Effects of topical dorzolamide on IOP after phacoemulsification with different types of ophthalmic viscosurgical devices

PURPOSE. TO evaluate the effect of topical dorzolamide on postoperative intraocular pressure (IOP) after routine phacoemulsification surgery with different type of ophthalmic viscosurgical device (OVD). METHODS. Patients who were scheduled for phacoemulsification with intraocular lens (IOL) implantation were evenly divided into four groups. Group I (83 eyes) received one drop of topical dorzolamide immediately after surgery and 1.4% NaHa (BD Visc (R)) was used as a cohesive OVD during IOL implantation. Group II (83 eyes) did not receive any topical antiglaucoma medication after operation and 1.4% NaHa was used as a cohesive OVD. Group III (83 eyes) received topical dorzolamide and 1% NaHa (Healon (R)) was used, and Group IV (83 eyes) did not receive any topical and 1% NaHa was used in operation. Mean postoperative IOPs were compared between groups. RESULTS. Eyes with 1.4% NaHa usage (18.2 +/- 9.2 mmHg) had higher mean postoperative IOPs than eyes with 1% NaHa usage (15.5 +/- 5.3 mmHg) (p=0.002). Mean postoperative IOPs were lower in eyes with dorzolamide application (15.6 +/- 7.2 mmHg) than in eyes without any medication (18.1 +/- 8.5 mmHg) both in eyes with 1.4% NaHa and 1% NaHa usage (p=0.003). Dorzolamide application caused an average 2.5 mmHg decrease in mean postoperative IOPs in both groups. CONCLUSIONS. Effects of OVDs on IOP rises after phacoemulsification surgery are closely related to their molecular structure. Increase in viscosity rendered higher postoperative IOP increments. However, topical dorzolamide application effectively reduced postoperative IOP increments in eyes with both Healon (R) and BD Visc (R) use.