Long Term Intraocular Pressure Change after Phacoemulsification with Intraocular Lens Implantation in Glaucomatous and Non-glaucomatous Patients, Panyananthaphikkhu Chonprathan Medical Center

Abstract

OBJECTIVES: To evaluate long term intraocular pressure (IOP) following phacoemulsification with intraocular lens implantation in glaucoma and normal patients. MATERIAL AND METHODS: A retrospective analysis of 208 patients who had undergone phacoemulsification by the same surgeon at Panyananthaphikkhu Chonprathan Medical Center between February 2011 and February 2015. The patients were divided into 3 groups: no glaucoma (NG), primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). Preoperative and postoperative best-corrected visual acuity (VA), IOP, and the number of glaucoma medications were recorded. IOP was evaluated before surgery and post-surgery for 1 month, 3 months, and last follow-up (mean 40 months). Repeated measure ANOVA and Post hoc by Scheffe test was used to compare IOP between 3 groups over time. Paired t-test was conducted to determine the relationship between preoperative IOP and postoperative IOP. The p-value of less than 0.05 was set for statistically significant. RESULT: There were 86 patients in the NG group, 61 patients in the POAG group, and 61 patients in the PACG group. The first month saw the mean IOP significantly decrease in all groups (p < 0.001): NG group decreased 2.06 ± 2.21mmHg, POAG group 2.97 ± 3.25 mmHg, and PACG group 3.18 ± 2.77 mmHg. At 3 months the mean IOP was significantly decrease in all group(p < 0.001):NG group decreased 2.44 ± 2.14 mmHg, POAG group 2.72 ± 2.73 mmHg, and PACG group 3.51 ± 2.78 mmHg. At the final follow-up visit the mean IOP still significantly decrease in all group (p < 0.001): NG group decreased 1.45 ± 1.96 mmHg, POAG group 2.17 ± 2.98 mmHg, and PACG group 3.32 ± 2.84 mmHg. Eye with higher preoperative IOP has the greatest IOP- lowering effect. The number of glaucoma medication slightly decreased even though they are both the groups of open and closed angle (p = 0.002 VS p < 0.001). Visual acuity was significantly improved after phacoemulsification in all group. CONCLUSION: Phacoemulsification not only improves the visual acuity but also provides a long term significant decrease in IOP and glaucoma medication. This IOP-lowering effect is proportional to preoperative IOP.