Capsulotomy Proficiency Index As An Objective Indicator For Continuous Circular Capsulorhexis Evaluation

Continuous circular capsulorhexis (CCC) quality affects posterior capsule opacification and visual outcomes after cataract surgery. We developed a novel metric, the capsulotomy proficiency index (CPI), to objectively evaluate the CCC manipulation during cataract surgery.

Observational experimental study.

We developed a self-design code using MATLAB software to outline the motion trail of the capsulorhexis forceps, the eye motion amplitude, the limbus center, the CCC profile, the CCC center, the number of grasps, and the CCC operating time. Considering the weight of each parameter as mentioned above, an integrated CPI value was used to evaluate each CCC surgical video.  

This study included two surgeons from two hospitals with different total cataract surgery volumes (surgeon A: less than 500 cases, surgeon B: more than 30,000 cases). Ten CCC videos from each surgeon during the same working period were randomly selected. A student t-test was used to compare the mean CPI from the two groups. Surgeon A demonstrated a significantly lower CPI mean value than surgeon B (0.324±0.278 & 0.899±0.105), indicating a significant difference in surgical level. 

As an objective CCC surgical evaluation value, the CPI could reflect the surgical level difference.