title: Changes in Ocular Parameters and Intraocular Lens Powers in Aging Cycloplegic Eyes.
abstract: OBJECTIVE
  Age-related changes in lens elasticity and ciliary muscle contractility can affect how ocular parameters respond to cycloplegia, and therefore intraocular lens (IOL) power measurements calculated by formulas using anterior chamber depth (ACD), lens thickness (LT), or white-to-white (WtW) for effective lens position prediction can vary. In response, using swept-source optical biometry in prepresbyopic and presbyopic eyes, we investigated changes in ocular parameters and IOL power calculations attributable to cycloplegia.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  In 38 prepresbyopic and 42 presbyopic eyes, we measured pupil diameter, radius of corneal curvature values, central corneal thickness, WtW, ACD, LT, and axial length both before and after cycloplegia. We determined IOL power calculations with the Sanders-Retzlaff-Kraff/theoretical, Holladay 2, and Haigis formulas. To pinpoint the effect of cycloplegia, we recorded refractive predictions in pre- and postdilation conditions according to the same IOL power calculations, even if postdilation IOL power calculations had changed.
  
  
  RESULTS
  With cycloplegia, pupil diameter changed significantly more in presbyopic eyes (P < .001). Central corneal thickness decreased in prepresbyopic eyes (P = .048), whereas WtW increased in presbyopic eyes (P = .02). In both groups, ACD and LT changed significantly (P < .001). IOL power calculations according to the Holladay 2 formula differed in prepresbyopic eyes (P = .042), and refractive predictions with the Holladay 2 and Haigis formulas differed significantly in prepresbyopic eyes (P = .043 and P = .022, respectively).
  
  
  CONCLUSIONS
  Surgeons should consider the effect of cycloplegia on refractive prediction errors and IOL power calculations determined with Haigis and Holladay 2 formulas, especially in prepresbyopic ages.
authors.affiliation: Ophthalmology Department, Mugla Sitki Kocman University Faculty of Medicine, Mugla, Turkey. Electronic address: pelingesoglu@yahoo.com.tr.
authors.forename: Pelin
authors.initials: P
authors.lastname: Özyol
authors.affiliation: Ophthalmology Department, Mugla Sitki Kocman University Training and Research Hospital, Mugla, Turkey.
authors.forename: Erhan
authors.initials: E
authors.lastname: Özyol
authors.affiliation: Department of Biostatistics, Faculty of Medicine, Mugla University, Mugla, Turkey.
authors.forename: Ercan
authors.initials: E
authors.lastname: Baldemir
mesh_terms: D000328:Adult; D000375:Aging; D058452:Axial Length, Eye / Q000033:anatomy & histology* / Q000187:drug effects; D001699:Biometry / Q000379:methods*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D009184:Mydriatics / Q000494:pharmacology*; D055095:Optics and Photonics; D011305:Presbyopia / Q000175:diagnosis* / Q000503:physiopathology; D012372:ROC Curve; D012029:Refraction, Ocular / Q000502:physiology*; D055815:Young Adult
chemical_list: D009184:Mydriatics