title: Intraocular pressure and biomechanical corneal properties measure by ocular response analyser in patients with primary congenital glaucoma.
abstract: OBJECTIVE
  To measure the differences in corneal hysteresis (CH) and corneal resistance factor (CRF) in primary congenital glaucoma (PCG) and in control subjects using ocular response analyser (ORA) and also to compare intraocular pressure (IOP) measurements given by ORA against IOP given by Perkins tonometer, a handheld version of Goldman applanation tonometer (GAT), to determine correlation.
  
  
  METHODS
  One hundred and eighteen eyes of 78 patients with PCG (group I) and 103 eyes of 53 controls (group II) were evaluated using ORA. In all participants, IOP was measured using the Perkins tonometer. The ORA device uses applanation pressure peaks to generate the corneal-compensated IOP (IOPcc), which is reportedly independent of corneal thickness, and the measurement of Goldman-correlated IOP (IOPg), which is influenced by corneal thickness.
  
  
  RESULTS
  The measures in group I were as follows: IOPcc 20.92 ± 5.33; IOPg 18.87 ± 6.67; CH 8.51 ± 2.25; CRF 9.85 ± 3.03; and IOP measured by Goldman 18.32 ± 5.13. The measures in group II were as follows: IOPcc 14.33 ± 2.91; IOPg 14.77 ± 3.00; CH 11.37 ± 1.61; CRF 11.02 ± 1.74; and IOP measured by Goldman 13.74 ± 2.42. The differences of all parameters compared between both groups were statistically significant (p < 0.001 for CH and for all IOP measures and p = 0.001 for CRF). The values of IOPcc, IOPg and IOP measured with Goldman were higher in group I than the values in group II. However, CH and CRF values were lower in group I.
  
  
  CONCLUSIONS
  A decrease in CH and CRF has been observed in patients with PCG compared to controls. Future research should assess how these parameters are modified in PCG and whether they could provide more information about progression.
authors.affiliation: Ophthalmology Service, Clínico San Carlos Hospital, Madrid, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: Perucho-González
authors.affiliation: Ophthalmology Service, Clínico San Carlos Hospital, Madrid, Spain.
authors.forename: Jose María
authors.initials: JM
authors.lastname: Martínez de la Casa
authors.affiliation: Ophthalmology Service, Clínico San Carlos Hospital, Madrid, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Morales-Fernández
authors.affiliation: Ophthalmology Service, Clínico San Carlos Hospital, Madrid, Spain.
authors.forename: Paula
authors.initials: P
authors.lastname: Bañeros-Rojas
authors.affiliation: Ophthalmology Service, Clínico San Carlos Hospital, Madrid, Spain.
authors.forename: Federico
authors.initials: F
authors.lastname: Saenz-Francés
authors.affiliation: Ophthalmology Service, Clínico San Carlos Hospital, Madrid, Spain.
authors.forename: Julían
authors.initials: J
authors.lastname: García-Feijoó
mesh_terms: D000293:Adolescent; D000328:Adult; D001696:Biomechanical Phenomena; D002648:Child; D002675:Child, Preschool; D003315:Cornea / Q000502:physiology*; D003430:Cross-Sectional Studies; D004548:Elasticity / Q000502:physiology*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D006871:Hydrophthalmos / Q000503:physiopathology*; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D014065:Tonometry, Ocular / Q000295:instrumentation*; D055815:Young Adult
keywords: corneal biomechanics; corneal hysteresis; corneal resistance factor; ocular response analyser; primary congenital glaucoma