Evaluation of Retinal Parameters in Patients With Epiretinal Membrane After Vitrectomy

Official title

Evaluation of Morphological and Functional Changes in Eyes With Epiretinal Membrane After Vitrectomy

Overview

The goal of this interventional study is to assess the dynamics of structural and functional retinal changes in eyes with epiretinal membrane (ERM) after pars plana vitrectomy (PPV). Other study objectives include: * Identification of preoperative prognostic factors associated with better postoperative outcomes. * Evaluation of the utility of advanced, highly specialized retinal function testing as diagnostic-prognostic tools in patients after ERM surgery. * Definition of updated qualification criteria and surgical indications for vitrectomy in patients with ERM. Researchers will compare a laser-treated group (additional subthreshold micropulse yellow laser (577 nm) at 1 month post-PPV) with a nonlaser group (no additional laser) to see whether early postoperative subtreshold micropulse laser therapy (SMLT) affects selected functional and morphometric retinal parameters after ERM peeling. This prospective, randomized, controlled, single-center study includes 100 pseudophakic patients scheduled for surgical ERM removal. Eligibility requires a visually significant ERM with metamorphopsia and/or reduced best-corrected visual acuity. Participants are classified preoperatively by OCT-based Govetto staging and randomized 1:1 to either the laser-treated group or the non-laser (control) group. All patients undergo standard 25-gauge PPV with ERM peeling, followed by ILM peeling and SF₆ gas tamponade, performed by a single experienced vitreoretinal surgeon. Follow-up visits occur preoperatively, and at 1 and 4 months postoperatively; SMLT is performed at 1 month in the laser arm. Baseline questionnaire captures metamorphopsia presence (yes/no) and duration (\<6, 6-12, \>12 months). Assessments include: * best corrected visual acuity (BCVA) \[Snellen and ETDRS charts\] * enhanced depth imaging optical coherence tomography (EDI-OCT) \[retinal thickness in the nine Early Treatment Diabetic Retinopathy Study (ETDRS) subfields (μm); total retinal volume (mm³); subfoveal choroidal thickness (μm); choroidal area (mm²)\] * OCT angiography (OCTA) \[foveal avascular zone (FAZ) area in both the superficial (SVC) and deep vascular complexes (DVC) (mm²)\] * multifocal electroretinography (mfERG) \[P1-wave retinal response density (nV/deg²) in rings R1-R6; P1-wave implicit (peak) time in rings R1-R6 (ms)\] * microperimetry (average threshold (dB); fixation stability P1/P2; fixation variability via 63% and 95% bivariate contour ellipse area (BCEA)\] * wide-field fundus imaging Statistical analyses will be performed at a significance level of p\<0.05, using appropriate parametric or nonparametric methods selected based on data distribution and measurement scale.

Interventions

• Device Subtreshold micropulse laser therapy
  Laser-treated group will receive additional subthreshold micropulse laser therapy (SMLT) 1 month after pars plana vitrectomy (PPV), using a 577 nm solid-state yellow diode laser applied to the macular area (thirty 5 × 5 spot sizes of 160 µm, zero-spot spacing, including the fovea; fixed power 250 mW; exposure time 200 ms; micropulse mode, 5% duty cycle). Control group (nonlaser group) will not receive additional laser treatment.
• Procedure Pars plana vitrectomy
  Both groups will undergo pars plana vitrectomy (PPV) with epiretinal membrane (ERM) and internal limiting membrane (ILM) peeling prior to allocation to study arms.

Primary outcome measures

• Change in BCVA from 1 month post-PPV (pre-laser) to 4 months post-PPV. [Time frame: 1 month (pre-laser) and 4 months postoperatively.]

Secondary outcome measures (10)

• Change in mfERG P1-wave retinal response density in rings R1-R6. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in mfERG P1-wave implicit time in rings R1-R6. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in average threshold on microperymetry. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in fixation stability P1 and P2 on microperymetry. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in fixation variability on microperymetry. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in retinal thickness on EDI-OCT. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in total retinal volume on EDI-OCT. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in subfoveal choroidal thickness on EDI-OCT. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in choroidal area on EDI-OCT. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]
• Change in FAZ area in the SVC and DVC on OCTA. [Time frame: Baseline (pre-op), 1 month, and 4 months post-op.]

Eligibility criteria

Inclusion criteria

• Epiretinal membrane (ERM) - either associated with metamorphopsia or causing a marked reduction in best corrected visual acuity
• Pseudophakia

Exclusion criteria

• Coexisting ocular or retinal diseases other than ERM
• Evidence of ocular inflammation or any active intraocular inflammatory process

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

Poland · 1 center

• First Department of Ophthalmology, Pomeranian Medical University — Szczecin

Identifiers

NCT: NCT07165626 · KB-006/25/2024

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗