A system for preoperative stratification of cataract patients according to risk of intraoperative complications: a prospective analysis of 1441 cases

Aim: To devise a simple, robust scoring system for assessing the risk of intraoperative complications in patients undergoing cataract surgery. Methods: 1441 consecutive patients undergoing phacoemulsification cataract surgery were assessed preoperatively according to weighted criteria. According to the points of risk they accumulated using this system, the patients were preoperatively allocated to one of four risk groups. Data were prospectively collected on the occurrence of intraoperative complications and entered into a computerised database. The total rate of intraoperative complications for each risk group as well as the rate of each reported complication for each risk group were calculated. Results: The rate of intraoperative complications increased in frequency through the risk groups: 1 = 4.32%, 2 = 7.45%, 3 = 13.48%, and 4 = 32.00% ( p< 0.001). Furthermore, the following complications also increased in frequency through the risk groups in their own right ( p< 0.05 in each case): posterior capsule rupture, vitreous loss, incomplete capsulorrhexis, zonule dehiscence, wound burn/leak, and lost nuclear fragment into vitreous cavity. Conclusion: These results suggest that candidates for cataract surgery can be simply and uniformly assessed preoperatively and categorised to a "risk group'' according to their risk of intraoperative complications. This allows for: ( 1) individualised counselling on the chances of operative complications, ( 2) meaningful comparisons between national complication rates and those of individual units or surgeons, and ( 3) better selection of cases suitable for instruction.