# Examination of phacoemulsification tips after different numbers of cataract surgeries

## TL;DR

This study compares phacoemulsification tips used in cataract surgeries using different techniques and finds that tip wear increases with use and varies by surgical method.

## Contribution

The study introduces a novel comparison of phacoemulsification tip wear using atomic force microscopy and surgical performance metrics across two surgical techniques.

## Key findings

- Roughness of phacoemulsification tips increases with the number of uses.
- The divide and conquer technique causes less microscopic damage and requires less ultrasound energy.
- Significant correlations were found between surgical parameters like area% and ultrasound energy metrics.

## Abstract

To compare unused phacoemulsification tips and those used different times with different techniques of cataract surgery (divide and conquer and chop), in vivo phacoemulsifications were performed with tips of different numbers of operation. These were compared with the same number of sterilized-only and unused tips with the help of an atomic force microscope. Comparison of roughness values (Sa, Sq), geometric and measurable flange length and surface was also performed (profile length %, area %). The differences between the parameters that can be measured during surgery (average ultrasound percentage, US ave %, Average Phaco Time, APT) were also analyzed. We found significant correlations between age and lens hardness (p = 0.0045), area % and APT (p = 0.03), between area % and US ave% (p = 0.03) and also between the two surgical techniques in terms of area% (p = 0.04) and US ave % (p < 0.01). Roughness increased with the number of uses. An increase in profile length% can be observed up to the twentieth operation. This can result from scratches and microscopic damages and also from abrasion and possible material additions on the surface of the needles. The divide and conquer technique causes less microscopic damage to the surface, and smaller average US energy is required during surgery.