Homeostatic response of intraocular pressure in the early period after sutureless phacoemulsification

PURPOSE: To determine the homeostatic response of postoperative intraocular pressure (IOP) by analyzing postoperative IOP trends after sutureless phacoemulsification. SETTING: Asan Medical Center, Seoul, South Korea. DESIGN: Comparative case series. METHODS: Normotensive eyes were treated with sutureless phacoemulsification with in-the-bag posterior chamber IOL (PC IOL) implantation. The patients were randomly divided into 3 groups according to the intended immediate postoperative IOP as follows: Group 1, IOP less than 10 mm Hg; Group 2, IOP 10 to 21 mm Hg; Group 3, IOP over 21 mm Hg. The surgeon intentionally attempted supranormal, normal, or subnormal pressurization. The IOP was measured immediately after surgery and 2 hours, 4 hours, 1 day, 1 week, and 1 month postoperatively. RESULTS: Group 1 included 88 eyes (27.8%), Group 2 included 130 eyes (41.2%), and Group 3 included 98 eyes (31.0%). The mean IOP immediately after surgery was 6.4 mm Hg ± 2.0 (SD), 14.5 ± 3.2 mm Hg, and 27.0 ± 4.6 mm Hg, respectively, with significant differences between the 3 groups (P<.05). However, the IOP values were nearly normalized in the 3 groups 2 to 4 hours postoperatively. Twenty-eight eyes (8.9%) had an IOP lower than 5 mm Hg immediately after surgery in the absence of incision leakage. There were no postoperative complications related to hypotony. Thirty-one eyes (9.8%) had an IOP of at least 30 mm Hg immediately after surgery; the IOP normalized by 1 day postoperatively. CONCLUSION: In normal eyes that had uneventful sutureless phacoemulsification with in-the-bag PC IOL implantation, immediate postoperative high or low IOP did not affect the return to baseline levels.