Three-dimensional analysis of morphologic changes and visual outcomes in diabetic macular edema

To investigate the association of retinal fluid volume with the visual and anatomic outcomes of patients with diabetic macular edema (DME) after treatment with bevacizumab.

Retrospective observational study.

We retrospectively analyzed 65 eyes of 58 DME patients treated with bevacizumab. The volumes of the inner intraretinal fluid (IRF) in the inner nuclear layer (INL), outer IRF in the outer plexiform layer (OPL)/outer nuclear layer (ONL), and subretinal fluid (SRF) were calculated. The correlations between the baseline fluid volumes and best-corrected visual acuity (BCVA), area of disorganization of the retinal inner layers (DRIL), disrupted external limiting membrane (ELM), and disrupted ellipsoid zone (EZ) at 12 months after treatment were assessed.

The baseline volume of the inner IRF correlated with poor BCVA at the final visit (r = 0.52, P < .001) whereas the baseline volume of the outer IRF and SRF volume did not show a significant correlation with BCVA at the final visit (P = .07 and P = .61, respectively). The improvement in BCVA correlated with the reduction in the baseline volume of the inner IRF and outer IRF (r = 0.25, P = .04 and r = 0.36, P = .003), but not with the SRF volume (P = .59). The baseline volume of the inner IRF correlated positively with the area of DRIL and the disrupted ELM at the final visit (r = 0.56, P < .001 and r = 0.25, P = .04, respectively). Such relationship remained in each quadrant of the macula (P < .005 for all quadrants).

The baseline volume of the inner IRF correlated with a poor visual outcome, an increased DRIL area, and a more disrupted ELM area in patients with DME after treatment with bevacizumab.