Combined Burst Mode versus Torsional Mode Phacoemulsification for Patients with Hard Nuclear Cataracts: A Prospective Comparative Cohort Study

Purpose To evaluate the hard nuclear cataract surgery outcomes by comparing the combined burst mode and continuous torsional mode conducted of Centurion Vision System. Methods Prospective comparative cohort study. Based on the Emery-Little classification, this study assigned cataract patients with nuclear density grade III to V into two groups: the combined mode group (Group A) and the torsional mode group (Group B). Endothelial cell density (ECD), central corneal thickness (CCT), and best-corrected distance visual acuity (BCVA) were evaluated at different time intervals, including 1 day, 1 week, 1 month, and 3 months. Results 207 patients: 100 in the group A and 107 in the group B. Patients in group A with severe nuclei experienced lower cumulative dissipated energy (p = 0.007) and shorter ultrasound time (p < 0.001). Both groups exhibited a decrease in ECD after surgery, but the decrease was comparatively lower among group A patients with severe nuclei (p < 0.05). There was a notable increase in the CCT in both groups at the 1-day and 1-week time points compared to the baseline values (p < 0.001). Changes in CCT were significantly greater in group B at 1-day (p < 0.001), 1-week (p = 0.002), and 1-month (p = 0.004) intervals among patients with severe nuclei. Conclusion Burst torsional combined with longitudinal ultrasound can be more effective for harder nuclei phacoemulsification than the continuous torsional ultrasound. Trial Registration This study was conducted in accordance with the Declaration of Helsinki and was approved by the Institutional Review Board of Fudan University’s Eye & ENT Hospital. This study was registered as a clinical trial (number: NCT06991374).