PURPOSE: To quantify the macular edema induced by intracameral mydriatics in phacoemulsification surgery. SETTING: University hospital eye clinic, Umeå, Sweden. METHODS: In a randomized study of 22 patients, 11 patients were given 150 muL of a mixture of phenylephrine 1.5% and lidocaine 1% intracamerally for mydriasis and anesthesia. In a control group (n = 11), conventional topical mydriatics and intracameral lidocaine were given. Multiple preoperative, intraoperative, and postoperative variables were recorded. RESULTS: There were no differences in macular edema between the 2 treatments. A correlation was seen between macular edema and impaired visual acuity 1 week postoperatively. On the first postoperative day, a similar correlation was seen between corneal edema and the degree of visual improvement. CONCLUSIONS: Intracameral lidocaine and phenylephrine for mydriasis and anesthesia did not induce more significant macular edema than the standard regimen of topical mydriatics plus intracameral lidocaine. Macular edema limited visual improvement 1 week after phacoemulsification, while corneal edema appeared to have a larger effect immediately after surgery.