Avoidable adverse events in cataract surgery: a national 11-year study of error types, care process patterns, and patient harm.

PURPOSE: This study aimed to systematically classify and analyse avoidable adverse events following cataract surgery in Sweden, with a focus on identifying the most frequent error types, their patterns across the care process, and areas for targeted patient safety improvement.

METHODS

In a retrospective cohort study 371 avoidable adverse events related to cataract surgery (1 January 2010-31 December 2020) were analysed using data from Löf, Sweden's national patient insurance company, together with patients' medical records. All events were confirmed as preventable through expert medical review.

RESULTS

The most frequent adverse events were endophthalmitis (24%, n = 90), incorrect intraocular lens (IOL) power selection (10%, n = 37), inadequate cortex or lens removal (8%, n = 29), and iatrogenic corneal injury (7%, n = 26). Endophthalmitis, failure in postoperative monitoring, and inadequate preoperative evaluation, were associated with higher levels of permanent medical impairment, with ≥ 16% medical invalidity in 20-23% of affected patients. In contrast, deviations such as incorrect IOL power selection and IOL misplacement were more often linked to short-term outcomes or mild medical impairment.

CONCLUSION

Endophthalmitis was the most common adverse event and was associated with the highest levels of permanent medical impairment. However, avoidable adverse events following cataract surgery extend beyond intraoperative technical errors and occur throughout the entire care process. Failures in preoperative evaluation and postoperative monitoring were most strongly associated with lasting visual harm. The mechanisms of avoidable harm identified are highly relevant across all healthcare settings performing high-volume cataract surgery.