Improved Femtosecond Laser-Assisted Phacoemulsification of Hard Nucleus Cataract

Abstract

Purpose: The development and clinical study of improved femtosecond laser-assisted phacoemulsification (PE) technology of hard nucleus cataract.Patients and methods. Improved femtosecond laser-assisted PE of hard nucleus cataract performed in 83 patients (93 eyes) (1st group), known femtosecond laser-assisted PE technique performed in 72 patients (78 eyes) (2nd group), torsional PE performed in 81 patients (89 eyes) (3rd group). The degree of intraoperative myosis, effective ultrasound time, corneal endothelial cell loss were evaluated in all groups.Results. Femtosecond laser-assisted PE is an effective technique for hard nucleus cataract removal, which can significantly reduce the energy ultrasonic load on the eye tissue. The proposed method for the instillation of prostaglandin synthesis inhibitors and the observance of the minimum possible interval between the first and second stages of the operation can prevent significant intraoperative narrowing of the pupil. A significant narrowing of the pupil by more than 2 mm after the femtolaser stage was noted in 7 (7.5 %) cases in the 1st group of patients, in 15 (16.9 %) cases in the 2nd group, in 5 (6.4 %) cases in the 3rd group. The results of the study has shown a significant decrease in the effective ultrasound time for a femtosecond laser-assisted PE compared with a torsional PE. The effective ultrasound time was in the 1st group (improved technology of femtosecond laser-assisted PE) — 3.81 ± 0.75, in the 2nd group (known technology of the femtosecond laser-assisted PE) — 5.23 ± 1.07 s (p < 0.05), in the 3rd group (OZil technology) — 8.67 ± 1.83 s (p < 0.05). The decrease in the effective ultrasound time has become a determining factor in reducing the loss of corneal endothelial cells in both femtosecond laser-assisted PE technologies compared to torsional PE. The average loss of corneal endothelial cells 3 months after surgery was 8.7 ± 1.8 % in the 1st group, 10.3 ± 2.1% in the 2nd group, 13.5 ± 2.7 % (p < 0.05) in the 3rd group of patients.Conclusion. The proposed improved technology contributes to the solution of some problems that characterize femtosecond laser-assisted PE, and also helps to reduce the effective ultrasound time and the loss of corneal endothelial cells.