title: Intraocular Pressure Measurements Referring to the Corneal Thickness in Keratoconic Eyes After Corneal Crosslinking with Riboflavin and Ultraviolet A.
abstract: OBJECTIVE
  To determine the possible relation between intraocular pressure (IOP), central corneal thickness (CCT) and corneal resistance (CR) in kerotoconic eyes before, 3,6 and 12 months after collagen crosslinking procedure (CXL) with aim to find out does the thicker cornea means already more resistance cornea followed with higher IOP.
  
  
  METHODS
  Thirty eyes (30 patients) with central keratoconus (KC)were evaluated in retrospective cross sectional study. The corneal biomechanical parameters were taken with Wave Light Allegro Oculyzer produced by Alcon before the CXL, 3, 6 and 12 months after the procedure. IOP were checked by Goldmann applanation tonometry (GAT) before, 3, 6 and 12 months after CXL.
  
  
  RESULTS
  The value of IOP before the CXL was 12,0 mmHg (10,62-15,25 mmHg), 3 months later 13,5 mmHg (11,0-16,0 mmHg), 6 months 14,0 mmHg (11,0-16,0 mmHg) and 12 months later 15,0 mmHg (10,37-17,25 mmHg) and was statistically significant higher (p=0,015) comparing to the value of IOP 3 months after the CXL, IOP 12 months after CXL procedure was statistically significant higher comparing to preoperative values (p=0,010). There were no statistically significant difference between the values 3 and 6 months after CXL. The CCT before the CXL procedure was 449 (433-505,75 microns), 3 months after CXL was 420 (383-473microns, p < 0,005), 6 months later 437 (401,25-480,25, p=0,001), 12 months after CXL 437 (401-503 microns, p=0,001). However there is statistically significant difference in CCT 12 months after CXL 437 (401-503microns p=0,032) and the value of CCT 3 months later the procedure (p=0,004) and the CCT 12 months after CXL and the value of CXL 6 months after CXL (p=0,036). The value of CCT did not show any statistically significant difference 3 and 6 months postoperatively.
  
  
  CONCLUSIONS
  After riboflavin-UVA CXL in eyes with KC there was significant decrease in central corneal thickness 3 and 6 months after the procedure and the thickness is almost the same 12 months later. However IOP is low before CXL, raising up 3 and 6 months after CXL but significant increase is seen 12 months later. It means the regular measurement of IOP could be the serious and confident indicator of increasing of corneal resistance which is the main goal of CXL treatment.
authors.affiliation: Eye Polyclinic "Dr. Sefic", Sarajevo, Bosnia and Herzegovina.
authors.forename: Sanja Sefic
authors.initials: SS
authors.lastname: Kasumovic
authors.affiliation: University Clinical Center, Banjaluka, Bosnia and Herzegovina.
authors.forename: Milka
authors.initials: M
authors.lastname: Mavija
authors.affiliation: Eye Polyclinic "Dr. Sefic", Sarajevo, Bosnia and Herzegovina.
authors.forename: Aida
authors.initials: A
authors.lastname: Kasumovic
authors.affiliation: Department of Human Physiology, Faculty of Medicine, University of Sarajevo, Bosnia and Herzegovina.
authors.forename: Orhan
authors.initials: O
authors.lastname: Lepara
authors.affiliation: Cantonal hospital 2Dr. Irfan Ljubijankic", Bihac, Bosnia and Herzegovina.
authors.forename: Belkisa
authors.initials: B
authors.lastname: Duric-Colic
authors.affiliation: Public Health Care Institution Doboj-Jug, Matuzici, Bosnia and Herzegovina.
authors.forename: Emir
authors.initials: E
authors.lastname: Cabric
authors.affiliation: The Public Institution Health Centre of Sarajevo Canton, Bosnia and Herzegovina.
authors.forename: Lejla
authors.initials: L
authors.lastname: Muhamedagic
authors.affiliation: Eye Clinic, Clinical Center University of Sarajevo, Bosnia and Herzegovina.
authors.forename: Adisa
authors.initials: A
authors.lastname: Sakovic-Racic
authors.affiliation: Laser Fokus Centre for Eye Microsurgery, Belgrade, Serbia.
authors.forename: Mirko
authors.initials: M
authors.lastname: Jankov
mesh_terms: D000328:Adult; D003315:Cornea / Q000473:pathology*; D003432:Cross-Linking Reagents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D007640:Keratoconus / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D012189:Retrospective Studies; D012256:Riboflavin / Q000627:therapeutic use*; D014065:Tonometry, Ocular; D014467:Ultraviolet Therapy / Q000379:methods*; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D012256:Riboflavin
keywords: central corneal thickness; collagen crosslinking; corneal resistance; intraocular pressure; keratoconus