title: Reproducibility and repeatability of foveal avascular zone measurements in healthy subjects by optical coherence tomography angiography.
abstract: OBJECTIVE
  To assess the reproducibility and repeatability of foveal avascular zone (FAZ) area measurements using optical coherence tomography angiography (OCT-A) in healthy subjects.
  
  
  METHODS
  Sixty healthy volunteers (60 eyes) were subjected to FAZ area measurements by means of high speed and high resolution spectral-domain OCT (SD-OCT) XR Avanti with the split-spectrum amplitude decorrelation angiography algorithm by two experienced examiners in two different sessions.
  
  
  RESULTS
  The mean±SD age of the subjects was 28.9±7.6 years. Overall FAZ areas measured by the first and second observer were 0.251±0.096 mm(2) and 0.252±0.096 mm(2), respectively. Within subjects, the coefficients of variations were 1.83% (95% CI 1.51% to 2.20%) and 1.86% (95% CI 1.33% to 2.43%) for the first and second observers, respectively. The coefficient of repeatability average measurements of FAZ area were 0.015 mm(2) and 0.013 mm(2) for the first and second observers, respectively. The intraclass correlation coefficient values were 0.997 (95% CI 0.995 to 0.998) and 0.998 (95% CI 0.996 to 0.999) for the first and second observers, respectively. Inter- and intraobserver concordance correlation coefficients ranged from 0.994 (95% CI 0.990 to 0.977) to 0.999 (95% CI 0.997 to 0.999) and from 0.997 (95% CI 0.995 to 0.998) to 0.996 (95% CI 0.994 to 0.998), respectively.
  
  
  CONCLUSIONS
  FAZ area measurements by means of OCT-A showed excellent reproducibility and repeatability in healthy eyes. OCT-A is a non-invasive diagnostic method, and its reliability makes it an interesting potential diagnostic tool for disease detection and follow-up in retinal pathologies involving foveal microcirculation.
authors.affiliation: Ophthalmology Clinic, Department of Medicine and Aging Sciences, High-Tech National Center in Ophthalmology, University "G. d'Annunzio" Chieti-Pescara, Chieti, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Carpineto
authors.affiliation: Ophthalmology Clinic, Department of Neurological and Visual Science, University of Verona, Verona, Italy.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Mastropasqua
authors.affiliation: Ophthalmology Clinic, Department of Neurological and Visual Science, University of Verona, Verona, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Marchini
authors.affiliation: Ophthalmology Clinic, Department of Medicine and Aging Sciences, High-Tech National Center in Ophthalmology, University "G. d'Annunzio" Chieti-Pescara, Chieti, Italy.
authors.forename: Lisa
authors.initials: L
authors.lastname: Toto
authors.affiliation: Department of Experimental and Clinical Sciences, Laboratory of Biostatistics, University "G. d'Annunzio" Chieti-Pescara, Chieti, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Di Nicola
authors.affiliation: Ophthalmology Clinic, Department of Medicine and Aging Sciences, High-Tech National Center in Ophthalmology, University "G. d'Annunzio" Chieti-Pescara, Chieti, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Di Antonio
mesh_terms: D000328:Adult; D000792:Angiography; D005260:Female; D005584:Fovea Centralis / Q000033:anatomy & histology* / Q000098:blood supply*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012171:Retinal Vessels / Q000033:anatomy & histology*; D041623:Tomography, Optical Coherence; D055815:Young Adult
keywords: Anatomy; Angiogenesis; Macula; Retina