Evaluation of postoperative visual function based on the preoperative inner layer structure in the epiretinal membrane.

PURPOSE

To evaluate the postoperative visual function using a preoperative epiretinal membrane (ERM) classification based on the status of the inner layer structure.

METHODS

We assessed 62 eyes, one from each patient undergoing vitrectomy with internal limiting membrane (ILM) peeling for unilateral ERM. The inclusion criteria were as follows: (1) the presence of idiopathic ERM based on optical coherence tomography and a healthy contralateral eye, (2) successful surgery after 25- or 27-gauge transconjunctival 3-port pars plana vitrectomy with ILM peeling, and (3) a minimum follow-up period of 12 months. We included patients with preoperative ERM morphology with no disruption of the inner retinal layer in group A (37 eyes) and those with disruption in group B (25 eyes) and compared the visual acuity, central visual-field sensitivity (CVFS) measured using the Humphrey field analyzer 10-2 program, and detection rate of micro-scotoma (< 10 dB) at baseline and 12 months postoperatively between the groups.

RESULTS

Visual acuity at 12 months showed greater improvement in group A than in group B (P = .03). There was no significant difference in CVFS at baseline; however, that of the nasal area was substantially lower after surgery in group B than in group A (P = .02). The 12-month postoperative detection rate of micro-scotoma was significantly higher in group B than in group A (P = .002).

CONCLUSION

ERM that has preoperatively disrupted the inner layer poses the risks of CVFS reduction and micro-scotoma formation after vitrectomy. Evaluating the inner layer could be an important prognostic factor in determining retinal function in ERM.