title: Evaluation of optical function using a new point spread function analysis system in cataractous and pseudophakic eyes: preliminary results.
abstract: OBJECTIVE
  To evaluate optical function in cataractous and pseudophakic eyes using the new point spread function (PSF) analysis system in a clinical setting.
  
  
  METHODS
  We applied this new analysis system in the study of two cataractous eyes and one pseudophakic eye of two patients. Using a PSF analyzer, double-pass PSF was measured directly for each subject, and the single-pass modulation transfer function (MTF) and single-pass PSF were calculated. The simulated retinal images of various sizes of Landolt's rings and their contrast characteristics were also calculated by the PSF analyzer.
  
  
  RESULTS
  The MTF and the contrast of the simulated retinal images degraded in cataractous eyes were compared with data for normal eyes; the degradation pattern depended on the opacification pattern. The MTF and the contrast of the simulated retinal images in the pseudophakic eye improved significantly compared with the cataractous eyes, although both values were lower in the pseudophakic eye than in young normal eyes.
  
  
  CONCLUSIONS
  Our data showed degradation of optical function in cataractous and pseudophakic eyes in comparison with optical function in young normal eyes. If further accumulations of PSF data are made, it may be possible to establish an objective standard by which to measure the progression of cataract, as well as an objective indication for treatment in the future.
authors.affiliation: Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan. fwic7788@infoweb.ne.jp
authors.forename: Kazuno
authors.initials: K
authors.lastname: Negishi
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ohnuma
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohno
authors.forename: Toru
authors.initials: T
authors.lastname: Noda
mesh_terms: D000368:Aged; D002386:Cataract / Q000503:physiopathology*; D015350:Contrast Sensitivity / Q000502:physiology*; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D018918:Phacoemulsification; D019591:Pseudophakia / Q000503:physiopathology*; D012160:Retina / Q000503:physiopathology*; D014792:Visual Acuity / Q000502:physiology