Purpose: To determine whether clear corneal phacoemulsification and the implantation of a copolymer acrylic (AcrySof. Alcon. Fort Worth, TX) intraocular lens will maintain the intraocular pressure (IOP) and number of medications in patients with a previous filtering bleb. Patients and Methods: This retrospective analysis included 69 consecutive patients with previous trabeculectomy who had a copolymer acrylic intraocular lens implanted during cataract surgery between 1995 and 1999 by a single surgeon (A.C.S.C.). Results: Mean IOP significantly decreased from 26.03 mm Hg (range, 14.5-70 mm Hg; n = 691) before trabeculectomy to 13.58 +/- 3.98 mm Hg (range, 5-24 mm Hg, n = 69) before the cataract extraction. After cataract extraction, the mean IOP increased significantly by 1.49 mm Hg(n = 67; P = 0.0013), by 1.85 mm Hg (n = 57, P = 0.0005). and by 1.01 mm Hg (n = 67; P = 0.042) after 6 months, after 1 year, and at the patient's last appointment. respectively. when patients whose pressures were purposely increased during cataract surgery were not included (n = 5), the mean increase at the last appointment was not significantly increased (0.54 mm Hg; n = 62; P = 0.25). The average number of antiglaucoma medications decreased from 2.93 (range, 1-5; n = 69) before trabeculectomy to 0.36 (ranee, 0-2 n = 69) before cataract surgery. This mean decreased to 0.34 (range, 0-2; n = 67, P = 0.8366) 6 months after cataract surgery and increased to 0.49 (range, 0-3; n = 57, P = 0.1029) and 0.62 (range, 0-3, n = 67; P = 0.0006) after 1 year and at the last appointment, respectively. Of the total study population, two (2.9%) patients required additional glaucoma surgery and 14 (20.3%) patients required additional antiglaucoma medications as compared with their precataract levels. Conclusions: Clear corneal phacoemulsification and the implantation of a copolymer acrylic (AcrySof. Alcon) posterior chamber intraocular lens statistically increased the number of medications and IOP of patients in our study. These increases, although statistically significant, did not cause a clinically significant deterioration in IOP control.