title: [Accommodation ability under the aspect of refractive, demographic, and biometric parameters].
abstract: OBJECTIVE
  The aim of this study was to evaluate the accommodation ability in healthy phakic eyes in relation to refraction and biometric parameters in order to get comparable results for patients with the accommodative 1 CU posterior chamber lens.
  
  
  METHODS
  The study included 120 normal eyes of 120 patients (77 males, 43 females, mean age: 40+/-18, range: 11-70 years). The inclusion criteria were spherical equivalent for distance refraction <2 D, astigmatism <1.5 D, and a best-corrected visual acuity > or =0.8. Exclusion criteria were diabetes, glaucoma, cataract, traumas, or previous surgery. Subjects were divided into six age groups at increments of 10 years. Each group consisted of 20 subjects. Measurements included subjective and objective refraction (D), the accommodation ability (D) assessed with an accommodometer, and biometric parameters using the IOLMaster. In addition, the relation of anterior chamber depth and length of the eye was calculated for analyzing the relationship of anterior eye segment and accommodation.
  
  
  RESULTS
  The spherical equivalent for distance refraction was 0.04+/-0.6 D with a range of -1.5 to 2.0 D. There was no sex-related significant difference of accommodation range. The accommodation range (D) decreased significantly with increasing age (p<0.0001, r=-0.895). The highest decrease could be found between the ages of 30 and 50 years. In subsequent years, the decline in accommodation ability was comparatively less. In association with the anterior chamber depth and the relation of anterior chamber depth and length of the eye, the accommodation ability fell with increasing age (p<0.001). The length of the eye did not correlate with the accommodation ability (p=0.8).
  
  
  CONCLUSIONS
  There is a strong relationship between accommodation ability and age. Accommodation ability decreases strongly from the 3rd to the 5th decade; after that the loss of accommodation ability is relatively lower. The increase in lens thickness during the life span can implicate a correlation between the change of anterior chamber depth in relation to the length of the eye and a decrease of accommodation ability. Our results confirm Duane's hypothesis of accommodation and age.
authors.affiliation: Universitätsaugenklinik mit Poliklinik, Universität Bonn, Ernst-Abbe-Strasse 2, 53127 Bonn. Kristine.Klatt@ukb.uni-bonn.de
authors.forename: K
authors.initials: K
authors.lastname: Klatt
authors.forename: A
authors.initials: A
authors.lastname: Langenbucher
authors.forename: B
authors.initials: B
authors.lastname: Seitz
authors.forename: N X
authors.initials: NX
authors.lastname: Nguyen
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000867:Anterior Chamber / Q000502:physiology*; D001699:Biometry; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009887:Ophthalmoscopy; D012016:Reference Values; D012029:Refraction, Ocular; D012737:Sex Factors