title: Effects of Diabetic Macular Edema on Repeatability of Retinal Nerve Fiber Layer Thickness Measurements at the Macular and Peripapillary Area Using Swept-Source Optical Coherence Tomography.
abstract: To investigate the repeatability of macular and peripapillary retinal nerve fiber layer (RNFL) thickness measurements made using swept-source optical coherence tomography (SS-OCT) and automated segmentation. Measurements were made in non-diabetic controls and in patients with diabetic retinopathy (DR) with or without diabetic macular edema (DME).
  
  
  
  A total of 131 eyes of 131 participants were included. Fifty-one eyes with DR had no DME (DME[-]), 45 eyes with DR had DME (DME[+]), and 35 eyes were healthy. Measurements of RNFL and full retinal thickness were simultaneously obtained with SS-OCT in the peripapillary area and in the nine Early Treatment Diabetic Retinopathy Study (ETDRS) subfields using the wide three-dimensional mode. All measurements were made twice on the same day by a single examiner to test intra-observer repeatability. Intraclass correlation coefficients (ICCs) and coefficients of repeatability were examined to evaluate repeatability.
  
  
  
  Average macular and temporal peripapillary RNFL thickness values were greater in the DME[+] group (36.4 ± 13.2 and 83.8 ± 19.4 µm, respectively) than in the control (27.4 ± 3.5 and 73.5 ± 11.4 µm, respectively) and DME[-] (27.9 ± 3.4 µm and 70.3 ± 11.3 µm, respectively) groups (both P < 0.001). The ICCs of average macular (control: 0.982, DME[-]: 0.913, and DME[+]: 0.970) and peripapillary (control: 0.972, DME[-]: 0.973, and DME[+]: 0.958) RNFL thickness measurements indicated good repeatability in all three study groups.
  
  
  
  Although the ICCs of average RNFL thickness measurements were relatively lower in eyes with DR than in healthy controls, the intra-observer repeatability of SS-OCT RNFL and full retinal thickness measurements is sufficiently reliable for them to be clinically useful.
authors.affiliation: a Department of Ophthalmology , Ulsan University Hospital, University of Ulsan, College of Medicine , Ulsan , Republic of Korea.
authors.forename: Jung Kee
authors.initials: JK
authors.lastname: Min
authors.affiliation: a Department of Ophthalmology , Ulsan University Hospital, University of Ulsan, College of Medicine , Ulsan , Republic of Korea.
authors.forename: Seunghwan
authors.initials: S
authors.lastname: Lee
authors.affiliation: a Department of Ophthalmology , Ulsan University Hospital, University of Ulsan, College of Medicine , Ulsan , Republic of Korea.
authors.forename: Ju Sung
authors.initials: JS
authors.lastname: Kim
authors.affiliation: a Department of Ophthalmology , Ulsan University Hospital, University of Ulsan, College of Medicine , Ulsan , Republic of Korea.
authors.forename: Je Moon
authors.initials: JM
authors.lastname: Woo
authors.affiliation: a Department of Ophthalmology , Ulsan University Hospital, University of Ulsan, College of Medicine , Ulsan , Republic of Korea.
authors.forename: Hyun Seung
authors.initials: HS
authors.lastname: Yang
mesh_terms: D003930:Diabetic Retinopathy / Q000150:complications / Q000175:diagnosis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008266:Macula Lutea / Q000473:pathology*; D008269:Macular Edema / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology*; D015203:Reproducibility of Results; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence / Q000379:methods / Q000706:statistics & numerical data*; D014792:Visual Acuity
keywords: Diabetic macular edema; diabetic retinopathy; repeatability; retinal nerve fiber layer; swept-source optical coherence tomography