[Comparative analysis of the clinical application of two femtosecond laser-assisted cataract operation platforms]

Objective: To evaluate the operability and clinical application effects of femtosecond laser-assisted cataract surgery systems of LenSx and LenSAR. Methods: This was a randomized controlled study. A total of 86 patients (90 eyes) who underwent femtosecond laser-assisted cataract surgery in Wuhan Aier Eye Hospital from April 2018 to November 2018 were enrolled and divided into two groups randomly, including 44 patients (45 eyes) in the LenSx group and 42 patients (45 eyes) in the LenSAR group. During the operation, the following observation indexes were obtained. Operational indicators included the number of docking attempts, anterior capsulotomy time, nucleus pre-treatment time, total femtosecond laser emission time, and total vacuum suction duration. Clinical outcome indicators included changes in the patient's intraocular pressure during femtosecond laser surgery, the rate of subconjunctival hemorrhage, capsulotomy integrity (yes/no), roundness and centricity of the anterior capsule opening (yes/no), the rate of anterior capsule opening tear, and the rate of posterior capsule rupture. The t-test, rank-sum test or chi-square test were used for statistical analysis. Results: There were no significant differences between groups in the age and the lens density (both P>0.05). The number of docking attempts in the LenSx group was 1 (1 to 4) and in the LenSAR group was 1 (1 to 2); there was statistically significant difference (Z =-2.23, P<0.05). The difference in the anterior capsulotomy time between the two groups was statistically significant [13.00 (10.00 to 22.00) s compared with 3.00 (1.00 to 3.00) s, Z=-8.71, P<0.05]. The femtosecond laser pre-nucleation time and total femtosecond laser emission time of the LenSx group were (16.67±3.36) s and (30.49±3.53) s, and those of the LenSAR group were (12.38±4.36) s and (15.36±4.29) s, respectively; the differences between the two groups were statistically significant (t=-5.23, -18.26; both P<0.05). The total vacuum suction duration in the LenSx group was (97.23±19.96) s, shorter than that in the LenSAR group [(123.76±16.81) s] (t=6.82, P<0.05). The intraocular pressure after femtosecond laser surgery in both groups was higher than that before surgery. The increase of intraocular pressure in the LenSAR group was (5.64±5.42) mmHg (1 mmHg=0.133 kPa), higher than that in the LenSx group [(2.99±4.66) mmHg] (t=-2.49, P<0.05). The rate of subconjunctival hemorrhage in the LenSx group was 33.3% (15/45), while it was 8.9% (4/45) in the LenSAR group; the difference between the two groups was statistically significant (χ²=6.67, P<0.05). There were no significant differences between groups in capsulotomy integrity, roundness and centricity of the anterior capsule opening, the rate of anterior capsule opening tear, and the rate of posterior capsule rupture (all P>0.05). Conclusion: The docking process of the LenSAR system is convenient, and there is less subconjunctival hemorrhage; the total vacuum suction duration of LenSx is short, and the increase of intraocular pressure is low. (Chin J Ophthalmol, 2020, 56: 530-535).