Short-term Anterior Segment Changes After Pars Plana Vitrectomy (PPV) and Silicone Oil (SO) Tamponade, Anterior Segment OCT (AS-OCT) Study.

Study Overview
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Brief Summary
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The purpose of our study is to utilize AS-OCT to analyze the anterior segment morphological changes in the early postoperative period of patients who will undergo PPV with silicone oil injection.

Detailed Description
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Type of the study: A prospective comparative study. Study Setting: Assiut university hospital. Study subjects: Inclusion criteria: Patients suffering from different vitreo-retinal disorders (rhegmatogenous retinal detachment, diabetic vitreous hemorrhage, diabetic tractional retinal detachment) with either preserved crystalline lens or previous cataract surgery (at least 3 months prior to PPV) will be recruited Exclusion criteria: Patient with previous history of ocular trauma, co-existing glaucoma, co-existing anterior uveitis, complicated cataract surgery, IOL-related complications, previous vitreo-retinal surgery, visually significant cataract (necessitating combined phacoemulsification with PPV and SO) and significant corneal opacity will be excluded. If any significant post-PPV complication develops, patient will be excluded from the study. Sample Size Calculation: Thirty eyes (30 patients) will undergo PPV with SO tamponade and AS-OCT analysis prior to surgery and 1 week post-operatively to achieve study power of 80% with 0.05 significance. 4 -Study tools (in detail, e.g., lab methods, instruments, steps, chemicals, …): All participants underwent best-corrected visual acuity (BCVA) by Snellen's chart, Slit lamp assessment of the anterior segment, dilated fundus examination, intra-ocular pressure (IOP) measurement by calibrated Goldmann Applanation Tonometer (GAT). Baseline Ophthalmic ultrasound and Axial length measurement will be obtained. Anterior segment OCT (AS-OCT) protocol All eyes will be examined by AS-OCT (Nidek RS-3000 Advance, Tokyo, Japan) 1-2 days prior to vitreo-retinal surgery and one week after surgery by single experienced physician. Poor fixation or poor image signal (less than 3/10) will exclude the patient from the study. Anterior segment OCT (AS-OCT) parameters The following anterior segment parameters will be evaluated; central and peripheral anterior chamber depth (cACD, pACD), anterior chamber angle (ACA) and central corneal thickness (CCT). 5 -Research outcome measures: Primary (main): Mean change in central anterior chamber depth after PPV with SO tamponade. Secondary (subsidiary): Mean change in peripheral anterior chamber depth, mean change in anterior chamber angle and mean change anterior chamber angle entry area.

Official Title
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Short-term Anterior Segment Changes After Pars Plana Vitrectomy (PPV) and Silicone Oil (SO) Tamponade, Anterior Segment OCT (AS-OCT) Study.

Conditions
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ASOCT Changes After Vitrectomy and Silicone Oil Injection

Intervention / Treatment
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* Procedure: vitrectomy and silicone oil injection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients suffering from different vitreo-retinal disorders (rhegmatogenous retinal detachment, diabetic vitreous hemorrhage, diabetic tractional retinal detachment) with either preserved crystalline lens or previous cataract surgery (at least 3 months prior to PPV) will be recruited Exclusion Criteria: Patient with previous history of ocular trauma, co-existing glaucoma, co-existing anterior uveitis, complicated cataract surgery, IOL-related complications, previous vitreo-retinal surgery, visually significant cataract (necessitating combined phacoemulsification with PPV and SO) and significant corneal opacity will be excluded. If any significant post-PPV complication develops, patient will be excluded from the study.
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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Design Details

Primary Purpose: Screening
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Double


Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: vitrectomy and silicone oil injection|Parsplana vitrectomy and silicone oil injection|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| central anterior chamber depth | Mean change in central anterior chamber depth after PPV with SO tamponade. | 1 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| peripheral anterior chamber depth | Mean change in peripheral anterior chamber depth | 1 week | 
| anterior chamber angle | mean change in anterior chamber angle | 1 week | 
| anterior chamber angle entry area | mean change anterior chamber angle entry area | 1 week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ASOCT, vitrectomy, silicone oil injection