title: Volume Averaging of Spectral-Domain Optical Coherence Tomography Impacts Retinal Segmentation in Children.
abstract: OBJECTIVE
  To determine the influence of volume averaging on retinal layer thickness measures acquired with spectral-domain optical coherence tomography (SD-OCT) in children.
  
  
  METHODS
  Macular SD-OCT images were acquired using three different volume settings (i.e., 1, 3, and 9 volumes) in children enrolled in a prospective OCT study. Total retinal thickness and five inner layers were measured around an Early Treatment Diabetic Retinopathy Scale (ETDRS) grid using beta version automated segmentation software for the Spectralis. The magnitude of manual segmentation required to correct the automated segmentation was classified as either minor (<12 lines adjusted), moderate (>12 and <25 lines adjusted), severe (>26 and <48 lines adjusted), or fail (>48 lines adjusted or could not adjust due to poor image quality). The frequency of each edit classification was assessed for each volume setting. Thickness, paired difference, and 95% limits of agreement of each anatomic quadrant were compared across volume density.
  
  
  RESULTS
  Seventy-five subjects (median age 11.8 years, range 4.3-18.5 years) contributed 75 eyes. Less than 5% of the 9- and 3-volume scans required more than minor manual segmentation corrections, compared with 71% of 1-volume scans. The inner (3 mm) region demonstrated similar measures across all layers, regardless of volume number. The 1-volume scans demonstrated greater variability of the retinal nerve fiber layer (RNLF) thickness, compared with the other volumes in the outer (6 mm) region.
  
  
  CONCLUSIONS
  In children, volume averaging of SD-OCT acquisitions reduce retinal layer segmentation errors.
  
  
  CONCLUSIONS
  This study highlights the importance of volume averaging when acquiring macula volumes intended for multilayer segmentation.
authors: The Gilbert Family Neurofibromatosis Institute, Washington, DC, USA.
authors: Carmelina
authors: C
authors: Trimboli-Heidler
authors: The George Washington School of Medicine, Washington, DC, USA.
authors: Kelly
authors: K
authors: Vogt
authors: The Gilbert Family Neurofibromatosis Institute, Washington, DC, USA ; Center for Neuroscience and Behavior, Children's National Health System, Washington, DC, USA.
authors: Robert A
authors: RA
authors: Avery
keywords: OCT; segmentation; volume