Abstract
Purpose :
Metamorphopsia is an invalidating symptom poorly correlated with the morphology of epiretinal membrane (ERM). The goal of this study was to describe a characteristic OCT sign which correlates both with the pathoanatomy of the Henle fiber layer (HFL) and with the degree of metamorphopsia.
Methods :
Retrospective evaluation of clinical charts, structural and en-face OCTs performed in a consecutive cohort of patients diagnosed with ERMs.
Results :
Eighty eyes of 76 patients were included. Sixty patients underwent surgery with pars plana vitrectomy, ERM and ILM peel with a centrifugal peeling technique. M-charts were available in 32 patients. Two patterns of epiretinal traction were identified with en-face OCT: concentric and eccentric (Figure 1, A and B). Thirty-one out of 80 eyes (38.75%) presented with eccentric traction, while 49 out of 80 eyes (61.25%) presented with concentric traction. In concentric ERM (Figure 1, A), the lines of traction converge toward a focal point centered at the fovea, while in eccentric ERM (Figure 1,B) the lines of traction have an heterogenous morphology. At the HFL, concentric ERM was characterized by a symmetrical fingerprint sign, visible as concentric circles, similar to what observed in healthy eyes (Figure 1, C). Differently, in eccentric ERM such OCT sign was irregular (Figure 1,D). Concentric ERMs were characterized by lower metamorphopsia scores, vertical and horizontal, both preoperatively and postoperatively at week 1, month 1 and month 3 (p<0.001). Both in concentric and eccentric ERM, the fingerprint sign faded out over the follow up period (Figure 2, A and B).
Conclusions :
The fingerprint sign in ERM may be the result of centripetal displacement of the outer retina, with narrowing of the vertical segment of the Müller cells below the outer plexiform layer. The morphology of the fingerprint sign had a significant correlation with metamorphopsia scores and may be used as a predictor for postoperative vision quality. Centripetal peeling may help in maintaining the normal microanatomy of the central fovea.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.