Prospective Retinal and Optic Nerve Vitrectomy Evaluation (PROVE) Study

Study Overview
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Brief Summary
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Since the introduction of vitrectomy in 1971, this procedure has become the third most frequently performed ophthalmic surgery. Approximately 225,000 vitrectomies are performed annually in the United States and indications continue to expand. Known long-term complications of vitrectomy are relatively few and include retinal detachment and cataract formation. Although much has been written in the literature concerning acute rises in intraocular pressure (IOP) in the immediate postoperative period, there is surprisingly little information on long term IOP outcomes after vitrectomy. A recent report by Chang given at the LXII (62) Edward Jackson Memorial Lecture hypothesized a causal relationship between vitrectomy and open-angle glaucoma (OAG) via oxidative stress exacerbated by removal of the crystalline lens. A second report by Luk and colleagues reported similar conclusions in a modified cohort. Both studies, were retrospective in nature and did not perform baseline evaluations to exclude pre-existing glaucoma. Furthermore neither study accounted for natural history. Finally, our analysis has not reproduced similar results. The primary purpose of this study is to analyze the full spectrum of optic nerve and macular changes between vitrectomized study eyes and their non-vitrectomized fellow eyes to control for natural history. Baseline evaluations will include examination by fellowship trained retina and glaucoma specialists, fundus photography, autofluorescence, optical coherence tomography (macula and optic nerve) and automated visual field testing. At 3 month then annually for 5 years after vitrectomy surgery, the cohort will undergo similar evaluation.

Official Title
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A Prospective Analysis of Nerve Fiber Layer and Macular Changes After Pars Plana Vitrectomy

Conditions
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Glaucoma, Macular Pucker, Macula Hole, Vitreomacular Traction, Vitreous Opacities or Hemorrhage

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Able to consent and comply for the duration of the study and imaging studies Media clarity sufficient for imaging studies No previous treatment or surgery that might confound study results in the study or fellow eye Pars plana vitrectomy (PPV) indicated for epiretinal membrane (ERM), macular hole (MH), vitreo-macular traction (VMT), and vitreous hemorrhage (VH) Exclusion Criteria: Unable to consent and/or comply for the duration of the study and imaging studies History of the following conditions: Glaucoma or associated conditions, visual field defects, uveitis, age-related macular degeneration (ARMD), prior PPV for retinal detachment, retained lens or dislocated intraocular lens Contralateral eye status post PPV or with advanced eye disease serious enough to warrant future PPV - Contralateral eye with condition that may result in choroidal neovascular membrane

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Nerve fiber layer and macular changes after vitrectomy | To determine the incidence of nerve fiber layer (NFL) and macular changes after pars plana vitrectomy, characterize their extent and quality, and determine pre-disposing risk factors. | 3 month and annually for 5 years after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual field defects | To characterize long-term functional consequences of NFL or macular changes with regards to peripheral and central visual field defects after PPV. | 3 month and annually for 5 years after surgery | 
| Open-angle glaucoma | To determine the incidence of elevated intraocular pressure and open-angle glaucoma following vitrectomy. Enrolled patients will be screened at baseline to exclude pre-existing glaucoma and post-operative glaucoma screenings will be performed by fellowship trained glaucoma specialist. | 3 month and annually for 5 years after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitrectomy, Glaucoma, Macula, Optic nerve, Ocular Coherence Tomography