title: Rotational and centration stability of an aspheric intraocular lens with a simulated toric design.
abstract: OBJECTIVE
  To assess the stability of the Akreos AO intraocular lens (IOL) platform with a simulated toric design using objective image analysis.
  
  
  METHODS
  Six hospital eye clinics across Europe.
  
  
  METHODS
  After implantation in 1 eye of patients, IOLs with orientation marks were imaged at 1 to 2 days, 7 to 14 days, 30 to 60 days, and 120 to 180 days. The axis of rotation and IOL centration were objectively assessed using validated image analysis.
  
  
  RESULTS
  The study enrolled 107 patients with a mean age of 69.9 years +/- 7.7 (SD). The image quality was sufficient for IOL rotation analysis in 91% of eyes. The mean rotation between the first day postoperatively and 120 to 180 days was 1.93 +/- 2.33 degrees, with 96% of IOLs rotating fewer than 5 degrees and 99% rotating fewer than 10 degrees. There was no significant rotation between visits and no clear bias in the direction of rotation. In 71% of eyes, the dilation and image quality was sufficient for image analysis of centration. The mean change in centration between 1 day and 120 to 180 days was 0.21 +/- 0.11 mm, with all IOLs decentering less than 0.5 mm. There was no significant decentration between visits and no clear bias in the direction of the decentration.
  
  
  CONCLUSIONS
  Objective analysis of digital retroillumination images taken at different postoperative periods shows the aspheric IOL platform was stable in the eye and is therefore suitable for the application of a toric surface to correct corneal astigmatism.
authors.affiliation: Aston University, School of Life and Health Sciences, Ophthalmic Research Group, Birmingham, United Kingdom.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Buckhurst
authors.forename: James S
authors.initials: JS
authors.lastname: Wolffsohn
authors.forename: Shehzad A
authors.initials: SA
authors.lastname: Naroo
authors.forename: Leon N
authors.initials: LN
authors.lastname: Davies
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000517:prevention & control; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012029:Refraction, Ocular / Q000502:physiology; D012399:Rotation