title: Evaluating the Biostability of Yellow and Clear Intraocular Lenses with a System Simulating Natural Intraocular Environment.
abstract: OBJECTIVE
  Blue light-filtering intraocular lenses (IOLs) are thought to protect the retina from blue light damage after cataract surgery, and the implantation of yellow-tinted IOLs has been commonly used in cataract surgery. To our knowledge, this is the first investigation measuring the long-term biostability of yellow-tinted IOLs using an in vitro system simulating natural intraocular environment.
  
  
  METHODS
  Six hydrophobic acrylic IOLs, three clear IOLs, and three yellow-tinted IOLs were included in the study. Each yellow-tinted IOL was a matching counterpart of a clear IOL, with the only difference being the lens color. The IOLs were kept in conditions replicating the intraocular environment using a perfusion culture system for 7 months. Resolution, light transmittance rate, and the modulation transfer function (MTF) were measured before and after culturing. Surface roughness of the anterior and posterior surfaces was also measured.
  
  
  RESULTS
  After culturing for 7 months, there were no changes in the resolution, the light transmittance rate, and MTF. The surface roughness of the anterior and posterior surfaces increased after culturing; however, this increase was clinically insignificant. There were no differences in surface roughness between the clear and yellow-tinted IOLs, either before or after culturing.
  
  
  CONCLUSIONS
  A novel in vitro system replicating intraocular environment was used to investigate the biostability of yellow-tinted IOLs. The surface roughness showed no clinically significant increase after culturing for 7 months.
  
  
  CONCLUSIONS
  This system is useful for evaluating the biostability of IOLs.
authors.affiliation: Department of Ophthalmology, Koshigaya Hospital, Dokkyo Medical University, Koshigaya, Saitama, Japan.
authors.forename: Rijo
authors.initials: R
authors.lastname: Hayashi
authors.affiliation: Department of Ophthalmology, Koshigaya Hospital, Dokkyo Medical University, Koshigaya, Saitama, Japan ; Lively Eye Clinic, Soka, Saitama, Japan.
authors.forename: Shimmin
authors.initials: S
authors.lastname: Hayashi
authors.affiliation: Department of Ophthalmology, Koshigaya Hospital, Dokkyo Medical University, Koshigaya, Saitama, Japan.
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Arai
authors.affiliation: Department of Ophthalmology, Koshigaya Hospital, Dokkyo Medical University, Koshigaya, Saitama, Japan ; Yoshida Eye Hospital, Hokodate, Hokkaido, Japan.
authors.forename: Shinichirou
authors.initials: S
authors.lastname: Yoshida
authors.affiliation: Department of Ophthalmology, Koshigaya Hospital, Dokkyo Medical University, Koshigaya, Saitama, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Chikuda
authors.affiliation: Department of Ophthalmology, Koshigaya Hospital, Dokkyo Medical University, Koshigaya, Saitama, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Machida
keywords: in vitro culturing; intraocular lens; longterm biostability