Background: With a large portion of older adults living longer, the number of individuals diagnosed with low vision is increasing. The use of optical coherence tomography/scanning laser ophthalmoscope (OCT/SLO) to diagnose retinal disease has become common place in the last 10 years, yet currently there are no OCT/SLO databases for pathological vision. Our aim is to develop a clinical database of individuals who have drusen (i.e., lipid deposits found under the retina), or have been diagnosed with age-related macular degeneration (AMD), with information as to how the structure of the diseased retina changes over time, as well as measures of visual and cognitive functional performance.

Methods: Fundus photographs and retinal scans will be taken using the same model of optos OCT/SLO located in three test sites (MAB-Mackay Rehabilitation Centre, School of Optometry Clinic at the University of Montreal, and the Lighthouse Institute, New York, USA). For each individual entry in the database, demographic and diagnosis information will be available. All OCT/SLO images will be graded according to the Age-related Eye Disease Study standard, in addition to number and size of drusen, severity of geographic atrophy, severity of pigment mottling and presence of choroidal neovascularization. Retinal topography and Raster scans from the OCT/SLO will provide a cross-sectional look at affected retinas. Fixation stability will be recorded using the SLO function, and present four different tasks that are designed to reproduce typical tasks of daily vision, with each task lasting for 10 seconds. The tasks are cross fixation, face recognition, visual search, and reading. These tasks in addition to the retinal scans will be used to determine the eccentricity of a preferred retinal locus from the anatomical fovea, and can be used as an outcome measure for clinical interventions in visually impaired patients.

Results: The database will be available to professors training eye-care practitioners and rehabilitation specialists as a teaching tool. Students will be able to familiarize themselves with the retina and a variety of AMD-related pathologies before they start working with patients. The database will also be accessible by researchers interested in studying AMD from basic science to epidemiology, to investigate how drusen and AMD impact visual and cognitive functional performance.

Conclusions: The common infrastructure is easily accessible to all VHRN members on request. The database will also be accessible online in 2018 (see http://cvl.concordia.ca for more information).

Background: Congenital hereditary endothelial dystrophy (CHED) is characterized by blindness at birth or in early infancy resulting from bilateral corneal opacification, and is linked to mutation in the Slc4a11 gene. A Slc4a11 knockout (KO) mouse, generated by gene deletion (Vithana et al. Nat Genet 2006), was acquired in order to study this disease. To confirm the phenotype of this Slc4a11 KO mouse model as a function of age, using the wild type (WT) mouse as a control.

Methods: Genotyping was performed by PCR (REDExtract-N-AmpTM Tissue PCR Kit, Sigma-Aldrich, Oakville, ON). Slc4a11 WT and KO mice populations aged from 5 to 50 weeks were studied (n=5 animals per age group; 5-year age intervals). Slit lamp examination, anterior segment-ocular coherence tomography (OCT930SR; Thorlabs, Inc., Newton, NJ), corneal endothelial cell staining, and scanning (SEM) and transmission (TEM) electron microscopy were used to assess the morphological and cellular differences between the two groups. The expression of basolateral membrane transporter NaBC1 within the corneal endothelium was also assessed using immunohistochemistry.

Results: Diffuse and progressive corneal opacification was observed at the slit lamp in the Slc4a11 KO mice, starting at 10 weeks. The central corneal thickness (CCT) also increased progressively as a function of time. In comparison, Slc4a11 WT corneas remained clear over the entire study period. Early TEM results showed vacuole degeneration of the corneal endothelium in the 15-week KO mouse, which was not seen in the same age WT mouse.

Conclusions: The corneal phenotype of this Slc4a11 KO mouse is representative of the clinical manifestations of CHED in human subjects, confirming the usefulness of this model for studying pathophysiology and therapeutic alternatives for Slc4a11-associated corneal dystrophies.

Abstract: Optical coherence tomography (OCT) angiography is a new non-invasive imaging modality which is providing clinicians with an alternative to traditional dye-based angiography. The images are obtained using the concept of motion contrast and provide a quicker safer way to image the retinal and choroidal circulation. Not only are there practical aspects to support its integration but new insights are being made into the path; hysiology of various retinal choroidal diseases due to its ability to provide a 3-dimensional view of the vasculature which can be segmented in many ways to focus in on the circulation of a given anatomic region of the retina. We are currently in the phase of integration of this new technology into our practices.

Background: The aim of this project is to develop a new standardized and cost-efficient method to compare optical coherence tomography (OCT) scans to their corresponding paraffin embedded histopathology sections in post-mortem eyes. This correlation will clarify the interpretation of OCT images, and it will also enable direct immunohistochemical characterization of features observed on OCT.

Methods: Study design: donor eyes were obtained from two separate eye banks. In order to minimize post-mortem change like retinal detachment and vitreous opacification, the eyes were fixed in a previously tested fixative solution. Time between death and fixation has been kept under 6 hours. Methods: Using a customized imaging device, nine post-mortem eyes were imaged with a SD-OCT machine. Subsequently, an 8mm trephine was used to isolate a portion of the posterior pole including the macular area and the optic nerve head for histopathological analysis. Paraffin embedded cross sections of the retina were obtained and visually compared to each OCT image (b-scans).

Results: To facilitate the correlation of OCT images to their histopathological sections, three principle aspects were controlled during tissue processing: rotation, tilt and location. Using markings as well as anatomical landmarks, serial histopathological sections in an orientation comparable to OCT b-scans were obtained, thereby facilitating image pairing.

Conclusions: Compared to other well-established methods using resin and electron microscopy, our standardized Methods allowed us to successfully compare OCT b-scans to serial retinal cross sections of a wider macular area at a lower cost. Our novel approach allows us to translate features observed on OCT images into well-established histopathological images, providing the clinician with additional tools to obtain difficult diagnoses with more confidence.

Abstract: Pediatric neuro-ophthalmology is a subspecialty within neuro-ophthalmology. Pediatric neuro-ophthalmic diseases must be considered separate from their adult counterparts, due to the distinctive nature of the examination, clinical presentations, and management choices. This manuscript will highlight four common pediatric neuro-ophthalmic disorders by describing common clinical presentations, recommended management, and highlighting recent developments. Diseases discussed include pediatric idiopathic intracranial hypertension (IIH), pseudopapilledema, optic neuritis (ON) and optic pathway gliomas (OPG). The demographics, diagnosis and management of common pediatric neuro-ophthalmic disease require a working knowledge of the current research presented herein. Special attention should be placed on the differences between pediatric and adult entities such that children can be appropriately diagnosed and treated.

Abstract: Pathologic myopia is the major cause of the loss of the best-corrected visual acuity (BCVA) worldwide, especially in East Asian countries. The loss of BCVA is caused by the development of myopic macula patchy, myopic traction macula patchy, and myopic optic neuropathy (or glaucoma). The development of such vision-threatening complications is caused by eye deformity, characterized by a formation of posterior staphyloma. The recent advance in ocular imaging has greatly facilitated the clarification of pathologies and pathogenesis of pathological myopia and myopia-related complications. These technologies include ultra-wide field fundus imaging, swept-source optical coherence tomography, and 3D MRI. In addition, the new treatments such as anti-VEGF therapies for myopic choroid all neovascularization have improved the outcome of the patients. Swept-source OCT showed that some of the lesions of myopic maculopathy were not simply chorioretinal atrophy but were Bruch’s membrane holes. Features of myopic traction maculopathy have been analyzed extensively by using OCT. The understanding the pathophysiology of complications of pathologic myopia is considered useful for better management of this blinding eye disease.

Keywords: Diabetic macular edema (DME); diabetic macular oedema (DMO); anti-vascular endothelial growth factor (anti-VEGF); laser photocoagulation; randomised clinical trials (RCTs); retina; diabetic retinopathy

Abstract: To describe the current aging population in China and globally, especially as it applies to age-related macular degeneration (AMD). To review the current standards of care for treating both wet (exudative) eAMD and dry (atrophic) aAMD. And to introduce a model for experimentation that is based on the Age-Related Eye Disease Study (AREDS) using eye bank tissue. A literature search that outlines current aging populations, standards of clinical treatment as defined by large, multicenter, randomized clinical trials that present level-I data with a low risk for bias. An experimental model system of AMD is presented that enables scientific analysis of AMD pathogenesis by applying grading criteria from the AREDS to human eye bank eyes. Analysis includes proteomic, cellular, and functional genomics. The standard of care for the treatment of eAMD is currently defined by the use of several anti-vascular endothelial growth (anti-VEGF) agents alone or in combination with photodynamic therapy. Monotherapy treatment intervals may be monthly, as needed, or by using a treat-and-extend (TAE) protocol. There are no proven therapies for aAMD. AMD that is phenotypically defined at AREDS level 3, should be managed with the use of anti-oxidant vitamins, lutein/zeaxanthin and zinc (AREDS-2 formulation). By understanding the multiple etiologies in the pathogenesis of AMD (i.e., oxidative stress, inflammation, and genetics), the use of human eye bank tissues graded according to the Minnesota Grading System (MGS) will enable future insights into the pathogenesis of AMD. Initial AMD management is with lifestyle modification such as avoiding smoking, eating a healthy diet and using appropriate vitamin supplements (AREDS-2). For eAMD, anti-VEGF therapies using either pro re nata (PRN) or TAE protocols are recommended, with photodynamic therapy in appropriate cases. New cellular information will direct future, potential therapies and these will originate from experimental models, such as the proposed eye bank model using the MGS, that leverages the prospective AREDS database.