title: Optic disk size and optic disk-to-fovea distance in preterm and full-term infants.
abstract: OBJECTIVE
  Few studies have assessed optic disk and retinal morphology in infants. Here the optic disk and optic disk-to-fovea distance were measured in preterm and full-term infants in vivo.
  
  
  METHODS
  Optic disk (OD) dimensions and the center-to-center distance between the OD and the macula were measured using digital imaging in infants undergoing routine ophthalmic examinations. Postmenstrual age of the mother at the time of examination ranged from 32 to 50 weeks. From each image, the OD-to-fovea distance (ODF) and the OD height (ODH) and OD width (ODW) were measured.
  
  
  RESULTS
  In 51 retinal images from 51 infants, mean +/- SD values obtained were 4.4 +/- 0.4 mm (ODF), 1.41 +/- 0.1 9 mm (ODH), and 1.05 +/- 0.13 mm (ODW). These dimensions did not change significantly over the age range studied. The mean value for the ratio between ODF and mean OD diameter (ODF/DD) was 3.76.
  
  
  CONCLUSIONS
  Results of this in vivo study suggest that though the optic nerve head diameter increases by more than 50%, only limited growth occurs at the highly organized area of the posterior pole from birth to adulthood. This study discusses the finding of a large-angle kappa in infants and the use of a disk macula/disk diameter ratio in the diagnosis of optic nerve hypoplasia.
authors.affiliation: Department of Ophthalmology, Western Eye Hospital, London, United Kingdom. drdjdesilva@yahoo.co.uk
authors.forename: Don Julian
authors.initials: DJ
authors.lastname: De Silva
authors.forename: Ken D
authors.initials: KD
authors.lastname: Cocker
authors.forename: Gordon
authors.initials: G
authors.lastname: Lau
authors.forename: Simon T
authors.initials: ST
authors.lastname: Clay
authors.forename: Alistair R
authors.initials: AR
authors.lastname: Fielder
authors.forename: Merrick J
authors.initials: MJ
authors.lastname: Moseley
mesh_terms: D001724:Birth Weight; D001837:Body Weights and Measures; D005260:Female; D005584:Fovea Centralis / Q000033:anatomy & histology*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D009898:Optic Disk / Q000033:anatomy & histology*; D047929:Term Birth