We evaluated the pre- and postoperative intraocular pressure (IOP) levels of 498 patients, to determine whether IOPs are affected over a 10-year period. All surgeries were performed by the same surgeon using phacoemulsification and aspiration (PEA) with posterior chamber intraocular lens (PCIOL) implantation. The mean preoperative IOP was 12.2 +/- 4.0 mm Hg, and the mean postoperative IOPs were not affected for 10 years. However, when the preoperative IOP was over 20 mm Hg, a significant decrease was achieved without glaucoma surgery. When the preoperative IOP was under 10 mm Hg, the IOP significantly increased. PEA with implantation of a PCIOL provides an excellent chance for improved intraocular tension control, providing that the surgery is properly performed.