Changes in Ciliary Body Thickness in Patients With Diabetic Macular Edema After Vitrectomy

Study Overview
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Brief Summary
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The purpose of this study is to determine whether ciliary body thickness increased in the presence of diabetic macular edema and whether it changed after pars plana vitrectomy.

Detailed Description
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A diabetic macular edema group consisted of diabetic patients who underwent PPV for diffuse diabetic macular edema. A epiretinal membrane group, a surgical control group, consisted of non-diabetic patients with epiretinal membrane who underwent pars plana vitrectomy. A healthy control was also included for the comparison of preoperative ciliary body thickness. Ciliary body thickness was measured using ultrasound biomicroscopy, and central macular thickness was determined using optical coherence tomography. The visual outcome, ciliary body thickness, and central macular thickness were compared between groups before and 1, 2, and 4 months after pars plana vitrectomy and the correlations between the central macular thickness and ciliary body thickness and best corrected visual acuity were determined.

Conditions
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Diabetic Macular Edema

Intervention / Treatment
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* Procedure: Pars Plana Vitrectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria for diabetic macular edema group: Diabetic macular edema with preoperative central macular thickness > 300 μm on optical coherence tomography Macular edema that was not associated with an epiretinal membrane or traction membrane No combined traction retinal detachment or vitreous hemorrhage No signs of ocular inflammatory disease on preoperative examination Phakic eye An axial length between 22.0 mm and 25.0 mm Exclusion Criteria for diabetic macular edema group: Patients with uveitis, inflammatory connective tissue disorders or a history of previous ocular surgery Long-term application of topical medication, a history of intravitreal steroid or anti-VEGF injection within 3 months before vitrectomy Inclusion Criteria for epiretinal membrane group: Non-diabetic patients with an epiretinal membrane who were scheduled for vitrectomy No ocular or systemic disease other than epiretinal membrane Inclusion Criteria for healthy group: No diabetes No ocular disease other than cataract

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 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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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Diabetic Macular Edema Group<br> | Procedure: Pars Plana Vitrectomy<br>* 25-gauge three-port pars plana vitrectomy<br>|
| Active Comparator: Epiretinal Membrane Group<br> | Procedure: Pars Plana Vitrectomy<br>* 25-gauge three-port pars plana vitrectomy<br>|
| No Intervention: Healthy Control<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ciliary body thickness | ciliary body thickness was determined using ultrasound biomicroscopy | up to four months after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| central macular thickness | central macular thickness was determined using optical coherence tomography | up to four months after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Diabetic Macular Edema, Ciliary Body, Ultrasound Biomicroscopy, Vitrectomy