Epiretinal membrane surgery: anatomic and functional outcomes

To study the influence of anatomic preoperative characteristics (based on the parameter, foveal central thickness, measured by optical coherence tomography) and functional characteristics (based on the parameter, best corrected visual acuity, [BCVA]) on functional recovery after epiretinal membrane (ERM) surgery.

A total of 88 eyes (of 86 patients), on whom a vitrectomy due to ERM was performed during a 3 years period were reviewed in this longitudinal, prospective study. An analysis was made of, ERM aetiology, BCVA, presence or absence of metamorphopsia, lens status, and central foveal thickness. Data relating to surgery and local complications, changes in BCVA, and changes in foveal central thickness were collected during the follow-up period.

An improvement was in observed in BCVA in 82%, as well as a decrease in foveal thickness in 79% of the eyes which underwent surgery, both of these being statistically significant (P<.01). However, most of the patients showed different grades of oedema and/or macular thickening in the postoperative period. A significant correlation was found between preoperative and postoperative BCVA (P=.001), and also between preoperative and postoperative central foveal thickness (P=.004), but not between BCVA and foveal thickness.

There is functional recovery in terms of BCVA in more than 80% of the patients after ERM surgery. Most of the eyes showed persistent macular thickening, but this did not seem to have influenced the final BCVA. The best determinant of postoperative functional recovery (postoperative visual acuity) is, in our experience, the preoperative BCVA, and not the macular thickness.