Purpose: To evaluate whether an index based on hole configuration can be used to predict visual outcome in eyes with idiopathic macular holes.
Design: Prospective interventional case series.
Methods: Thirty-five eyes of 32 patients with idiopathic stage 2 or 3 macular hole were enrolled in this study. The best-corrected visual acuity (BCVA), cross-sectional image of the macular hole by optical coherence tomography (OCT), and retinal thickness in the central (<1000 microm), inner (1000 to 2220 microm), and outer ring areas (2220 to 3450 microm) as defined by the OCT retinal mapping program were evaluated preoperatively and at 1, 3, 6, and 12 months postoperatively. The change in retinal thickness of the inner ring area at the 6-month postoperative period was used to evaluate the degree of preoperative retinal deformation. The macular hole index (MHI) (ratio of hole height to base diameter of hole) was calculated and correlated with minimum diameter of hole, base diameter of hole, the postoperative decrease in macular thickness, and the postoperative BCVA. The postoperative BCVA was further evaluated in two patient-matched groups.
Results: Retinal thickness values in the inner ring area were decreased at the 1-month postoperative period. MHI significantly correlated with the postoperative decrease in macular thickness in the inner ring area at 6 months (correlation coefficient = -0.632, P = .030, Spearman analysis) and with the postoperative BCVA (P = .013, multiple regression analysis). Postoperative BCVA in the MHI >/=0.5 group was better than that in the MHI <0.5 group (P = .032, Mann-Whitney test).
Conclusions: The MHI is a ratio easily calculated from OCT transverse images of the macular area. The MHI represents the preoperative configuration of a macular hole and is a prognostic factor for visual outcome.