title: Corneal Biomechanical Changes Following Toric Soft Contact Lens Wear.
abstract: OBJECTIVE
  To determine the effect of using toric soft contact lenses on corneal biomechanical properties.
  
  
  METHODS
  We enrolled 33 healthy patients with mean age of 23.18 ± 4.06 and minimal cylinder power of 1 D (-1.98 ± 0.808 SD) and negative history of contact lens use; keratoconic patients were excluded from the study. Toric soft contact lenses (BIOFINITY, Comfilcon A, Coopervision, Southampton, UK) were fitted in all participants. The Ocular Response Analyzer (Reichert Ophthalmic Instruments, Depew, New York, USA) was used to measure corneal hysteresis (CH), corneal resistance factor (CRF), and the Pentacam HR (Oculus, Inc., Lynnwood, WA, USA) was used to measure central corneal thickness (CCT) and mean keratometry (K mean) before and one week, one month, and three months after using the toric soft contact lenses.
  
  
  RESULTS
  CH and CRF were decreased significantly one month after using the contact lens; mean CH decreased from 9.99 ± 1.44 to 9.59 ± 1.54 mmHg, and mean CRF decreased from 9.96 ± 1.71 to 9.63 ± 1.73 mmHg (P = 0.013 and P = 0.017, respectively). Mean CCT and K mean did not show a significant change during the period of toric soft contact lens use.
  
  
  CONCLUSIONS
  CH and CRF decreased significantly one month after fitting toric soft contact lenses while CCT and Kmean did not change significantly. Corneal biomechanical parameters may alter with toric soft contact lens use and such changes may have implications with long-term use such lenses.
authors.affiliation: Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran.
authors.forename: Somayeh
authors.initials: S
authors.lastname: Radaie-Moghadam
authors.affiliation: Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Hashemi
authors.affiliation: Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran.
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Jafarzadehpur
authors.affiliation: Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Abbas Ali
authors.initials: AA
authors.lastname: Yekta
authors.affiliation: Department of Medical Surgical Nursing, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Khabazkhoob
keywords: Corneal Hysteresis; Corneal Resistance Factor; Toric Soft Contact Lens