Abstract
Purpose:
To determine differences in reflectance and thickness of the retinal layers between normal eyes and eyes before and after epiretinal membrane (ERM) removal using spectral domain optical coherence tomography (SD-OCT) images.
Methods:
Thirty-four eyes with idiopathic ERM and 12 normal fellow eyes were imaged preoperatively and postoperatively using SD-OCT. SD-OCT images were segmented and analyzed for thickness and reflectance using a custom-built algorithm. Differences in reflectivity and thickness between the control, preoperative ERM patients, and postoperative ERM patients were analyzed. Additionally, the correlation of retinal layer thickness and reflectivity with change in BCVA was assessed.
Results:
There was an improvement (p = 0.001) in postoperative BCVA (logMAR, mean: 0.31, SD: 0.19) compared to preoperative BCVA (logMAR, mean: 0.54, SD: 0.31). There were differences in preoperative ERM OCT thickness of the internal limiting membrane to outer plexiform layer (ILM to OPL), outer nuclear layer (ONL), and external limiting membrance (ELM) and both postoperative (p=0.000, p=0.046, and p=0.020, respectively) and normal OCTs (p=0.000, p=0.001, and p=0.001, respectively). Postoperative ERM OCT thickness of ILM to OPL and PRL were thicker than normal OCTs (p=0.001 and p=0.001). There were differences in preoperative ERM OCT total reflectance of the ILM to OPL and ELM and both postoperative (p=0.009 and p=0.032, respectively) and normal (p=0.000 and p=0.001, respectively) OCTs. Postoperative ERM OCT total reflectance of the ILM to OPL was higher than normal OCTs (p=0.039). Overall, BCVA was correlated with thickness of the ILM to OPL (p=0.000), ONL (p=0.002), and ELM (p=0.042) and total reflectance of the ILM to OPL (p=0.045), ELM (p=0.000), PRL (p=0.000), and RPE (p=0.022). Final BCVA was correlated with the preoperative OCT ILM to OPL thickness (p=0.039) and reflectance (0.036). Change in BCVA was correlated with preoperative OCT ONL thickness (p=0.001) and total reflectance of the ONL (p=0.038), PRL (p=0.000), and RPE (p=0.010).
Conclusions:
ERM-peeling surgery resulted in significantly improved BCVA. Quantitative changes are seen in thickness and total reflectance of the retinal layers among the pre- and post-operative ERM and normal OCTs. Thickness and total reflectance of the different retinal layers are correlated with BCVA overall, final BCVA, and change in BCVA.
Keywords: 585 macula/fovea •
762 vitreoretinal surgery