Abstract:This study was to estimate refractive status of the second eye of those undergo bilateral cataract surgery based on the first-operated eye, and to evaluate the refractive error (RE) in the second eye after correcting 50% of the first-operated eye’s error when it exceeded ±0.50 diopter (D). In this prospective study, 80 patients were scheduled for cataract surgery in the second eye, who underwent cataract surgery in first eye 1-3mo previously. The RE of each eye postoperatively was determined according to SRK/T formula. When the first-eye refractive error (FERE) exceeded ±0.5 D, the intraocular lens (IOL) power of the second eye was adjusted 50% of the FERE. The second-eye refractive error (SERE) was measured 1mo after surgery. The FERE exceeded -0.50 D in 12 eyes (-0.675±0.16 D), and the adjusted SERE was -0.322±0.73 D (P<0.05). The FERE exceeded +0.50 D in 8 eyes (1.533±1.14 D), and the adjusted SERE was 0.168±1.36 D (P<0.05). The unadjusted SERE in 60 cases remained -0.38 to 0.42 D when the FERE within ±0.05 D. This prospective study confirmed that the prediction of the second eye could be improved by correcting 50% of FERE when this error exceeded ±0.50 D.