Intraocular Pressure Measurements Using Dynamic Contour Tonometer After Photorefractive Keratectomy

ABSTRACT

PURPOSE: To assess the performance of the dynamic contour tonometer (DCT) in eyes undergoing excimer laser photorefractive keratectomy (PRK). METHODS: Intraocular pressure (IOP) was measured in 30 eyes after first time excimer laser PRK pre and three months post operatively using Goldmann applanation tonometer (GAT), noncontact air tonometer (NCT), and the DCT. RESULTS: There was significant correlation between central corneal thickness (CCT) and IOP measurements by GAT and NCT (CCT vs GAT r2=0.31, p<0.01, CCT vs NCT r2=0.39, p<0.01). However, the correlation between CCT and IOP measurements by DCT was not significant (CCT vs DCT r2=0.14, p=0.32). After PRK, the mean change in CCT and IOP measurements using GAT, NCT, DCT were 73.70+/-26.92 micrometer (mean+/-SD), 2.43+/-2.86 mmHg (p<0.01), 3.83+/-2.34 mmHg (p<0.01) and 0.44+/-1.51 mmHg (p=0.125), respectively. The preoperative and postoperative DCT measurements did not differ significantly. CONCLUSIONS: The reduction in CCT induced by PRK doesn't appear to influence DCT measurements; therefore, DCT may be better suited over GAT or NCT for monitoring IOP in eyes that underwent refractive surgery.