title: Retinal straylight as a function of age and ocular biometry in healthy eyes.
abstract: OBJECTIVE
  To determine the dependency of straylight on ocular biometry.
  
  
  METHODS
  This prospective study included 518 eyes of 277 volunteers of diverse ethnic backgrounds with healthy eyes of various iris colors. The eyes had retinal straylight tested using a commercial psychophysical device. Ocular axial length and refraction were also measured with an ocular biometer and an autorefractometer, respectively.
  
  
  RESULTS
  The measured retinal straylight was validated by comparing data with the age model described in the literature as log(s) = P(1) + log[1 + (age/65)(4)], where P(1) is the logarithm of the average straylight for the eyes of a newborn. The data agreed well with this model, although P(1) was slightly higher (0.931 vs. 0.87). When this model was subtracted from the measured straylight values, a quadratic increase was found in the function of axial length, L: log(s) = 0.931 + log[1 + (age/65)(4)] + (0.01089L(2) - 0.4820L + 5.330). A similar model was defined for the spherical equivalent refraction SE. This corresponds to an increasing amount of straylight for increasing degrees of myopia. No correlation was found with keratometry and corneal astigmatism or with iris color.
  
  
  CONCLUSIONS
  Retinal straylight increases not only with age, but also with axial length. Further study is needed to identify the cause of this dependency.
authors.affiliation: Department of Ophthalmology, Antwerp University Hospital, Faculty of Medicine, Antwerp University, Belgium. jos.rozema@uza.be
authors.forename: Jos J
authors.initials: JJ
authors.lastname: Rozema
authors.forename: Thomas J T P
authors.initials: TJ
authors.lastname: Van den Berg
authors.forename: Marie-José
authors.initials: MJ
authors.lastname: Tassignon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001699:Biometry; D002648:Child; D005123:Eye / Q000033:anatomy & histology*; D005127:Eye Color; D005260:Female; D006801:Humans; D008027:Light; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012029:Refraction, Ocular / Q000502:physiology; D012160:Retina / Q000528:radiation effects*; D012542:Scattering, Radiation