Abstract
Purpose: :
Determine whether prostaglandin analogs induce errors in intraocular pressure (IOP) measurement by altering corneal biomechanical properties, principally hysteresis.
Methods: :
We selected 28 patients diagnosed with glaucoma who had never previously received antiglaucomatous treatment; they were divided into groups of patients receiving latanoprost (10 patients), travoprost (9 patients), or timolol maleate (9-patient control group).The patients were assessed prior to treatment administration and they were later reassessed at two months by Goldmann applanation tonometry (GAT), ultrasound pachymetry and Ocular Response Analyzer (ORA), thus determining pachymetry and corneal hysteresis.
Results: :
GAT IOP and ORA IOPcc decreased significantly after treatment with prostaglandins (p< 0.001). There weren't changes in central corneal thickness and corneal curvature (p<0.5) after treatment (p<0.42). However, corneal hysteresis increased significantly (p<0.001) in both groups treated with prostaglandins whereas it wasn't modified in a significant way in control group (p<0.09).
Conclusions: :
Prostaglandins might induce changes by increasing corneal hysteresis, the final pressure thus being overestimated and the pressure drop greater than expected, thereby highlighting their extensive hypotensive efficacy.
Keywords: intraocular pressure • cornea: stroma and keratocytes