title: A comparison of corneal biomechanical properties in patients with psoriasis and healthy subjects.
abstract: OBJECTIVE
  To evaluate the differences in corneal biomechanical properties between healthy subjects and patients with psoriasis using the ocular response analyzer (ORA).
  
  
  METHODS
  Fifty-nine eyes of 59 psoriasis patients and 66 healthy individuals were included in the study. Corneal biomechanical parameters were obtained using ORA. Ultrasound pachymetry was used to measure central corneal thickness (CCT). The main parameters assessed were corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg) measurement and corneal-compensated IOP (IOPcc) through ORA. The dry eye evaluation was performed with tear break-up time (TBUT) and Shirmer test.
  
  
  RESULTS
  The mean CH values in psoriasis and healthy subject eyes were 10.75±2.9 mm Hg, 11.97±3.6 mm Hg, respectively (P=0.047). The mean CRF values were 10.14±3.1 mm Hg and 11.61±3.3 mm Hg, respectively (P=0.012). The mean CCT were 539.1±36 μm and 536.3±28 μm, respectively (P=0.643). Mean TBUT values were 8.2±2.9 sec in psoriasis group and 10.4±3.6 sec in healthy subjects (P<0.001). Shirmer test values were less (8.9±3.8 mm/5 min) in psoriasis than in healthy subjects (13.1±3.6 mm) (P<0.001).
  
  
  CONCLUSIONS
  Psoriasis can influence the corneal biomechanical properties. Patients with psoriasis had lower CH and CRF, but higher IOPg and IOPcc values than healthy controls. These corneal biomechanical changes should be considered when determining IOP values.
authors.affiliation: Department of Ophthalmology (U.C., V.A.), Gaziosmanpaşa Taksim Training and Research Hospital, Istanbul, Turkey; Department of Ophthalmology (B.C.), Beyoglu Eye Training and Research Hospital, Istanbul, Turkey; Department of Ophthalmology (M.T.), Malatya State Hospital, Malatya, Turkey; Department of Ophthalmology (S.Y.), Zonguldak Karaelmas University, Zonguldak, Turkey; Department of Ophthalmology (H.K.), Bağcılar Training and Research Hospital, Istanbul, Turkey; and Department of Ophthalmology (S.K.E.), Medipol University, Istanbul, Turkey.
authors.forename: Ugur
authors.initials: U
authors.lastname: Celik
authors.forename: Veysel
authors.initials: V
authors.lastname: Aykut
authors.forename: Burcu
authors.initials: B
authors.lastname: Celik
authors.forename: Mehmet
authors.initials: M
authors.lastname: Tas
authors.forename: Serpil
authors.initials: S
authors.lastname: Yazgan
authors.forename: Havva
authors.initials: H
authors.lastname: Kaldrm
authors.forename: Sevil Karaman
authors.initials: SK
authors.lastname: Erdur
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D003315:Cornea / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D063171:Corneal Pachymetry; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000378:metabolism / Q000503:physiopathology*; D013666:Tears / Q000378:metabolism; D014065:Tonometry, Ocular; D014463:Ultrasonography