Comparison of effective phacoemulsification time and corneal endothelial cell loss using 2 ultrasound frequencies

To compare 2 ultrasound (US) frequencies for phacoemulsification for moderate to hard cataract to determine a frequency that makes phacoemulsification safer and more efficacious.

Post Graduate Institute of Medical Education and Research, New Delhi, India.

Randomized controlled trial.

Patients with grade 4.0 to 6.9 senile cataract were randomized to 2 groups. Group A had lower frequency (28 kHz) phacoemulsification, and Group B had higher frequency (42 kHz) phacoemulsification. The effective phacoemulsification time (EPT) and estimated fluid usage (EFU) were compared intraoperatively. The endothelial parameters were assessed over 1 year.

Both groups comprised 80 patients. The groups were matched for age (P = .533), sex (P = .263), and nuclear grade (nuclear color, P = .496; nuclear opalescence, P = .622). Group B had significant reductions in EPT (P = .008) and EFU (P = .004) compared with Group A. Postoperatively, the endothelial cell density (ECD) was significantly higher in Group B at 1 month (P = .004), 3 months (P = .003), 6 months (P = .004), 9 months (P = .002), and 1 year (P = .003). The percentages of ECD loss were also significantly lower in Group B; the difference was statistically significant up to 1 year postoperatively even after adjustments for age, grade of cataract, EPT, and EFU.

Higher frequency phacoemulsification was associated with a lower EPT and EFU as well as better endothelial preservation than a lower frequency.