Optical Coherence Tomography Angiography (OCTA) Changes in Patients With Epiretinal Membranes (ERM) With and Without Peeling of the Internal Limiting Membrane (ILM)
Study Details
Study Description
Brief Summary
Main objective
The objective is to compare two surgical options in vitrectomies for epiretinal membranes using parameters of optical coherence tomography angiography.
Background
State of the art treatment for epiretinal membranes consists of pars plana vitrectomy, staining of the epiretinal membrane with a blue colouring dye and epiretinal membrane peeling. The vitrectomized space is filled with fluid (balanced salt solution) during the procedure and the fluid can optionally be replaced with air as a final step. After ERM peeling (but before the selection of the tamponade), the internal limiting membrane (the innermost layer of the retina) is either peeled as well or left untouched and the question which method should be preferred has been a hot topic in recent years. The investigators want to investigate possible effects of the used method (peeling vs. nonpeeling) on retinal perfusion parameters represented by OCTA. Two epiretinal membrane patient groups will therefore be formed: The first group's (group 1) ILM will be peeled, the second group's (group 2) ILM will not be peeled. After recruitement, patients will therefore be electronically randomized to one of the two groups. The groups will then be compared by the means of OCTA.
Study design
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Since there are no previous data on our research question, this investigation is defined as a pilot study.
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40 patients with epiretinal membranes will be included. This appears to be a reasonable number given the incidence of epiretinal membranes. Previous studies that compared peeling versus nonpeeling in ERM used similar sample sizes. The detectable effect size was calculated at d = 0.91. We intend to complete this pilot study within 9 months.
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Randomization will be performed using electronic randomization. 20 patients each will be randomized to either group 1 or group 2.
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Both eyes in each patient will be imaged.
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No treatment decisions will be made based on OCTA findings. Treatment decisions will be made according to the clinic's standard of care.
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Three follow-up visits specific to the study are needed. These visits will be scheduled one week, one month and three months after surgery. All other preoperative and follow-up visits will be decided by the treating physician and follow the clinic standard of care.
Examinations
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Distance visual acuity using ETDRS (Early Treatment Diabetic Retinopathy Study) standard at 4 meters as per clinic standard of care.
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Tonometry as per clinic standard of care.
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Slit-lamp evaluation as per clinic standard of care.
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Arterial blood pressure.
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Axial eye length.
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Heidelberg Spectralis conventional OCT.
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The following 2 AngioVue scans will be taken:
- One 3mm x 3mm, 304 x 304 A-scan OCTA of the macula B. One 6mm x 6mm, 304 x 304 A-scan OCTA of the macula
Hypothesis
The null hypothesis of our investigation indicates that there are no statistically significant differences in OCTA perfusion parameters based on the used option.
The alternative hypothesis states that there are statistically significant differences in OCTA perfusion parameters based on the used option.
Primary Objective
To demonstrate possible differences in OCTA perfusion parameters based on the used option.
Secondary Objectives
To assess the feasibility of the AngioVue optical coherence tomography angiography system in evaluating subtle changes in the retinal perfusion of patients with epiretinal membranes.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: ILM nonpeeling
|
Procedure: ILM nonpeeling
ILM is not peeled after ERM removal
|
| Other: ILM peeling
|
Procedure: ILM peeling
ILM is peeled after ERM removal
|
Outcome Measures
Primary Outcome Measures
- Superficial capillary plexus foveal avascular zone area [3 months]
Superficial capillary plexus foveal avascular zone area (SCP FAZ) change (preoperative to postoperative). The SCP FAZ represents the area of the macula where blood vessels are not seen in OCTA under physiologic conditions. It has previously been reported that the FAZ narrows during ERM development and enlarges after ERM removal.
Eligibility Criteria
Criteria
Inclusion Criteria:
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Patient must be able and willing to give informed consent.
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Patient must be over 18 and below 100 years of age.
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Patient must not have any significant media opacity which interferes with the examination.
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Patient must have an epiretinal membrane requiring surgery.
Exclusion Criteria:
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Unwilling or unable to provide informed consent
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Under 18 or over 100 years of age
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Significant media opacities
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Systemic pathologies making an examination difficult or cumbersome to the patient
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Secondary epiretinal membranes
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Bilateral epiretinal membranes
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Macular holes
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Lamellar holes
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Pseudo holes
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Glaucoma
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Diabetes
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Anisometropia > 2 diopters
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High myopia (spherical equivalent > 6 diopters and/or axial length > 26 mm
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Other retinal or ophthalmic pathologies except moderate cataract
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OCTA scan signal strength < 50
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Low image quality
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Failure of automatic layer segmentation
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Medical University Graz | Graz | Styria | Austria | 8010 |
Sponsors and Collaborators
- Medical University of Graz
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 32-443 ex 19/20