Refractive effect of capsular bag lens placement with the capsulorhexis technique

Fifty consecutive patients who had cataract extraction and intraocular lens implantation with a can-opener anterior capsulotomy were compared to 50 patients who had a continuous tear capsulotomy and confirmed capsular bag lens placement. The actual versus the predicted postoperative refraction was calculated with both the SRK II and the Holladay lens power formulas. With both formulas, the capsulorhexis patients required a spectacle correction 0.43 (or 0.44) diopter greater than the can-opener patients when the same A-constant or surgeon factor was used. The recalculated A-constant was 118.23 for the can-opener patients and 118.76 for the capsulorhexis patients; the manufacturer's recommended A-constant was 118.3. The results were statistically significant.