Abstract
Purpose:
Assessment of the outer and the inner retina using optical coherence tomography and the correlation with visual acuity in idiopathic epiretinal membrane
Methods:
The medical records of 60 eyes were reviewed retrospectively to collect visual acuity (VA), ganglion cell complex thickness (GCT) and photoreceptor reflectivity (PR) at baseline, 3 and 6 months after surgery. GCT was adjusted to compensate centripetal traction by calculating relative thickness to macular thickness (MT, adjusted GCT = GCT/MT). PR was adjusted to remove shadowing effects from the inner retina. Reflectivity of the photoreceptor layer and the retinal pigment epithelium (RR) was measured, and the ratio was calculated (adjusted PR = measured PR/RR).
Results:
Preoperative PR were correlated with VA at 6 months after surgery (R=-0.273, p=0.038), but not with VA at baseline (R=-0.204, p=0.124) and 3 months (R=-0.197, p=0.139). Preoperative GCT was not evaluated due to segmentation errors by ERM. At 3 months, only GCT had significant correlation with VA (R=-0.352, p=0.007). At 6 months, both GCT (R=-0.324, p=0.013) and RR (R=-0.377, p=0.004) were significantly correlated with VA.
Conclusions:
In idiopathic ERM, the status of the inner retina had a significant correlation with postoperative VA. The impact of the outer retina on visual function seemed overestimated due to shadowing effect from the inner retina. In early postoperative period, the inner retina was a dominant factor for visual function than the outer retina. The outer retina was correlated with VA in late postoperative period. The postoperative improvement of VA would be related with recovery of the inner retina.
Keywords: 550 imaging/image analysis: clinical