
Fractalkine, a CX3C Chemokine, Act as a Mediator of Ocular Angiogenesis
Proliferative Diabetic RetinopathyAngiogenesisFractalkine (FKN) is a chemoattractant and adhesion molecule for leukocytes. Angiogenic effect of FKN also has been reported. We investigate FKN-mediated angiogenesis in ocular angiogenic disorders.

Validation of a Predictive Model to Estimate the Risk of Conversion to Clinically Significant Macular...
Diabetic RetinopathyThis project aims to validate a predictive model of diabetic retinopathy progression to clinically significant macular edema (CSME) needing photocoagulation and/or vision loss. The Coimbra Predictive Model (CPM), based on retinal thickness, microaneurysms number, HbA1C and LDL levels, established on a set of 52 diabetic patients, will be tested on a population of 400 patients/eyes to be enrolled into the study. These patients will perform 2 visits at 6-month interval (V0 and V6) to classify each patient into one of the 3 previously established phenotypes. Two years after (V24) patients will be reexamined. The occurrence of end-points, achieved by the patients, are expected to validate our predictive model.

Genetics and Markers of Degenerative and Inflammatory Eye Diseases
Diabetic RetinopathyAge-Related Macular Degeneration (AMD)1 moreThis study will identify genes that are associated with inflammation or degeneration of the retina (membrane lining the back of the eye that relays vision signals to the brain). It is thought that many retinal conditions are due to an altered immune system and are based on how the person s genes function and communicate. People 4 years of age or older who have a retinal condition such as uveitis, age-related macular degeneration or diabetic retinopathy may be eligible for this study. Healthy volunteers and healthy people who have a family member with one of these conditions are also eligible. Patients with inherited retinal degeneration are excluded. Participants undergo the following tests and procedures: Eye examination to assess visual acuity (eye chart test) and eye pressure, and to examine the pupils, lenses, retina and eye movements. Photographs of the inside of the eye may also be taken. The pupils are dilated with drops for this examination. Blood draw for genetic testing. Participants may also undergo one or more of the following tests: Optical coherence tomography. This is a type of photograph of the back of the eye to measure thickness of the retina. Fluorescein angiography and indocyanine green angiography. Pictures of the eye s blood vessels are taken using either a fluorescein or indocyanine green dye. The dye is injected into a vein in an arm and travels to the blood vessels in the eyes. A camera takes pictures of the dye as it flows through the blood vessels. Electroretinogram (ERG) to measure retinal function. The patient sits in a dark room for 30 minutes with his or her eyes patched. Then, a small metal disk electrode is taped to the forehead, the eye patches are removed, the surface of the eye is numbed with eye drops, and contact lenses are placed on the eyes. The patient then watches flashing lights. The contact lenses sense small electrical signals generated by the retina when the light flashes....

Intravitreal Bevacizumab Pretreatment for Reducing Preretinal Hemorrhage in Diabetic Vitrectomy...
Proliferative Diabetic RetinopathyTreatment of severe proliferative diabetic retinopathy (PDR) may require the use of silicone oil for long-term retinal tamponade to prevent recurrent retinal detachment. Massive bleeding during surgery before proper release of traction and peri-silicone oil proliferation after surgery were major causes of surgical failure. The likelihood of reproliferation rises in the presence of significant preretinal blood. It is therefore crucial to reduce intraoperative and postoperative preretinal hemorrhage in complicated diabetic vitrectomy with silicone oil infusion. Intravitreal avastin has been noted to induce rapid regression of retinal and iris neovascularization in proliferative diabetic retinopathy. Further, presurgical administration of intravitreal avastin may reduce intraoperative bleeding during membrane dissection in PDR with traction retinal detachment. The pretreatment of avastin may be particularly beneficial in the treatment of severe active fibrovascular proliferation by decreasing the severity of intraoperative and postoperative intraocular hemorrhage, leading to better surgical outcome and early visual rehabilitation. We conduct a prospective study to evaluate the effect of avastin on the severity of intra- and post-operative bleeding, frequency of recurrent bleeding, and anatomical and functional outcome in eyes with severe active PDR undergoing vitrectomy with silicone oil infusion.

Long Term Follow-Up of Diabetic Retinopathy
BlindnessCataract3 moreThe efficacy of laser photocoagulation treatment for diabetic retinopathy has been demonstrated by several National Eye Institute (NEI) sponsored clinical trials. The Diabetic Retinopathy Study (DRS) demonstrated that scatter photocoagulation reduces the risk of blindness from diabetic retinopathy. The Early Treatment Diabetic Retinopathy Study (ETDRS) extended these findings by providing information on when to initiate scatter photocoagulation and by demonstrating that focal treatment was effective in treating macula edema. The Krypton Argon Regression Neovascularization Study (KARNS) showed that scatter photocoagulation with krypton red laser was just as safe and effective as the argon blue-green laser in the treatment of proliferative diabetic retinopathy. Unfortunately, there is little data on the long term effects of photocoagulation on visual function. The first objective of this study is to assess the long term effects of photocoagulation for diabetic retinopathy. A second objective is to provide additional information on the risk of progression of cataracts in persons with diabetes. All patients previously treated with laser photocoagulation (focal and/or scatter) are eligible to participate in this long term study. The first priority will be given to patients who participated in the ETDRS and KARNS because of the wealth of information available regarding the details of their treatment and course after treatment. Study evaluations will include a standard ophthalmic examination, fluorescein angiography, lens and fundus photography.

Validation Study of RETINA-AI Galaxy™ v2.0, an Automated Diabetic Retinopathy Screening Device
DiabetesDiabetic Retinopathy2 moreDiabetes affects over 37 million Americans and over 530 million people globally. Each diabetic patient needs at least one retinal exam per year starting immediately at the time of diagnosis if they have Type II diabetes (and starting at 5th year after disease onset if they have Type I diabetes). However, majority of diabetic patients do not get their eye exam due to multiple prohibitive factors such as cost, transportation, difficulty of taking time off from work, and inconvenience, amongst others. As a result, diabetes is the most common cause of visual impairment and blindness in working age adults in the United States and globally. Early detection via effective screening can prevent diabetes-related blindness. However, there are multiple barriers to screening. This prompted the development of RETINA-AI Galaxy™ v2.0, an automated Software as a Medical Device that screens for diabetic retinopathy in the primary care setting. This observational study was designed to validate the safety and efficacy of the RETINA-AI Galaxy™ Software-as-a-Medical-Device.

Automated Diagnostic Test for Diabetic Retinopathy in Brazilian Mass Screening
Diabetic RetinopathyIn Brazil 10% of the adult population has diabetes. Of these, 39.0% are undiagnosed, at risk for developing complications such as diabetic retinopathy (DR). Due to the increasing prevalence of diabetes and high percentage of patients with uncontrolled disease, cost-effective tools are needed with focused attention on diabetes prevention and management in the current health system. The automatic retinopathy detection can enlarge the screening, reducing the workload and costs compared to manual image graders.

Assessment of EyeArt as an Automated Diabetic Retinopathy Screening Tool
Diabetic RetinopathyDiabetic Eye Problems1 moreMore than 29 million people in the US are living with diabetes, many of whom will develop diabetic retinopathy (DR) or diabetic macular edema (DME) collectively known as diabetic eye disease (DED), the leading cause of vision loss and blindness in working-age adults. Annual eye screening is recommended for all diabetic patients since vision loss can be prevented with laser photocoagulation and anti-VEGF treatment if DR is diagnosed in its early stages. Currently, the number of clinical personnel trained for DR screening is orders of magnitude smaller than that needed to screen the large, growing diabetic population. Therefore, to meet this large unmet need for DR screening, a fully-automated computerized DR screening system is necessary. EyeArt is an automated screening device designed automatically analyze color fundus photographs of diabetic patients to identify patients with referable or vision threatening DED. This study is designed to assess the safety and efficacy of EyeArt.

Restoration of Retinal Vascular Responses in Type 1 Diabetic Patients
Diabetic RetinopathyDiabetic retinopathy is the leading cause of blindness in the developed world. The causes of the disease are poorly understood. One of the earliest changes that occur in the retinas of diabetic patients, well before overt retinopathy is observed, is a reduction in light-evoked increases in blood flow in retinal vessels. The loss of this vascular response may lead to retinal hypoxia and it has been suggested that hypoxia could be a principal cause of diabetic retinopathy. The long-term goals of this project are to determine whether decreased blood flow in diabetic patients and the resulting retinal hypoxia contributes to the development of diabetic retinopathy and whether restoration of normal blood flow in diabetic patients slows or prevents the development of retinopathy.

Comparison of Changes of Inflammatory Proteins in Aqueous Humour of Subjects Treated With Avastin...
Proliferative Diabetic Retinopathy (PDR)PDR is a leading cause of irreversible vision loss in North America. This disease is caused by the growth of abnormal blood vessels in the retina. These abnormal blood vessels can bleed inside the eye, causing a vitreous hemorrhage (VH). Sometimes when patients have this bleeding, a surgery called vitrectomy is required to remove the blood from within the eye. In order to reduce complications during the surgery, most retina surgeons will inject Avastin into the eye a few days before the surgery. Avastin (bevacizumab) is currently not approved by Health Canada to treat any ocular disease. Lucentis (ranibizumab) is approved by Health Canada as a treatment for age-related macular degeneration, diabetic macular edema, and retinal venous occlusive disease. While Avastin is not approved by Health Canada for the treatment of these diseases, the majority of retina specialists around the world are now using Avastin "off-label" to treat these diseases. That is because Avastin and Lucentis both tend to work equally well in these disease, but Avastin is significantly cheaper. While Avastin and Lucentis are generally regarded to be equal, there may be some differences between these two drugs that have not been discovered. The aim of this study is to look for these differences. Previous research by the investigators in this study has shown that injecting Avastin into eyes causes increased inflammatory proteins to develop inside the eye. This increase in these proteins was related to complications that developed after the vitrectomy surgery. Lucentis may be associated with less of an increase in inflammatory proteins (and less complications). The aim of this study will be to compare Avastin and Lucentis with respect to how they affect inflammatory proteins in the eye, as well as the rate of complications during surgery. Study participants will be divided into two arms ("groups") of 30 subjects. Subjects will receive Avastin or Lucentis a few days before vitrectomy surgery. The assignment will be random and the study is double-masked. Masking is done so that the investigators can clearly determine any differences between the 2 drugs.