title: Racial variation in optic nerve head parameters quantified in healthy newborns by handheld spectral domain optical coherence tomography.
abstract: OBJECTIVE
  To characterize optic nerve head (ONH) morphology and parameters, including vertical disk diameter, vertical cup diameter, and vertical cup/disk ratio in healthy, full-term newborns using a handheld spectral domain optical coherence tomography (SD-OCT) device.
  
  
  METHODS
  In this prospective observational case series, healthy white, black, and Hispanic full-term newborns delivered at the Duke Birthing Center between August 2010 and May 2011 underwent dilated fundus examination and SD-OCT imaging of the optic nerve in each eye. OCT parameters were calculated and compared for each group of infants.
  
  
  RESULTS
  A total of 58 consecutive newborns of white (n = 22), black (n = 15) and Hispanic (n = 21) ethnicity were included. Mean vertical disk diameter in white, black, and Hispanic newborns was 1.29 ± 0.15 mm (standard deviation), 1.38 ± 0.14 mm, and 1.38 ± 0.14 mm, respectively (white versus Hispanic, P = 0.02; white versus black, P = 0.07). Mean vertical cup diameter in white, black, and Hispanic newborns was 0.44 ± 0.15 mm, 0.56 ± 0.23 mm, and 0.46 ± 0.30 mm, respectively (white versus black, P = 0.03). Mean vertical cup/disk ratio was 0.34 ± 0.10 for white, 0.40 ± 0.17 for black, and 0.33 ± 0.20 for Hispanic newborns (P = 0.07 for white versus black).
  
  
  CONCLUSIONS
  Handheld SD-OCT is an effective means of imaging the ONH in newborns. Racial differences in cup/disk ratio are present at birth. These data may serve as the beginning of a normative dataset for characterizing development of the ONH as well as for comparison to the neonatal ONH in disease states.
authors.affiliation: Department of Ophthalmology, Duke Eye Center, Durham, North Carolina.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Allingham
authors.forename: Michelle T
authors.initials: MT
authors.lastname: Cabrera
authors.forename: Rachelle V
authors.initials: RV
authors.lastname: O'Connell
authors.forename: Ramiro S
authors.initials: RS
authors.lastname: Maldonado
authors.forename: Du
authors.initials: D
authors.lastname: Tran-Viet
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: Toth
authors.forename: Sharon F
authors.initials: SF
authors.lastname: Freedman
authors.forename: Mays A
authors.initials: MA
authors.lastname: El-Dairi
mesh_terms: D044383:Black People; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009887:Ophthalmoscopy / Q000379:methods*; D009898:Optic Disk / Q000033:anatomy & histology*; D019095:Point-of-Care Systems; D011446:Prospective Studies; D041623:Tomography, Optical Coherence / Q000295:instrumentation*; D044465:White People