Clinical ScienceThe Effect of Contact Lens Usage on Corneal Biomechanical Parameters in Myopic PatientsCankaya, Ali B. MD; Beyazyildiz, Emrullah MD; Ileri, Dilek MD; Ozturk, FarukAuthor Information Ulucanlar Eye Research Hospital, Ankara, Turkey. The authors state that they have no financial or conflicts of interest to disclose. Reprints: Ali B. Cankaya, Mutlukent Mah. 1972 Sokak, Melis Sitesi, 3/15, Umitkoy, Cankaya, Ankara, Turkey 06800 (e-mail: email@example.com). Cornea: July 2012 - Volume 31 - Issue 7 - p 764-769 doi: 10.1097/ICO.0b013e3182248239 Buy Metrics Abstract Purpose: To determine and compare the corneal biomechanical properties in myopic patients who use contact lenses and those who do not use contact lenses. Methods: The study consisted of 56 myopic patients who used contact lenses (study group) and 123 myopic patients who did not use contact lenses (control group). Intraocular pressure (IOP) was measured with an ocular response analyzer (ORA) and a Goldmann applanation tonometer. Central corneal thickness was measured with an ultrasonic pachymeter. Axial length and anterior chamber depth measurements were acquired with contact ultrasound A-scan biometry. The differences in ORA parameters between study and control group participants were analyzed. Results: The mean corneal hysteresis in study and control groups was 10.1 ± 1.6 mm Hg (6.5–15.9 mm Hg) and 9.7 ± 1.5 mm Hg (6.3–14.2 mm Hg), respectively (P = 0.16). The mean corneal resistance factor was 10.4 ± 1.9 mm Hg (4.6–15.5 mm Hg) in the study group compared with 9.6 ± 1.9 mm Hg (5.1–15.0 mm Hg) in the control group. The difference for corneal resistance factor was statistically significant (P = 0.014). There was no significant difference in corneal-compensated IOP (P = 0.24). Mean Goldmann-correlated IOP was significantly higher in the study group than in control subjects (15.8 ± 3.2 vs. 14.7 ± 3.7 mm Hg) (P = 0.044). None of the corneal biomechanical parameters was significantly correlated to duration of contact lens usage in the study group. Conclusions: Our results suggest that ORA-generated parameters may be different in subjects with and without contact lens usage. Further longitudinal studies need to be performed to establish the relevance of our results. Copyright © 2012 Wolters Kluwer Health, Inc. All rights reserved.