title: Intraretinal changes in the presence of epiretinal traction.
abstract: BACKGROUND
  To determine the correlation between the area of morphological changes on the macular surface, the depth of intraretinal changes and the best-corrected visual acuity (BCVA) in patients with idiopathic epiretinal membrane.
  
  
  METHODS
  In this prospective cross-sectional study, 38 patients underwent BCVA testing with a Snellen eye chart. The depth of traction, photoreceptor outer segment layer (PROS) thickness, central macular thickness (CMT) and presence of intraretinal cysts were measured using the Avanti RTVue XR and 3D Widefield Enface OCT instruments. Enface sections were performed at the inner limiting membrane (ILM) line level (ILM offset). Patients were categorized into two groups: in group 1 (n = 21), the depth of traction was within 90 μm from the ILM, and in group 2 (n = 17) it was beyond 90 μm from the ILM. The main outcome measure was the correlation between area of epiretinal traction and BCVA according to the depth of traction.
  
  
  RESULTS
  In group 1, the depth of traction was 55.15 ± 14.28 μm, the area of traction was 38.95 ± 13.63 mm2, PROS thickness was 51.20 ± 7.23 μm, and CMT was 362.65 ± 41.08 μm. In group 2, the depth of traction was 112.24 ± 10.89 μm, the area of traction was 25.18 ± 4.07 mm2, PROS thickness was 50.24 ± 9.01 μm, and mean CMT was 534.29 ± 126.81 μm. Statistically significant differences in depth of traction, area of traction and CMT were found between the two groups (P < 0.001). The relationship between structure and function between the area of traction and BCVA was better explained in group 2 (r = 0.814, P < 0.001).
  
  
  CONCLUSIONS
  We found that intraretinal changes were induced by the ERM, and varied according to the depth of traction measured with en face analysis. In the case of traction deeper than 90 μm, we found a significant correlation between the inner area of the epiretinal traction and BCVA. We believe that retinal stress induced by epiretinal traction is better characterized by combining information provided by sagittal and transverse OCT scans, thus defining its prognostic significance in ERM.
authors.affiliation: Dipartimento di Neuroscienze, Scienze Riproduttive ed Odontostomatologiche, University Federico II, Via Pansini 5, 80131, Naples, Italy. romanomario@email.it.
authors.forename: Mario R
authors.initials: MR
authors.lastname: Romano
authors.affiliation: Dipartimento di Neuroscienze, Scienze Riproduttive ed Odontostomatologiche, University Federico II, Via Pansini 5, 80131, Naples, Italy.
authors.forename: Gilda
authors.initials: G
authors.lastname: Cennamo
authors.affiliation: Dipartimento di Neuroscienze, Scienze Riproduttive ed Odontostomatologiche, University Federico II, Via Pansini 5, 80131, Naples, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Amoroso
authors.affiliation: Dipartimento di Neuroscienze, Scienze Riproduttive ed Odontostomatologiche, University Federico II, Via Pansini 5, 80131, Naples, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Montorio
authors.affiliation: Humanitas Research Hospital, Via Manzoni 56, Rozzano, MI, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Castellani
authors.affiliation: Eye Clinic, University of Catania, Catania, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Reibaldi
authors.affiliation: Dipartimento di Neuroscienze, Scienze Riproduttive ed Odontostomatologiche, University Federico II, Via Pansini 5, 80131, Naples, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cennamo
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D019773:Epiretinal Membrane / Q000175:diagnosis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008266:Macula Lutea / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D055214:Retinal Photoreceptor Cell Outer Segment / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000379:methods*; D014792:Visual Acuity
keywords: En face OCT; Epiretinal membrane; Intraretinal cysts; Tangential traction