Abstract
Purpose:
To measure intraocular pressure changes with applanation tonometry (AT), dynamic contour tonometry (DCT) and ocular response analyzer (ORA) in eyes with glaucoma treated with prostaglandin analogues (PGA)
Methods:
Intraocular pressure (IOP) was measured using AT, DCT and ORA in 38 glaucoma eyes at baseline and after 3 weeks of treatment with PGA. Baseline mean difference in IOP between tonometers was compared to differences with treatment. Paired samples T test was used for pre and post-treatment comparisons.Central Corneal Thickness (CCT),corneal hysteresis (CH) and corneal resistance factor (CRF) were also measured and analysed using SPSS version 19
Results:
Eyes treated with PGAs have lower IOP than at baseline, but each tonometry method shows a different mean amount of IOP lowering. Baseline and treated mean IOPs were different among the 3 tonometers, mean change in IOP as measured by AT was -1.21 mmHg, -1.26 mmHg with DCT and 3 mmHg with ORA . Corneal hysteresis increases an average of 0.83 mmHg while corneal thickness decreases an average of 7.8 microns, corneal resistance factor does not experience a significant change with prostaglandin analogue treatment
Conclusions:
AT and DCT seem to be less affected by corneal biomechanical changes induced by PGAs, whereas ORA measurements show an artifactual larger effect of PGAs on IOP; corneal hysteresis increases significantly post treatment with this kind of drugs.Corneal thickness decreases with prostaglandin analogue treatment
Keywords: 465 clinical (human) or epidemiologic studies: systems/equipment/techniques