title: Reliability of automatic biometric iris recognition after phacoemulsification or drug-induced pupil dilation.
abstract: OBJECTIVE
  To investigate the reliability of a biometric iris recognition system for personal authentication after cataract surgery or iatrogenic pupil dilation.
  
  
  METHODS
  This was a prospective, nonrandomized, single-center, cohort study for evaluating the performance of an iris recognition system 2-24 hours after phacoemulsification and intraocular lens implantation (group 1) and before and after iatrogenic pupil dilation (group 2).
  
  
  RESULTS
  Of the 173 eyes that could be enrolled before cataract surgery, 164 (94.8%) were easily recognized postoperatively, whereas in 9 (5.2%) this was not possible. However, these 9 eyes could be reenrolled and afterwards recognized successfully. In group 2, of a total of 184 eyes that were enrolled in miosis, a total of 22 (11.9%) could not be recognized in mydriasis and therefore needed reenrollment. No single case of false-positive acceptance occurred in either group.
  
  
  CONCLUSIONS
  The results of this trial indicate that standard cataract surgery seems not to be a limiting factor for iris recognition in the large majority of cases. Some patients (5.2% in this study) might need "reenrollment" after cataract surgery. Iris recognition was primarily successful in eyes with medically dilated pupils in nearly 9 out of 10 eyes. No single case of false-positive acceptance occurred in either group in this trial. It seems therefore that iris recognition is a valid biometric method in the majority of cases after cataract surgery or after pupil dilation.
authors.affiliation: Department of Ophthalmology, Paracelsus Medical University, Salzburg - Austria.
authors.forename: Orang
authors.initials: O
authors.lastname: Seyeddain
authors.forename: Hannes
authors.initials: H
authors.lastname: Kraker
authors.forename: Andreas
authors.initials: A
authors.lastname: Redlberger
authors.forename: Alois K
authors.initials: AK
authors.lastname: Dexl
authors.forename: Günther
authors.initials: G
authors.lastname: Grabner
authors.forename: Martin
authors.initials: M
authors.lastname: Emesz
mesh_terms: D056667:Biometric Identification / Q000379:methods*; D005260:Female; D006801:Humans; D007498:Iris / Q000033:anatomy & histology*; D019654:Lens Implantation, Intraocular; D008297:Male; D009184:Mydriatics / Q000008:administration & dosage*; D010363:Pattern Recognition, Automated; D018918:Phacoemulsification; D011184:Postoperative Period; D011446:Prospective Studies; D011680:Pupil / Q000187:drug effects*; D015203:Reproducibility of Results; D014331:Tropicamide / Q000008:administration & dosage
chemical_list: D009184:Mydriatics; D014331:Tropicamide