title: Corneal biomechanical properties and intraocular pressure changes after phacoemulsification and intraocular lens implantation.
abstract: OBJECTIVE
  To evaluate corneal viscoelastic and intraocular pressure (IOP) changes measured by an ocular response analyzer (ORA) after phacoemulsification and intraocular lens (IOL) implantation.
  
  
  METHODS
  Yeditepe University Department of Ophthalmology, Istanbul, Turkey.
  
  
  METHODS
  Fifty-one eyes scheduled for cataract surgery were included in the study. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured by ORA preoperatively and 1 week and 1 and 3 months postoperatively. Central corneal thickness (CCT) was measured using the ORA's integrated handheld ultrasonic pachymeter.
  
  
  RESULTS
  The mean preoperative CCT (537 microm+/-46 [SD]) did not change significantly by the end of 1 month postoperatively. The mean preoperative IOPcc (17.2+/-3.0 mm Hg) decreased significantly by 3 months postoperatively (15.2+/-3.7 mm Hg) (P= .018). The mean CH decreased from 10.36+/-1.48 mm Hg preoperatively to 9.64+/-1.26 mm Hg at 1 week (P= .028); it increased to preoperative values at the end of 1 month (10.20+/-1.70) and 3 months (10.74+/-1.54) (P>.05). The mean CRF decreased from 10.94+/-2.54 mm Hg preoperatively to 9.99+/-1.77 at 1 week (P= .026); it increased to preoperative values at 1 month (10.26+/-1.59) and 3 months (10.35+/-1.46) (P>.05).
  
  
  CONCLUSIONS
  Although CH and the CRF decreased in the early postoperative period, the parameters increased and reached preoperative values by 3 months postoperatively, showing that corneal biomechanical properties are influenced by phacoemulsification and IOL implantation.
authors.affiliation: Department of Ophthalmology, Yeditepe University Eye Hospital, Istanbul, Turkey. berilkucumen@hotmail.com
authors.forename: Raciha Beril
authors.initials: RB
authors.lastname: Kucumen
authors.forename: Nursal Melda
authors.initials: NM
authors.lastname: Yenerel
authors.forename: Ebru
authors.initials: E
authors.lastname: Gorgun
authors.forename: Destan Nil
authors.initials: DN
authors.lastname: Kulacoglu
authors.forename: Banu
authors.initials: B
authors.lastname: Oncel
authors.forename: Maryo Cenk
authors.initials: MC
authors.lastname: Kohen
authors.forename: Murat Levent
authors.initials: ML
authors.lastname: Alimgil
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology; D003315:Cornea / Q000502:physiology*; D004548:Elasticity / Q000502:physiology*; D005500:Follow-Up Studies; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D019654:Lens Implantation, Intraocular; D018918:Phacoemulsification; D011184:Postoperative Period; D011446:Prospective Studies; D014065:Tonometry, Ocular