Aim: To evaluate the effect of phacoemulsification with intraocular lens implantation in eyes with pre-existing trabeculectomy.
Methods: This prospective single-center clinical study evaluated intraocular pressure in 60 eyes of 60 patients who underwent phacoemulsification and implantation of a foldable intraocular lens after a previous successful trabeculectomy. Patients who had a trabeculectomy more than one year prior to the study were included. Intraocular pressure, number of antiglaucoma medications, bleb appearance, and visual acuity were recorded preoperatively, and at each follow-up examination and 12 months after phacoemulsification.
Results: The mean intraocular pressure before phacoemulsification was 12.42 mmHg (SD, 4.60 mmHg), which increased to 14.98 mmHg (SD, 4.18 mmHg), 14.47 mmHg (SD, 3.58 mmHg), 15.44 mmHg (SD, 3.60 mmHg), and 15.71 mmHg (SD, 3.47 mmHg) after one, three, six, and 12 months, respectively. At each follow-up visit, the mean IOP was significantly higher than the preoperative value (p < 0.001, p = 0.015, p ≤ 0.001, and p = 0.001 at month one, three, six, and 12, respectively). The mean preoperative best-corrected visual acuity was 0.98 logMAR (SD, 0.44 logMAR) and the mean postoperative best-corrected visual acuity at 12 months was 0.20 logMAR (SD, 0.21 logMAR) [p = 0.0001]. The mean preoperative number of antiglaucoma medications used was 0.57 (SD, 0.63), which increased to 0.65 (SD, 0.63 ), 0.70 (SD, 0.72 ) 0.68, (SD, 0.70), and 0.67 (SD, 0.77 ) at one, three, six, and 12 months, respectively, but there were no statistically significant differences. Bleb size decreased clinically after phacoemulsification. Nineteen of 60 eyes (32%) developed fibrosis of bleb with decreased bleb size.
Conclusion: Phacoemulsification with intraocular lens implantation significantly increased intraocular pressure and increased the number of antiglaucoma medications in eyes with pre-existing functioning filtering blebs.