Changes to the Retina Following Anti-VEGF Treatments for Diabetic Macular Edema

Study Overview
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Brief Summary
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anti-VEGF therapy is an established method to control leakage and abnormal growth of retinal blood vessels. Questions on the long-term effect on the retina, intraocular pressure and on the overall retinal perfusion from these treatments remain to be answered. The purpose of the study was to evaluate changes in the retina following anti-VEGF treatment over time, using structural and functional diagnostic tests.

Detailed Description
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Diabetic retinopathy (DR) causes changes in the capillaries that nourish the retina. Two treatments clinically used for DR are laser photocoagulation to reduce the angiogenic drive by knocking off metabolically active retina and anti-VEGF drugs for diabetic macular edema (DME). DME affects approximately 2.5% of the nearly 2.4 million Canadians with diabetes, or approximately 60,000 Canadians, making it a major cause of adult-onset vision loss. DME occurs when blood vessels in the retina of diabetic patients become leaky resulting in unwanted fluid accumulation in the center of vision known as the macula. If not treated, this can lead to blindness. Originally used in the treatment of age-related macular degeneration (AMD), anti-VEGF drugs are increasingly used to control leakage and abnormal growth of retinal blood vessels. Numerous questions have emerged following the usage of anti-VEGF medications in the eye such as their long-term effects of these drugs on intraocular pressure and on the overall retinal perfusion. By recruiting DR patients requiring anti-VEGF treatment for DME, this study will answer whether long-term usage of anti-VEGF will result in structural and functional changes to the retina.

Official Title
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A Clinico-Pathological Study of the Structural and Functional Changes to the Retina Following Anti-VEGF Treatments for Diabetic Macular Edema

Conditions
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Diabetic Macular Edema

Intervention / Treatment
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* Drug: Ranibizumab Ophthalmic


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: DME patients Require anti-VEGF injections in at least one eye Exclusion Criteria: Advanced lens opacity or cataract that could affect diagnostic testing Prior retinal treatment (PRP, focal laser or surgery within 6 months of participation)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Ranibizumab Ophthalmic<br>DME consults requiring anti-VEGF treatment | Drug: Ranibizumab Ophthalmic<br>* Ranibizumab (trade name Lucentis among others) is a monoclonal antibody fragment (Fab) created from the same parent mouse antibody as bevacizumab. It is an anti-angiogenic that has been approved to treat the wet type of age-related macular degeneration (AMD, also ARMD), a common form of age-related vision loss and diabetic macular edema (DME).<br>* Other names: Lucentis;|
| Control<br>DME consults not requiring anti-VEGF | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effects of anti-VEGF drugs on intraocular pressure (mmHg) |  | 2 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effects of anti-VEGF drugs on macular thickness (um) |  | 2 year |