Objective: To evaluate the ability to predict visual outcome after penetrating keratoplasty (PKP) in patients with pseudophakic corneal edema (PCE) or aphakic corneal edema (ACE) based on preoperative parameters available from the patient history and ocular examination. Design: Retrospective noncomparative case series. Participants: Forty-eight patients who underwent 59 PKP procedures for PCE between 1997 and 2000 by two cornea specialists. Methods: Medical records were retrospectively analyzed for variables in the history and ocular examination before PKP and visual outcome after PKP. Variables included age, gender, presence of diabetes or cardiovascular disease, method of intraocular lens (IOL) implantation during cataract surgery, vitreous loss during cataract surgery, time between cataract and PKP surgery, and maximal visual acuity reached after cataract surgery. The predictive value of each preoperative variable on post-PKP visual outcome was assessed using both univariate and multiple regression analyses. Main Outcome Measures: Statistical significance for the predictive value of each preoperative variable on post-PKP visual outcome. Results: Best-corrected visual acuity (BCVA) of 20/40 or better was achieved in 13 patients (27%). The strongest predictor of this outcome was implantation of a bag-fixated or sulcus-fixated IOL at the time of cataract surgery (P = 0.007; odds ratio, 15.8; 95% confidence interval, 1.2-208). Less significant variables included BCVA after cataract surgery, time between cataract surgery and PKP, and gender. Conclusions: In planning and advising patients with pseudophakic or aphakic corneal edema who are candidates for PKP, the method of IOL implantation during the cataract surgery is the single most significant predictor of visual acuity after corneal transplantation. Bag-fixated or sulcus-fixated posterior chamber IOL was associated with a better visual outcome than anterior chamber IOL, scleral-fixated posterior chamber IOL, or aphakia.