title: Effect of the pigment-free optical zone diameter of decorative tinted soft contact lenses on visual function.
abstract: OBJECTIVE
  We investigated changes in visual function after wearing decorative tinted soft contact lenses with different pigment-free optical zone diameters.
  
  
  METHODS
  A prospective study was performed in 30 eyes of 30 healthy volunteers. Best-corrected visual acuity (BCVA), ocular higher-order aberrations (HOAs), modulation transfer function (MTF), Strehl ratio and contrast sensitivity were evaluated after wearing clear lens and tinted lenses with different pigment-free optical zone diameters (4, 5 and 6 mm).
  
  
  RESULTS
  BCVA decreased from 0.00 logMAR after wearing a clear lens to 0.04±0.04 logMAR after wearing 4 mm optical zone lens (p<0.001). As the optical zone diameter decreased, ocular aberrations were induced. Total HOAs, coma aberration and secondary astigmatism showed significant difference between clear lens and 5 or 4 mm optical zone lenses (p<0.050). Spherical aberration and trefoil showed significant difference between clear lens and 4 mm optical zone lens (p<0.050). The results for Strehl ratio revealed poorer optical quality for both 5 and 4 mm optical zone lens (both p=0.002). The entire ocular MTF was significantly different, corresponding to the decreased optical zone diameter. The HOAs showed a correlation with the blocked pupil covered by the tinted part (r=0.435, p<0.001). In photopic and mesopic conditions, the contrast sensitivity decreased significantly with the reduced pigment-free optical zone diameters.
  
  
  CONCLUSIONS
  Decorative tinted contact lenses significantly increased ocular aberrations and decreased optical quality and contrast sensitivity, as the pigment-free optical zone diameter decreased. Therefore, consumers of tinted lenses should be informed about the possible disturbance in visual function.
  
  
  BACKGROUND
  NCT02537275.
authors.affiliation: Department of Ophthalmology, The Institute of Vision Research, Yonsei University College of Medicine, Seoul, South Korea Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, South Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Jung
authors.affiliation: Department of Ophthalmology, The Institute of Vision Research, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Sang Myung
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology, The Institute of Vision Research, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Sun Hyup
authors.initials: SH
authors.lastname: Han
authors.affiliation: Department of Ophthalmology, The Institute of Vision Research, Yonsei University College of Medicine, Seoul, South Korea Corneal Dystrophy Research Institute, Severance Biomedical Science Institute, and Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Eung Kweon
authors.initials: EK
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology, The Institute of Vision Research, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Kyoung Yul
authors.initials: KY
authors.lastname: Seo
authors.affiliation: Department of Ophthalmology, The Institute of Vision Research, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Tae-Im
authors.initials: TI
authors.lastname: Kim
mesh_terms: D000328:Adult; D001251:Astigmatism / Q000503:physiopathology; D003263:Contact Lenses, Hydrophilic; D015350:Contrast Sensitivity / Q000502:physiology*; D057108:Corneal Wavefront Aberration / Q000503:physiopathology; D003357:Cosmetic Techniques / Q000295:instrumentation*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011680:Pupil / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology*; D055815:Young Adult
keywords: Contact lens