Correlation Between the Visual Acuity & the OCT Pattern of Macular Edema Secondary to RVO

Study Overview
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Brief Summary
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Correlation between changes observed in OCT and VA in patients with retinal vein occlusion whether the patient's VA improves when macular edema improves in OCT or not ??

Detailed Description
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Central retinal vein occlusion (CRVO) is a common retinal vascular disorder. Clinically, CRVO presents with variable visual loss; fundus may show retinal hemorrhages, dilated tortuous retinal veins, cotton-wool spots, macular edIn view of the devastating complications associated with the severe form of CRVO, number of classifications were described. All of classifications take into account the area of retinal capillary nonperfusion and development of neovascular complications. CRVO can be divided into 2 clinical types, ischemic and nonischemic. In addition, a number of patients may have an intermediate presentation with variable clinical course. On initial presentation, it may be difficult to classify a given patient, since CRVO may change with time. A number of clinical and ancillary investigative factors are taken into account for classifying CRVO: Nonischemic CRVO is milder form of disease. It may present with good vision, few retinal hemorrhages and cotton-wool spots, no relative afferent pupillary defect, and good perfusion to the retina. Nonischemic CRVO may resolve fully with good visual outcome or may progress to the ischemic type. Ischemic CRVO is the severe form of the disease. CRVO may present initially as the ischemic type, or it may progress from nonischemic. Usually, ischemic CRVO presents with severe visual loss, extensive retinal hemorrhages and cotton-wool spots, presence of relative afferent pupillary defect, poor perfusion to retina, and presence of severe electroretinographic changes. In addition, patients may end up with neovascular glaucoma and a painful blind eye.

Official Title
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Correlation Between the Visual Acuity and the OCT Pattern of Macular Edema Secondary to Retinal Vein Occlusion

Conditions
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Retinal Vein Occlusion

Intervention / Treatment
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* Device: OCT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with macular edema related to vein occlusion . Patient's Age above 18 years old . Patients able to sit on OCT device . Exclusion Criteria: Significant cataract . Media opacities as vitreous haemorrhage . patients with macular edema related to CRVO treated by laser photocoagulation . patients with glaucoma . Patients with chronic uveitis.

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 |
| --- | --- |
| Patients with macular edema due to RVO<br>assessment of visual acuity using Landolt chart and follow up of macular edema using OCT | Device: OCT<br>* Assessment of macular edema secondary to retinal vein occlusion usin optical coherence tomography and its correlation with visual acuity<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Macular edema assessment | Macular edema assessed by OCT in microns | 5 minutes | 
| Visual acuity assessment | Visual acuity assessment through Landolt chart | 5 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Causes of non improvement of visual acuity in patients with resolving macular edema | To detect causes of visual non improvement with visual acuity measured through Landolt chart in patients with resolving macular edema measured by OCT device in microns | 5 minutes |