Impact of Axial Length on Visual Outcomes and OCT Findings in Epiretinal Membrane: A Retrospective Study.

Background

Axial elongation may influence the structural characteristics and surgical prognosis of epiretinal membrane (ERM), but its impact across different axial length (AL) categories remains unclear.

Methods

We retrospectively analyzed 557 eyes from 515 patients with ERM who underwent vitrectomy and were followed for at least 6 months. Eyes were stratified by AL into normal to mild myopia (NM; <26 mm), high myopia (HM; ≥26 to <28 mm), and extreme high myopia (EHM; ≥28 mm). Clinical variables included age, AL, and pre- and postoperative best-corrected visual acuity (BCVA). OCT parameters assessed included inner and outer retinal cystoid lesions, epiretinal proliferation (EP), and ellipsoid zone (EZ) disruption.

Results

Postoperative BCVA significantly improved in the NM and HM groups (p < 0.001) but not in the EHM group (p = 0.091). Although preoperative BCVA was comparable among groups, postoperative BCVA was significantly better in the HM group (-0.02 ± 0.17 logMAR) compared with the NM (0.03 ± 0.20 logMAR) and EHM (0.21 ± 0.43 logMAR) groups (p < 0.05). Outer retinal cystoid lesions were significantly more frequent in the EHM group (p < 0.05), whereas the prevalence of EZ disruption, inner retinal cystoid lesions, and EP did not differ significantly among groups.

Conclusions

Eyes with ERM and extreme high myopia exhibited limited postoperative visual improvement and a higher prevalence of outer retinal cystoid lesions, suggesting that axial elongation may adversely affect surgical prognosis.