Three and Five Year Changes in Intraocular Pressures After Clear Corneal Phacoemulsification in Open Angle Glaucoma Patients, Glaucoma Suspects, and Normal Patients

Abstract

This study evaluates the change in intraocular pressure (IOP) and glaucoma medication requirements after clear corneal phacoemulsification in open angle glaucoma patients, glaucoma suspects, and normal patients at 3 years and last follow-up (mean 5 y). This study represents a retrospective analysis of patients who had clear corneal phacoemulsification and at least 3 years of follow-up. The patients were classified into 3 groups: glaucoma (G), glaucoma suspects (GS), and no glaucoma (NG). No patient had a history of previous intraocular surgery. Single factor analysis of variance, Fisher exact tests, 2-tailed paired Student t tests and Kaplan-Meier analysis were applied. Forty-eight patients (55 eyes) in the glaucoma group, 41 patients (44 eyes) in the GS group, and 59 patients (59 eyes) in the NG group met the above criteria. At 3 years follow-up IOP was significantly decreased in all groups; (G) group decreased 1.4+/-3.3 mm Hg (P = 0.0025), GS 1.4+/-4.2 mm Hg (P = 0.004), and NG 1.7+/-3.1 mm Hg (P = 0.0005). At the final follow-up visit (mean near 5 y for all groups) the IOP was significantly decreased in all groups, (G) group 1.8+/-3.5 mm Hg (P = 0.005), GS 1.3+/-3.7 mm Hg (P = 0.025), and NG 1.5+/-2.5 mm Hg (P < 0.0001). The number of preoperative and postoperative glaucoma medications in the (G) group did not show any significant change at 3 and 5 years (P = 0.36, P = 0.87). Kaplan-Meier analysis shows that at 3 years, 85% of the (G) group, 81% of GS, and 90% of the NG had IOPs less than or equal to their preoperative IOP, with the same number of glaucoma medications or less. At 5 years the percentages were 76%, 79%, and 85%, respectively. This study demonstrates that cataract removal by clear cornea phacoemulsification in glaucoma patients, glaucoma suspects, and normal patients results in a small but significant decrease in IOP that is sustained at 3 years and a mean of 5 years in all groups. This study does not imply that cataract removal by phacoemulsification is a substitute for a combined procedure but may be an appropriate procedure for certain patients based on medication requirements and extent of optic nerve damage.