Effect of Phacoemulsification on Intraocular Pressure in Healthy Subjects and Glaucoma Patients

BACKGROUND: We investigated how cataract surgery might influence long-term intraocular pressure (IOP) change in both healthy subjects and glaucoma patients. METHODS: A retrospective analysis of patients who had had clear corneal phacoemulsification with a minimum of 12 months of follow up was performed. Glaucoma patients with medically controlled open-angle glaucoma and healthy subjects with no glaucoma were included in the analysis. The change of IOP after phacoemulsification and factors associated with postoperative IOP change were investigated. RESULTS: In total, 754 eyes of 754 patients, specifically 106 patients with glaucoma and 648 patients with no glaucoma (i.e., healthy subjects) were enrolled. The phacoemulsification effected a reduction of IOP: 1.03 ± 3.72 mmHg in healthy subjects and 1.08 ± 3.79 mmHg in glaucoma patients at postoperative 1 year (P = 0.656). There were negative coefficients of IOP until 1 year of follow up (all P < 0.001), but the IOP change gradually showed a less steeply decreasing slope (correlation coefficient: −0.993), compared with those for 1 week and 1 month of follow up (correlation coefficients: −1.893 and −1.540, respectively). In the multivariate analysis, age and preoperative IOP showed significant associations with postoperative IOP change (regression coefficients: −0.034 and 0.419 respectively, all P < 0.001). CONCLUSION: Phacoemulsification resulted in IOP reduction, which effect regressed in healthy subjects and glaucoma patients over the course of long-term follow up. Therefore, long-term monitoring of IOP change is needed. In cases of higher preoperative IOP and young patients, phacoemulsification alone is a reliable option for IOP control.