), ACD (R=-0.50, P<0.05), ACA (R=-0.54, P<0.05), AOD500 (R=-0.58, P<0.01), and AOD750 (R=-0.55, P<0.05). Conclusions: The newly developed AS-OCT appears to generate data consistent with what is known about anterior segment anatomy and its relationship to refractive error. Post-operative AS-OCT data will likely provide valuable information regarding the effects of cataract surgery on anterior segment anatomy and associated changes in intraocular pressure. Corneal cross-linking in pediatric patients with progressive keratoconus Stephanie Wise, Christian Diaz, Karolien Termote, Paul J. Dubord, Martin McCarthy, and Sonia N. Yeung Purpose: To evaluate the outcomes of corneal cross linking (CXL) in the treatment of keratoconus in pediatric patients. Specifically, the impact of CXL on uncorrected distance visual acuity (UDVA), best corrected distance visual acuity (BDVA), manifest refraction, keratometric measurements and higher order aberrations are investigated. Methods: This is a retrospective, observational case series of patients 18 years old and younger with progressive keratoconus who underwent CXL from January 2009 to August 2013. Preoperative and one year postoperative data including BDVA, manifest refraction, mean and steepest keratometry readings and corneal aberration measurements were extracted from clinical charts and topographical imaging. Visual acuity was converted to logMAR scale and mean refractive spherical equivalent (MRSE) was calculated from manifest refraction. Results: The group consisted of 39 eyes from 28 patients, there were 21 males (75%) and 7 females (25%), mean age was 16.3 years old (range 11-18, SD=1.81). UDVA did not change significantly (preoperative UDVA=1.2logMAR, SD=0.57 and postoperative UDVA=0.90logMAR, SD=0.67, p=0.19). BDVA did not change significantly (preoperative BDVA=0.34logMAR, SD=0.27 and postoperative BDVA=0.34logMAR, SD=0.23, p=0.5). There was no significant change in mean K; preoperative mean K=48.49 (SD=5.44) and postoperative 48.25 (SD=4.74), p=0.34. Mean MRSE did not change significantly; -3.29D (SD=4.04) to -3.53D (SD=4.07), p=0.31. There were corneal aberration measurements available for 10 eyes. Stability of aberrations was demonstrated. There were no complications noted. Conclusion: This study suggests that CXL is a safe and effective procedure that halts the progression of keratoconus in pediatric patients in one year follow up. Graft free Ahmed valve implantation through a 6 mm scleral tunnel Kailun Jiang and Gdih Gdih Purpose: To evaluate the safety and efficacy of Ahmed glaucoma valve (AGV) tube implantation through a 6mm scleral tunnel (graft free technique). Methods: Retrospective and prospective cohort study. The 95% confidence interval for fractional survival at any particular time was calculated using the Kaplan-Meier method. Failure was defined as: 1. IOP <6mmHg or IOP > 21mmHg on 2 consecutive visits after 3 months 2. Additional surgical intervention to control IOP 3. No light perception (NLP) Results: 143 eyes were implanted with graft-free AGV with a success rate of 80.9% at 2 years. 21 eyes failed: 6 NLP, 2 persistent hypotony, 6 secondary AVG, 8 AGV extractions. The rate of hypotony peaked at 32% on post-operative day (POD) 1, reducing to 2% by 6-weeks. Transient flat anterior chamber developed in 7% of eyes. 10% of eyes experienced a hypertensive phase (mean IOP=25.7mmHg). Pre-operatively, eyes were on average receiving 3.7-units of glaucoma medication. Post-operatively, 18 eyes required no medication for IOP control. Of the eyes requiring postoperative glaucoma medication, 38% restarted during week 4; an additional 25% of eyes were restarted 6 weeks post-operatively. By 6-month eyes were on average using 2.1-units of glaucoma medication. Hyphema was the most common (15%) early postoperative complication. The rates of conjunctival and scleral dehiscence within the first 2-years were 2.1% and 0.7% respectively. Within our institution, excluding the valve cost, there is a 39-45% ($192-376CAD) cost reduction with the graft-free technique. Intraocular lens power calculation formulas for flat corneas Henry C Chen, Michelle A Ceniza, and Kevin N Wade Purpose: A retrospective study comparing the post-operative refraction in cataract surgery patients with flat corneas versus the predicted refraction of SRK/T, Holladay, Hoffer Q and SRK/T formulas is presented. Study Design: Cataract surgery is the most commonly performed refractive surgery procedure. Advancements in intraocular lens (IOL) design and power calculations have allowed more accurate correction of spherical refraction. IOL power calculations use empirical regression formulas and theoretical formulas; the former are now rarely utilized. Theoretical formulas consist of a lens constant, keratometer readings, axial length, and estimated post-operative anterior chamber depth (ACD), also known as the estimated effective lens position (ELP). Modern theoretical formulas differ between each other in the calculation of the ELP, which depends on axial length and corneal curvature (K). Commonly used modern theoretical formulas include the SRK/T, Holladay and Hoffer Q formulas. Clinically, there is minimal difference between the formulas for the average eye of average length and corneal curvature; however, accurate predictions of IOL lens powers for flat corneas are more variable. Methods: Patients of forty-seven eyes (27 left and 20 right eyes) with flat corneas and Tecnis 1 intraocular lenses, defined as having an average corneal power (K) of less than 41.0 diopters, were determined by a Zeiss Atlas 9000 topographer. Patients with LASIK and PRK were excluded. Intraocular lens power calculations were determined using SRK/T, Holladay, Hoffer Q and Haigis formulas. The predicted spherical equivalent value of the intraocular lens selected was tabulated. The post-operative refraction data of the patients, including spherical equivalent, was compared versus the predicted values with the intraocular lens power formulas. Results: In the study sample, the mean flattest, steepest, and average K was 40.01±0.49D, 40.60±0.53D, and 40.31±0.48D respectively. Mean post-operative spherical equivalent was -0.160±0.521. The mean SRK/T formula predictive spherical equivalent was -0.54±0.26. It was found to be statistically significantly different (two-tailed paired t-test, P <0.05) from the mean post-operatively spherical equivalent. The mean Holladay formula predictive spherical equivalent was -0.29±0.27. This was not found to be statistically significantly different from the mean post-operatively spherical equivalent. The mean differences between post-operative spherical equivalent and the predictive formulas were 0.38±0.49 and 0.13±0.46 for the SRK/T and Holladay formulas, respectively. Conclusions: A statistically significant difference was found between the patient sample outcomes at greater than 6 weeks and both the SRK/T as well Holladay intraocular lens power calculation formula predictions. This suggests that the Holladay formula may be more accurate in predicting post-operative spherical equivalents in flat corneas compared to the SRK/T formula. Session 3 – New Tools and Procedures Moderator: O. Moritz A survey of community family physicians about ophthalmic knowledge and skills Heather L. O’Donnell and Kevin N. Wade Purpose: To assess the baseline knowledge of community family physicians with regards to their ophthalmic knowledge base and eye exam skill set and to determine whether participation in a continuing medical education (CME) seminar is of value in improving knowledge and skills. Methods: Seventy-five community family physicians that registered for an ophthalmology CME seminar were invited to participate in a survey of their knowledge and skills related to ophthalmology. Thirty-seven survey questions were divided into either knowledge or skills domains. Participants completed the survey prior to and within 2 weeks of completing the CME seminar. Demographic data was collected and survey responses were analyzed. Results: Of the 75 participants, 40 people completed the pre-CME survey and 27 people completed the postCME survey. Eleven (27.5%) were family practice resident physicians and the remainder were practicing community family doctors who had been in practice for either 1-5 years (37.5%), 10-20 years (12.5%) or more than 20 years (25%). Twenty-nine (72.5%) participants reported receiving no ophthalmology training after medical school and medical school training was reported to be 1-2 weeks for most participants (96.4%). Of the 17 participants who completed both the pre and post seminar surveys their skills scores improved from a mean of 71.1% to 91.1% (p < 0.001) and their knowledge scores improved to 58.6% to 83.9%(p<0.001). Conclusions: Given the low volume of training during medical school in ophthalmology, continuing medical education seminars for family physicians are an effective way to provide much needed education in this important topic area. Big data visualizations in ophthalmology Aaron Y. Lee, Adnan Tufail and David Albiani Purpose: Rapid accumulation of real-world outcomes data from raw extracted data from Electronic Medical Records (EMR) opens the world of Big Data to the field of medicine. One of the many challenges facing this new area is the construction of visualizations and interpretations of large-scales of data. Methods: Anonymized structured data were collected from 24 centers using an EMR system. The primary outcome was the mean VA at year 1, 2, and 3. Secondary measures included the number of clinic visits and injections. Data was directly processed from raw EMR database data using Ruby and R. Results: The study included 18,448 treatment-naive eyes receiving over half a million ranibizumab treatments over 7 years with 2.3 million clinic visits worth of data. A total of 196 million data elements were captured and processed to create visualizations. Conclusions: We present novel visualizations to explore and understand large clinical datasets in ophthalmology. The slit lamp proptometer: a novel digital slit lamp exophthalmometer Yvonne Chung, Elie Eid, Michael J. Davies, and Peter J. Dolman Exophthalmometry is essential in assessing the presence of orbital disease and detecting any interval clinical change. It consists of measuring the anteroposterior position of the globe relative to the orbital rim. There is currently a lack of a single instrument that provides consistently accurate readings with minimal intraobserver and interobserver error in today’s commonly employed exophthalmometers Inaccuracies in measurement of proptosis can have clinical ramifications for the patient. It can influence the decision to investigate proptosis or impact preoperative surgical planning in orbital decompression and the amount of fat or bony reduction. Most instruments such as the commonly used Hertel exophthalmometer uses the lateral orbital rim as a fixation and reference point to measure the position of the globe. We designed a slit lamp mounted digital exophthalmometer that makes measurement of proptosis simpler, more accurate (the caliper used measures in millimetres to 2 decimal places) and unbiased due to the fact that the reading is not visible during the measurement process as it is with the Hertel and other exophthalmometers. It is built from inexpensive and readily sourced materials and easily attachable to any slit lamp. We believe that our prototype model provides accurate and reproducible measurements and aim to test its accuracy against the Hertel exophthalmometer, currently the instrument most commonly employed in clinical practice. Subthreshold diode microPulse photocoagulation for persistent subretinal fluid following macula-off retinal detachment surgery: three case reports Herman Johal and Andrew Lukaris Background: Persistent submacular fluid (SMF) accumulation following successful macula-off retinal detachment (RD) surgery may compromise final visual acuity (VA) and photoreceptor physiology. Currently there are no treatment modalities for routine intervention. Subthreshold diode MicroPulse (SDM) photocoagulation has been shown to effectively accelerate resorption of SMF in similar disease states and conditions. Methods: We utilized SDM for three patients with persistent SMF following successful RD surgery. There average time between RD surgery and SDM was just over 4 months. SDM (λ=810nm) parameters: 200ms exposure duration, 125 micron spot size, 1800mW power and 5% duty cycle. Changes in SMF and foveal thickness were examined using optical coherence tomography (OCT). Results: We observed significant to complete resolution of persistent SMF on OCT and improvement of visual symptoms following SDM administration in all three patients. No intra- or post-operative visible burn end point at the retina was observed following SDM administration and VA remained stable in all three patients during follow up. Conclusion: SDM may offer a safe and effective means to accelerate the recovery of persistent SMF following successful macula-off RD surgery and potentially improve final VA in these patients. Test characteristics of point of care ultrasound in the emergency department for the diagnosis of retinal detachment Byron Silver, David Maberley, Donna Lee, and Daniel Kim Purpose: To assess the test characteristics of point of care ultrasound in detecting retinal detachment. Methods: Emergency department physicians (EP) who are ultrasound (US) fellowship trained can participate in this study. Additionally, EP’s who are not US fellowship trained may participate after completing an ocular ultrasound course. Patients presenting to the Vancouver General Hospital Emergency Department with flashes and or floaters will be offered participation in the study. Each participant will undergo a bedside US by the EP who will then document the presence or absence of a retinal detachment based on the interpretations of the US. Each patient will then have a full ophthalmic assessment by a retinal specialist to confirm the actual diagnosis. Results: This study is in its early stages. Available results will be presented at the UBC Department of Ophthalmology and Visual Sciences Research Day. Conclusion: Results are pending, but we hope to determine whether Emergency Department ultrasound is a useful tool in the diagnosis of retinal detachment and may improve ophthalmic care. Quantitative non-invasive angiography of the fovea centralis using speckle variance optical coherence tomography Zaid Mammo, Chandrakumar Balaratnasingam, Paula Yu, Jing Xu, Morgan Heisler, Paul Mackenzie, Andrew Merkur, Andrew Kirker, David Albiani, Marinko V. Sarunic, and Dao-Yi Yu Purpose: To demonstrate the utility of speckle variance optical coherence tomography (svOCT), a noninvasive angiographic technique, for providing clinically useful quantitative information about the foveal vasculature. Design: Evaluation of a diagnostic technology. Participants: Nineteen normal subjects, 4 diabetic patients and 16 human cadaveric eyes. Methods: Twelve normal human eyes were imaged with svOCT (1060nm 100kHz custom built system) and fluorescein angiography (FA; Topcon TRC-50DX with 5.0 megapixel resolution camera). Manual tracing techniques were used to quantify the foveal vasculature. Reproducibility of these measurements was determined. The foveal avascular zone (FAZ) was imaged in 25 normal eyes using svOCT and in 15 donor eyes using confocal scanning laser microscopy. Retinal capillary plexuses in donor eyes were perfusionlabelled with phalloidin conjugated to Alexa Fluor 546. FAZ metrics including area, perimeter, greatest diameter and lowest diameter were determined using manual tracing techniques. Four diabetic patients were imaged with svOCT. Quantitative measurements of capillary density and FAZ were performed. Main Outcome Measures: Comparison of capillary density measurements between svOCT and FA. Comparison of FAZ measurements between svOCT and histology. Correlations between visual acuity, FA findings, Spectral-Domain OCT findings, central subfield thickness (CST) and quantitative svOCT measurements in diabetic patients. Results: Capillary density measurements were significantly greater in svOCT than FA (31.2 ± 1.6% vs. 19.3 ± 1.9% of total tissue area; P < 0.001). Measurements were highly reproducible (all P > 0.366). All FAZ metrics were significantly lower in histology than svOCT (all P < 0.001). FAZ metrics were greater in diabetic eyes. In 3 out of 4 diabetic eyes with a disrupted foveal terminal capillary ring the visual acuity could not be improved to 20/30 or better despite having a near-normal CST. There was a strong inverse correlation between FAZ area and CST. Conclusions: svOCT permits precise, reproducible and non-invasive visualization of the human foveal vasculature. The anatomical status of the foveal vasculature could be an important predictor of bestcorrected visual acuity in diabetic retinopathy. svOCT may therefore be an important adjunctive imaging modality that can be used in conjunction with OCT and FA to manage patients with retinal vascular diseases. Session 4 – New Disease Models Moderator: S. Warner Animal model of dry AMD induced by chronic exposure to a drusen component Wade Gao, Ruozhou Tom Liu, Sijia Cao, Eleanor To, Aikun Wang, Jing Z. Cui, and Joanne A. Matsubara Purpose: Our earlier studies demonstrated that a drusen component, Aβ, triggers a short lasting proinflammatory response in retinal pigment epithelium (RPE), both in vitro and in vivo, through the activation of NF-κB and NLRP3 inflammasome. Furthermore, we demonstrated that the inhibition of NF-κB activation abolished the Aβ induced caspase-1 cleavage and cytokine production in RPE in vivo. In this study, we prolonged the pro-inflammatory milieu in the outer retina by making multiple Aβ injections, in order to better model the chronic pro-inflammatory events proposed to underlie the pathogenesis of the dry form of agerelated macular degeneration (AMD). Methods: Long-Evans rats were intravitreally injected with Aβ1-40 once every 4 days for a period of 12 days and then sacrificed. Next, the vitreous humor was collected and levels of secreted cytokines were evaluated. mRNA levels of the major cell death genes were analyzed by real-time PCR. Protein levels of the cleaved caspase-1/-3, NF-κB and IL-18 were assessed by western blot or immunohistochemistry. Morphometric measurements to analyze Aβ-induced changes in the RPE were obtained using custom algorithms designed for Photoshop. Results: Vitreous samples from Aβ injected eyes showed more than 1.5-fold increase in MIP-3α, IL-1β, VEGF, and MCP-1 compared to controls. RPE/choroid complex from Aβ injected eyes revealed more than 2fold upregulation of characteristic cell death genes and also a significant increase in the levels of caspase-1/-3 cleavage and IL-18 secretion, when compared with the controls (p<0.05). The percentage of NF-κB immunoreactive nuclei in both ONL and RPE layers suggested robust NF-κB activation in Aβ injected eyes compared to controls. Moreover, morphometric analysis showed enlarged, swollen RPE cell bodies in Aβ injected eyes, suggestive of multiple cell death mechanisms. Conclusions: Consistent with our previous studies, we continued to observe elevated pro-inflammatory cytokine secretion in vitreous, and enhanced NF-κB and inflammasome activation in RPE. The existence of swollen, dysfunctional RPE and the increased cleavage of caspase-1 and caspase-3 in RPE/choroid suggest the involvement of different cell death mechanisms in response to prolonged Aβ exposure. Further investigations are warranted to fully characterize this model and its relationship to AMD. Utilizing CRISPR/Cas9 for one-step cell specific knockouts in Xenopus laevis Joanna Feehan and Orson Moritz Purpose: Xenopus laevis (African clawed frog) is widely used in vision research. Although transgenic X. laevis are generated relatively easily, researchers have previously been unable to engineer knockouts (KO) or knockdowns in X. laevis. New techniques for genome editing using CRISPR/Cas9 have been applied to related organisms, including X. tropicalis. We will develop a CRISPR/Cas9-based technique for genome editing in X. laevis, using the Rhodopsin (RHO) gene as a target. Rhodopsin is the photosensitive pigment of rod photoreceptors and is also a model cargo for ciliary trafficking studies. RHO KO X. laevis may be useful for investigating trafficking properties of rhodopsin mutants, such as those responsible for certain types of retinitis pigmentosa. Rhodopsin KO animals are anticipated to have a phenotype that is easily detectable by histology (no rods in complete KO), immunoassay (reduced rhodopsin) and physiology (reduced or no rod electroretinogram (ERG). Methods: We have established the effectiveness of CRISPR/Cas9 technology by injecting fertilized embryos with guide RNA (sgRNA) targeting the X. laevis RHO gene and mRNA encoding Cas9 endonuclease. We will engineer transgenic animals with a Cas9/sgRNA expression cassette by restriction enzyme mediated integration (REMI) for establishment of KO nonmosaic primary animals. At 14 days post-fertilization, rhodopsin levels in the eyes of the resulting animals are determined by immunoassay and compared to rhodopsin levels from control animals expressing a null sgRNA with non-specific targeting. Results: The mRNA injection procedure results in approximately 50% reduction in the average rhodopsin protein levels in injected embryos, indicating that the majority of animals have at least a partial knockout phenotype. The histological phenotype of these compromised mutants included as expected missing or shortened rod outer segments relative to wild-type embryos. Conclusions: CRISPR/Cas9-based techniques can result in very high knockout rates in X. laevis. The efficiency is sufficiently high that phenotypes can be successfully examined in primary knockout animals. Timeline of asymmetrical and symmetrical motor neuron loss in a zebrafish model of amyotrophic lateral sclerosis Jessica Morrice, Cheryl Gregory-Evans and Christopher A. Shaw Purpose: Amyotrophic lateral sclerosis (ALS) is depicted by the progressive degeneration of upper and lower motor neurons. Most patients display distinct unilateral neurodegenerative symptoms, which progress bilaterally throughout disease progression. An unexplored area in this field is the asymmetrical onset of motor loss at a cellular level. ALS pathology displays simultaneous motor neuron degeneration and central nervous system (CNS) inflammation, and microgliosis has been shown to directly contribute to the degenerative process. However, the inherent features of microglial-neuronal interactions during ALS pathogenesis remain poorly understood. Hypothesis: There will be naturally pre-existing asymmetries in the distribution of resident microglia within the CNS which will predict any asymmetry in neurodegeneration. Aim 1. To determine the stage of disease when colocalization initiates between motor neuron apoptosis and microgliosis. Aim 2. To determine if there is a spatial pattern where motor neurons begin to undergo apoptosis, and if a similar pattern exists for microglia proliferation and M1 vs M2 phenotype. Methods: Double transgenic zebrafish embryos will be used to monitor microgliosis and neuronal cell death spatiotemporally in vivo to create a “map” of neurodegeneration in a genetic and sporadic model of ALS. Colocalization between microglia and motor neuron apoptosis will be visualized at early stages of disease under the confocal microscope. Results: We expect that any asymmetry of initial disease presentation is primarily due to pre-existing asymmetry in resident microglia, and that microglia phenotype will directly dictate motor neuron susceptibility to degeneration. Conclusions: This research could provide insight into cellular mechanisms involved in the neurodegenerative process and also for investigating motor neurons that are susceptible to degeneration in ALS. Stem cell based gene therapy for angle closure eye defects in aniridic glaucoma Vahitha S. Nizamudheen and Cheryl Y. Gregory-Evans Introduction: Mesenchymal stem cell (MSC) therapies hold a promising future in regenerative medicine. The Pax6 transcription factor drives anterior segment morphogenesis in the eye, and one of the direct downstream targets of Pax6 is Tgfβ2. Our aim is to develop genetically modified MSCs to deliver Tgfβ2 to target the defective tissues, which in turn control the intraocular pressure (IOP) in the haploinsufficient Pax6 mouse model. Methods: Full length mouse Tgfβ2 gene was introduced into pIRES-DSRED2 vector and the construct containing Tgfβ2 gene was confirmed by DNA sequencing. This pIRES-DSRED2-Tgfβ2 construct was transfected into adipose-derived MSCs by the electroporation method. The level of expression of Tgfβ2 protein was quantified by ELISA assay. The genetically modified MSCs will be transplanted into anterior chamber of the eye for both wildtype and Pax6 mutants by intraocular injection at postnatal day 5. In vivo Tgfβ2 protein expression are analyzed in ocular tissue by ELISA, Western blotting, quantitative RT-PCR and immunohistochemistry. Structural and functional benefits are assayed by optical coherence tomography, electroretinography and optokinectic tracking assays. A Tonolab tonometer will be used to measure the IOP levels in genetically modified MSC treated eyes and untreated controls. Results: Thus far, the targeting vector has been prepared and introduced into MSCs. The plasmid containing Tgfβ2 was electroporated and cells stably expressing Tgfβ2 were isolated successfully. In future, these experiments will determine the feasibility of using genetically modified MSCs to deliver Tgfβ2 to the eye, as there are insufficient levels of this protein due to a reduction in Pax6 activity. Specifically we will demonstrate whether this strategy is sufficient to improve normal postnatal eye development to overcome defects and reduce the IOP in the mutant eye. Conclusions: We anticipate that the stem cell treatment will improve the structure of the iridocorneal angle making the outflow of aqueous humor more effective, thereby decreasing the level of IOP. The outcome of this cell based therapy could provide effective long term therapeutic benefits that may be able to replace the inadequate medical and surgical procedures. Identifying the ‘‘driver’’ genes for multi-systemic 2p15-16.1 microdeletion syndrome using in vivo zebrafish assays Hani Bagheri1,2, Chansonette Badduke1,2, Ying Qiao1,2, Xianghong Shan3, Cheryl Gregory-Evans3, and Evica Rajcan-Separovic1,2 1 Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver Child & Family Research Institute, Vancouver; 3 Department of Ophthalmology, University of British Columbia, Vancouver 2 Background: The 2p15-16.1 microdeletion syndrome (OMIM 612513) is a rare genetic disorder caused by de novo deletion of a small segment of chromosome 2 that we first described in two phenotypically similar individuals with intellectual disability (ID) (Rajcan-Separovic et al. JMG, 2007). So far, 23 subjects with this microdeletion have been identified world-wide who share common clinical features including delayed neurocognitive development and consistent craniofacial defects e.g. microcephaly, brain structure anomalies, and facial dysmorphism. Microdeletions in the 23 subjects span ~9.8 Mb and include 37 coding genes. The deletions are extremely variable in size, ranging from ~0.5 Kb to ~8 Mb with median deletion size of 3.14 Mb. This variability and the existence of non-overlapping deletions within this region complicate efforts to delineate a common critical region for this syndrome. Therefore, the causative genes for this condition remain to be elucidated. Methods: Five candidate genes, XPO1, USP34, REL, FANCL, and VRK2 were shortlisted based on their frequency of deletion, haploinsufficiency prediction (using the previously described approach by Huang et al., PLoS Genet., 2010), cellular function, and expression in developing brain and in patient cells. The orthologues of these candidate genes were then targeted by RNA anti-sense oligomers called morpholinos to obtain gene knock-down in zebrafish embryos. The embryonic development was monitored in knock-downs and in controls at 1 and 3 days post-fertilisation. Results: Our preliminary results suggest that the knock-down of XPO1 and REL orthologues in zebrafish results in phenotypic features similar to those observed in human subjects. Specifically, the results suggest that a drop of ~50% of XPO1 gene expression causes abnormal growth, reduced head size and anomalous brain development in fish. The knock-down of zebrafish orthologues for USP34, FANCL, and VRK2 genes, however, did not result in any visible phenotypic abnormalities. Conclusions: We used zebrafish embryos as a valuable model organism to check for the in vivo effect of knock-down of genes that are involved in the 2p15-16.1 microdeletion syndrome and identified XPO1 and REL to be the ‘‘driver’’ genes for the consistent phenotype observed in the patients. This finding will set the foundation for improved understanding of their function and roles in brain development. It will also help advance our understanding of pathways and mechanisms of other neurodevelopmental abnormalities, which are critical to achieving the longer term prospect of improved anticipatory care, counseling and therapy. Session 5 – Pediatric & Neuroopthalmology Moderator: O. Moritz Pediatric infectious keratitis at tertiary referral centers in Vancouver, British Columbia Gelareh S. Noureddin, Sachiko Sasaki, Andrea L. Butler, Peter Tilley, Diane Roscoe, Christopher J. Lyons, Simon P. Holland, and Sonia N. Yeung Purpose: To report the clinical and microbiological profiles of pediatric patients with infectious keratitis requiring corneal scraping for diagnosis in Vancouver, British Columbia. Methods: In this observational case series, the microbiology results and medical records of 17 eyes with microbial keratitis in 16 children aged 17 years or younger were retrospectively reviewed. These patients had undergone diagnostic corneal scraping for cultures and sensitivities between May 2006 and April 2011 at BC Children’s Hospital or Vancouver General Hospital Eye Care Centre in Vancouver, Canada. Demographic information, clinical features, predisposing factors, results of microbiology studies, antibiotic sensitivities, treatment course and outcomes were analyzed. Results: The mean age of patients was 11±5.7 years (range 1 -17 years) and the male to female ratio was 1.4:1. Major predisposing factors were contact lens wear (6/17; 35%) and pre-existing ocular surface conditions, including blepharitis (3/17; 18%) and Stevens-Johnson Syndrome (3/17; 18%). The most commonly isolated microorganisms were Staphylococcus epidermidis and Acanthamoeba. Acanthamoeba was isolated in 67% of contact lens related corneal ulcers, while 33% were associated with infection with Pseudomonas aeruginosa. Final visual acuity was better than 20/60 in 9 out of 16 patients (56%). Three patients subsequently required surgical management with either penetrating keratoplasty or DALK for treatment of corneal scarring. Conclusions: Contact lens wear and pre-existing ocular surface conditions are significant risk factors for the development of infectious keratitis in our pediatric population. Knowledge of regional patterns of infection and susceptibility are essential in assuring prompt treatment of this potentially sight-threatening condition. The effects of homonymous hemianopia on experimental studies of alexia Cristina Rubino, Carol Bao, Alisdair J G Taylor, and Jason J S Barton Purpose: Pure alexia is characterized by an increased word-length effect in reading. However, this disorder is usually accompanied by right homonymous hemianopia, which itself can cause a mildly increased wordlength effect. Some alexic studies have used hemianopic patients with modest word-length effects: it is not clear a) whether they had pure alexia and b) if not, whether their results could be explained by the field defect. Our goal was to determine if impairments in visual processing claimed to be related to alexia could be replicated in homonymous hemianopia alone. Methods: Twelve healthy subjects performed five experiments used in two prior studies of alexia, under both normal and simulated hemianopic conditions, using a gaze-contingent display generated by an eye-tracker. Results: We replicated the increased word-length effect for reading time with right homonymous hemianopia, and showed a similar effect for a lexical decision task. Simulated hemianopia impaired scanning accuracy for letter or number strings, and slowed object part processing, though the effect of configuration was not greater under hemianopic viewing. Hemianopia impaired the identification of words whose letters appeared and disappeared sequentially on the screen, with better performance on a cumulative presentation in which the letters remained on the screen. The reporting of trigrams was less accurate with hemianopia, though syllabic structure did not influence the results. Conclusions: We conclude that some impairments that have been attributed to the processing defects underlying alexia may actually be due to right homonymous hemianopia. Our results underline the importance of considering the contribution of accompanying low-level visual impairments when studying highlevel processes. Current patching protocols for amblyopic patients among currently practicing strabismus specialists (CONSENSUS) Rebecca A. Rewi, Vaishali, Mehta, Christy Giligson, and Deborah Giaschi Purpose: The aim of this study was to examine what management strategies and techniques are being employed to treat children with anisometropic amblyopia (AA) and strabismic amblyopia (SA) among pediatric ophthalmologists and orthoptists currently practicing in North America. Methods: A one-time invitation to complete a 28-question electronic web-based survey was distributed via electronic mail to active members of The Canadian Orthoptic Society, The American Association of Certified Orthoptists and The Canadian Association of Ophthalmology and Strabismus. The response window was left open for a period of 8 weeks. Using Likert scale responses, the questionnaire assessed respondent’s current management protocols with regards to patients presenting with AA or SA. Results: A total of 103 participants completed the survey, 87/103 (84%) of respondents were clinical orthoptists, while 16/103 (16%) were pediatric ophthalmologists. Most respondents 78/103 (76%) see 21+ amblyopic patients per month. While most respondents 61/98 (62%) treated AA patients with an average of 24 hours of patching per day, a large minority (38%) treat AA patients differently, 7/98 (7%) prescribed 1-2 hours patching/day and 30/98 (31%) prescribed 4-6+ hours/day. Similarly, when treating SA, 56/98 (57%) prescribed an average of 2-4 hours of patching per day, with a large minority (43%) treating SA differently, 7/98 (7%) prescribed an average of 1-2 hours daily and 36/98 (36%) prescribed 4-6+ hours/day. Interestingly, 70/96 (72%) of participants were not interested in the creation of standardized North American patching protocols for AA and SA. Conclusion: Our survey indicated that most practitioners who manage AA and SA see a substantial volume of patients with amblyopia monthly. However, discrepancy exists with regards to management of patients with AA and SA throughout North America. Surprisingly, there is little interest in creation of standardized North American protocols for AA and SA management despite evidence to show that discrepancies in management exist. Synthesis of current evidence via systematic review and/or meta-analysis is required to assess best practice daily patching efficacies for patients with AA and SA. Global motion perception deficits in children with amblyopia Kimberly Meier1, Brian Sum2, and Deborah Giaschi2 1 Department of Psychology, University of British Columbia Department of Ophthalmology and Visual Sciences, University of British Columbia 2 Introduction: Amblyopia is diagnosed and treated based mainly on deficits in visual acuity. However, additional deficits in spatial vision and motion perception may prove to be clinically useful. The current study focuses on deficits in global motion perception. Previously, we showed that coherence thresholds for global motion perception are immature in 5 year olds with normal vision when smaller spatial and temporal displacements are used to create a stimulus, but adult-like when larger values are used. We hypothesize that coherence thresholds in children with amblyopia will be similar to controls for parameters that mature early in life, but abnormal for parameters that take longer to mature. Methods: Coherence thresholds were assessed in 22 children with amblyopia (7¬-16 years, M = 11.2) and age-matched controls. Six combinations of spatial and temporal parameters were used: spatial displacement was 1, 5, or 30 arc min; temporal displacement was 17 or 50 ms. Results: As a group, children with amblyopia had motion deficits in the amblyopic eye for the smaller spatial displacements at both temporal displacements. There was no group deficit in the clinically unaffected fellow eye, but some individual children did show fellow eye deficits. Conclusion: Visual deficits in amblyopia are not restricted to visual acuity. Deficits in global motion perception point to a compromised visual system that might benefit from treatments beyond occlusion therapy. Voice processing in developmental prosopagnosia Ran (Richard) Liu, Sherryse Corrow , Raika Pançaroglu, Brad Duchaine, and Jason J S Barton Purpose: Prosopagnosia is a selective impairment of face recognition, but voice recognition, another function involving the anterior temporal lobe, has rarely been evaluated to confirm that it is modality-specific. Our previous work has shown that acquired prosopagnosic patients with right anterior temporal lesions have intact voice recognition, while bilateral anterior temporal lesions can impair both face and voice recognition. The anatomic basis of the developmental form of prosopagnosia remains uncertain, and the status of voice recognition is also not known. Methods: We studied 73 control subjects and 12 subjects with developmental prosopagnosia, whose diagnosis was confirmed on tests of famous face familiarity and short-term familiarization, the Warrington Recognition Memory Test and the Cambridge Face Memory Test. We developed two novel tests: a match-tosample test of voice discrimination and a test of short-term familiarity for voice recognition, and administered a questionnaire about face and voice identification in daily life. Results: Eleven subjects had intact voice discrimination and voice recognition, with scores superior to those for face recognition. One subject was impaired on voice discrimination and borderline for voice recognition, with equivalent degrees of impairment for both face and voice recognition. The questionnaire results show that the prosopagnosic subject that showed mild impairment in voice processing was unaware he had any voice processing impairments. Conclusion: Most subjects with developmental prosopagnosia have a modality-specific disorder of face recognition. However, there may be heterogeneity—in some subjects, prosopagnosia may be one component of a multi-modal impairment of person recognition. Tests of voice recognition may help increase the accuracy and specificity of the process of diagnosing prosopagnosia. Pre-operative prism adaptation testing: selection criteria and its long term efficacy in acquired esotropic patients Denoshaa Jeyatheswaran and Deborah Giaschi Prism adaptation testing (PAT) has been implemented on patients with acquired esotropia, by means of reducing the angle of deviation with a minimum number of surgeries. The prism adaptation test is used preoperatively to predict the maximum surgical target angle, by assessing results specific to two groups of patients, responders and non-responders. Prism adaptation testing serves as a good indicator in evaluating postoperative motor and fusion potential in patients, while decreasing the prospects of surgical overcorrections. The purpose of this study is to investigate the one- year stability outcome in patients who were prism adapted and operated for either the original angle, or the adapted angle of deviation, in addition to identifying common characteristics that can be used to predict surgical success. A retrospective chart review between 2011-2014 was conducted of all patients given the diagnosis of acquired esotropia and undergoing surgery, seen by one ophthalmologist in the Ophthalmology clinic at BC children’s hospital. A sample size of 20 esotropic patients was collected identifying 14 acquired subjects, with 12 that underwent pre-operative prism adaptation testing. Orthotropia was achieved in 7 (70%) patients, while 3 (30%)s showed a poor surgical outcome by demonstrating a residual esotropia by the end of a one-year follow-up period. Patients operated for the original angle were compared with patients operated for the newly adapted angle, to identify common variables(s) that contributed to a poor surgical outcome in patients that were confirmed responders pre-operatively. NOTES Program Objectives The program brings together UBC Ophthalmology experts in comprehensive ophthalmology, paediatrics, neuroscience, glaucoma, oculoplastics, and retina. Clinically relevant research will be emphasized in this update of the latest research in these areas. Topics to be covered include: DEVELOPMENT AND PEDIATRICS: -Describe pediatric infectious keratitis patterns at a tertiary referral centers -Discuss current patching protocols for pediatric patients with ambylopia -Describe the global motion perception deficits in amblyopia VISUAL PERCEPTION: -Describe new insights in the development of amblyopia -Recognize the role of voice processing in developmental prosopagnosia -Describe the effects of hemianopia on experimental studies of alexia DISEASE MECHANISMS: -Recognize the use of Zebrafish as a model system for genetic disorders -Describe the role of drusen component in inflammatory changes in a rodent model for macular degeneration ANTERIOR SEGMENT: -Describe findings on anterior-segment OCT that could predict IOP lower post-cataract surgery patients -Understand the utility of collagen cross-linking in progressive crosslinking in children -Describe the use of scleral tunnels in the use of Ahmed glaucoma valves RETINA: -Describe the role of OCT angiography in the imaging of foveal capillaries -Describe the effect of vinpocetine on outer retinal inflammation in an animal model -Understand the role of membrane attack complex in the pathogenesis of macular degeneration NEW THERAPIES: -Describe the use of gene therapy for the treatment of X-linked retinoschisis -Recognize novel molecular approaches for transplanting photoreceptor precursor cells -Understand the potential role of laser in the treatment of persistent subretinal fluid post-retinal detachment repair surgery Twenty-five percent of the time will be devoted to discussions of the clinical relevance of the presentations led by designated authorities, allowing the audience to decide how this research could impact their practice. By merging basic science and clinical research, the program will be of interest to ophthalmologists, ophthalmologists-in-training, basic scientists and allied health professionals. Course Planning Committee Orson Moritz, PhD - Associate Professor Paul Mackenzie, MD, PhD – Associate Professor Simon Warner, MD, FRCSC - Clinical Professor Ipek Oruc, PhD – Assistant Professor Zaid Mammo, MD – Resident Judges Jacque Duncan, MD TBA Nicholas Swindale, Ph.D Sponsors We gratefully acknowledge and thank our sponsors for their support of this educational conference: PLATINUM Alcon Canada Inc. Bayer Inc. GOLD Allergan Inc. AMO (Canada) BRONZE Pfizer Canada Inc Novartis Inc.
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