title: Central corneal thickness and biomechanical changes after clear corneal phacoemulsification.
abstract: OBJECTIVE
  To evaluate central corneal thickness (CCT) and ocular biomechanical properties in patients before and after clear corneal phacoemulsification.
  
  
  METHODS
  Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments) in 36 consecutive patients (47 eyes) who underwent clear corneal phacoemulsification. Central corneal thickness was measured with the Pentacam (Oculus Optikgeräte GmbH). All measurements were performed prior to surgery and at follow-up at 1, 7, and 30 days postoperatively.
  
  
  RESULTS
  Central corneal thickness was higher at 1 and 7 days compared to preoperatively (P<.05) but not at 30 days. Corneal hysteresis was lower at 1 day than preoperatively (P<.05) but not at 7 and 30 days. Corneal resistance factor was lower at 1, 7, and 30 days compared to preoperatively (P<.05). Corneal-compensated IOP was slightly lower at 1, 7, and 30 days compared to preoperatively, but was not statistically significant (P>.05). Goldmann-correlated IOP was statistically significantly lower at 1 and 7 days than preoperatively (P<.05).
  
  
  CONCLUSIONS
  Clear corneal phacoemulsification led to a change in ocular biomechanical properties. The increase in CCT after phacoemulsification was followed by a reduction in CRF and CH. Mean IOPcc was similar before and after phacoemulsification, indicating that IOPcc may be a more accurate indicator of true IOP than IOPg.
authors: Fluminense Federal University, Rio de Janeiro, Brazil.
authors: Bruno
authors: B
authors: de Freitas Valbon
authors: Marcelo Palis
authors: MP
authors: Ventura
authors: Renata Siqueira
authors: RS
authors: da Silva
authors: Ana Laura
authors: AL
authors: Canedo
authors: Guillermo Coca
authors: GC
authors: Velarde
authors: Renato
authors: R
authors: Ambrósio
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena / Q000502:physiology; D003315:Cornea / Q000473:pathology* / Q000601:surgery; D004548:Elasticity / Q000502:physiology*; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D019654:Lens Implantation, Intraocular; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification / Q000379:methods*; D011446:Prospective Studies; D019591:Pseudophakia / Q000503:physiopathology