To investigate the morphology and ultrastructural and analyze the capculorhexis morphological parameter of femtosecond laser assisted anterior capsulotomy.

A prospective case-control design was used to observe the clinical data of 25 cases (40 eyes) of cataract patients who received surgical treatment from January 2015 to October in Chongqing all ophthalmology hospital. Among them, 12 cases (20 eyes) of femtosecond laser assisted capsulorhexis wereused as experimental group, and 13 cases (20 eyes) with manual capsulorhexis as control group. The two groups of patients were removed intraocular capsulorhexis after removal of lens anterior capsule to make electron microscope specimens. The continuity, smoothness and thickness of the capsule edge were observed. The baseline parameters and morphological parameters of the anterior capsule were described by mean±standard deviation (±s), and the two were compared by t-test. The Kruskal-Wallis H rank sum test was used to compare the capsule smoothness. Using digital slit lamp to gather anterior segment pictures at 1 week, 1 month and 3 months postoperatively, analysis images to calculate capsulorhexis morphological parameters.

The smooth degree and thickness of the free anterior capsule edge of the two groups were statistically different, and the low magnification capsule smoothness test group was better than the control group, but the difference was statistically significant (Z=-3.79, -4.54; P<0.05), and the membrane thickness test group was less than the control group (t=16.62, P <0.5). The comparison of the capsule oral parameters between the experimental and control groups showed that the differences in the vertical diameter between the two groups were not found to be statistically significant (F=0.85, P>0.05); however, the level diameter, roundness and minimum distance of the two groups were the minimum distance, the maximum distance and coverage of the optical part of the intraocular lens in the capsule margin (F=4.45, 5.51, 6.76, 8.92, 7.99; P<0.05). Among them, the test group was larger than the control group except the maximum distance test group. The intra group comparison (1 week, 1 months, 3 months) showed that there was no significant difference in the horizontal diameter, roundness and coverage (F=0.92, 0.67, 0.85; P>0.05), but the differences in vertical diameter, minimum distance and maximum distance were statistically significant (F=4.58, 5.21, 5.97; P<0.05). Among them, the maximum distance and minimum distance increase gradually, while the vertical diameter gradually decreases. There was no correlation between the diameter and coverage of the two groups of anterior capsular orifice.

This study showed that the degree of roundness and the continuity of the anterior capsule in morphological the laser group were significantly better than that of the manual group. The parameter of the anterior capsule showed that laser-created capsulotomies was more regular and more continuous than that of manually created. Laser-created capsuloto-mies covered the IOL more effective in 3 months after surgery.

Femtosecond laser; Cataract; Anterior capsule; Scanning electron microscope; Microstructure