Preoperative Vision, Gender, and Operation Time Predict Visual Improvement After Epiretinal Membrane Vitrectomy: A Retrospective Study

Abstract

Background: To evaluate the efficacy of micro-incision vitrectomy surgery using a non-contact wide-angle viewing system for fovea-attached type epiretinal membrane, and to report the factors influencing the outcome.

Methods: A retrospective, comparative case series that included 50 patients with fovea-attached type epiretinal membrane who received micro-incision vitrectomy surgery using a non-contact wide-angle viewing system.

Results: All patients were followed-up for a minimum of 12 months. Seven cases were classified as group 1A (mainly outer retinal thickening), 17 were group 1B (more tenting of outer retina and distorted inner retina), and 26 were group 1C (prominent inner retina thickening and inward tenting of outer retina). Outcome measures included operation time, recurrent rate, postoperative BCVA, and CRT. The mean operative time was 26.2 minutes. The mean change of BCVA (LogMAR) was -0.43 (p< 0.001). The mean change of CRT was 135.3 μm (p< 0.001). The mean change of CRT was significantly higher in group 1C. Worse preoperative BCVA, male gender, and longer operative time can predict better postoperative BCVA found by multivariate logistic regression and multiple regression models.

Conclusion: Significant improvement in BCVA and CRT is noted after micro-incision vitrectomy surgery to operate fovea-attached type epiretinal membranes. Worse preoperative BCVA, male, and longer operation time could predict better improvement. These findings may assist surgeons in better evaluating the potential of this method to help their patients with epiretinal membranes.

Keywords: fovea-attached type epiretinal membrane; gender; micro-incision vitrectomy surgery; operation time; preoperative vision; wide-angle viewing system.

Figure 1

Fovea-attached type ERM can be classified as Group 1A: ERM with mainly outer retinal thickening and maintained a nearly normal configuration, Group 1B: more exaggerated tenting of outer retinal layer in the fovea area and inner retina distorted by centripetal and anteroposterior forces due to ERM, and group 1C: prominent inner retina thickening with inward tenting of the outer retinal reflectivity in the foveal area. Group 1A and 1C are globally adherent to the retina, while Group 1B is focally adherent.

Figure 2

(A) Comparison of proportion of male gender between groups with different visual outcomes. (B) Comparison of preoperative BCVA (LogMAR) between groups with different visual outcomes.