Comparison of ultrastructure of anterior lens capsule flap derived from manual capsulorrhexis and femtosecond laser-assisted capsulotomy

Abstract

Objective To compare the ultrastructure of anterior lens capsule flap derived from manual capsulorrhexis and femtosecond laser-assisted capsulotomy. Methods Twenty-eight eyes of 28 cases with cataract aged from 55 to 65 years old were collected for traditional phacoemulsification and intraocular lens implantation. These patients included 17 males and 11 females. In which, 16 flaps of anterior lens capsule were derived from manual continuous circular capsulorhexis and 12 flaps were derived from femtosecond laser-assisted capsulotomy. The anterior lens capsule flaps were subdivided into two groups randomly, and were examined by light microscopy(LM) and transmission electron microscope(TEM) respectively. The ulrastructure of the flap edge and the tissue near the flap edge were examined carefully. Results The flap derived from manual capsulorrhexis had smooth edge, no cell destruction was found, and the cells fully filling into the cutting edge were observed under LM and TEM examination. The anterior capsule flap derived from femtosecond laser-assisted capsulotomy showed an approximate 60 μm banded area of cell degeneration and necrosis, with dentiform prominences at the edge of the capsule flaps, and no cell structrue was observed at this area. Conclusion The flap by femtosecond laser-assisted capsulotomy has a rougher edge, with banded degeneration and necrosis area at the cutting border, which may be related to the shock wave caused by strong instant power of femtosecond laser. Key words: Phacoemulsification, cataract; Femtosecond laser-assisted capsulotomy; Continuous circular capsulorhexis; Anterior lens capsule flap; ultrastructure