title: Distribution of the Crystalline Lens Power In Vivo as a Function of Age.
abstract: OBJECTIVE
  To observe the age-related changes in crystalline lens power in vivo in a noncataractous European population.
  
  
  METHODS
  Data were obtained though Project Gullstrand, a multicenter population study with data from healthy phakic subjects between 20 and 85 years old. One randomly selected eye per subject was used. Lens power was calculated using the modified Bennett-Rabbetts method, using biometry data from an autorefractometer, Oculus Pentacam, and Haag-Streit Lenstar.
  
  
  RESULTS
  The study included 1069 Caucasian subjects (490 men, 579 women) with a mean age of 44.2 ± 14.2 years and mean lens power of 24.96 ± 2.18 diopters (D). The average lens power showed a statistically significant decrease as a function of age, with a steeper rate of decrease after the age of 55. The highest crystalline lens power was found in emmetropic eyes and eyes with a short axial length. The correlation of lens power with different refractive components was statistically significant for axial length (r = -0.523, P < 0.01) and anterior chamber depth (r = -0.161, P < 0.01), but not for spherical equivalent and corneal power (P > 0.05).
  
  
  CONCLUSIONS
  This in vivo study showed a monotonous decrease in crystalline lens power with age, with a steeper decline after 55 years. While this finding fundamentally concurs with previous in vivo studies, it is at odds with studies performed on donor eyes that reported lens power increases after the age of 55.
authors.affiliation: Department of Ophthalmology University Hospital Antwerp, Edegem, Belgium.
authors.forename: Sien
authors.initials: S
authors.lastname: Jongenelen
authors.affiliation: Department of Ophthalmology University Hospital Antwerp, Edegem, Belgium 2Faculty of Medicine and Health Sciences, University of Antwerp, Wilrijk, Belgium.
authors.forename: Jos J
authors.initials: JJ
authors.lastname: Rozema
authors.affiliation: Department of Ophthalmology University Hospital Antwerp, Edegem, Belgium.
authors.forename: Marie-José
authors.initials: MJ
authors.lastname: Tassignon
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001699:Biometry; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007908:Lens, Crystalline / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012029:Refraction, Ocular; D012030:Refractive Errors / Q000175:diagnosis / Q000503:physiopathology*; D055815:Young Adult