title: Optical considerations in the contact lens correction of infant aphakia.
abstract: BACKGROUND
  Correction of infant aphakia with conventional soft and rigid designs induces significant amounts of positive spherical aberration.
  
  
  METHODS
  Different levels of positive spherical aberration were induced by rigid lenses positioned close to the eye. Visual acuity and depth of focus were measured for twelve young adult subjects.
  
  
  RESULTS
  Positive spherical aberration acts to produce an increase in relative depth of focus, but because of the reduction of best visual acuity, there is a concurrent decrease in absolute depth of focus. As the spherical aberration increases, there is a progressive loss of best-corrected visual acuity.
  
  
  CONCLUSIONS
  The correction of spherical aberration in contact lenses for infant aphakia provides the best theoretical optical conditions for normal ocular growth and visual development. We provide examples of the optimal aspheric surfaces to minimize spherical aberration in contact lenses for infant aphakes.
authors: Contact Lens and Visual Optics Laboratory, Centre for Eye Research, Queensland University of Technology, Brisbane, Australia. m.collins@qut.edu.au
authors: Michael J
authors: MJ
authors: Collins
authors: Ross
authors: R
authors: Franklin
authors: Brett A
authors: BA
authors: Davis
mesh_terms: D000328:Adult; D001036:Aphakia, Postcataract / Q000503:physiopathology / Q000534:rehabilitation*; D003261:Contact Lenses; D003290:Convergence, Ocular; D006801:Humans; D007223:Infant; D008962:Models, Theoretical; D055095:Optics and Photonics; D014792:Visual Acuity