Safety of femtosecond laser-assisted cataract surgery: assessment of aqueous humour and lens capsule

Abstract

Purpose: To investigate the effect of femtosecond laser-assisted cataract surgery (FLACS) on aqueous humour and lens capsule.

Methods: This prospective randomized comparative study enrolled 19 eyes that underwent FLACS as the trial group and 20 eyes that underwent conventional phacoemulsification as the control group. The femtosecond laser platform (LLS-fs 3D; LensAR, Orlando, FL, USA) was used to generate capsulotomy (laser energy 8 μJ) and lens fragmentation (laser energy 10 μJ). Morphology of the cutting edge and cells of anterior capsule was assessed by light microscopy. The proteins in the aqueous humour were identified by mass spectrometry (Ultraflex III TOF/TOF; Bruker Dalton, Bremen, Germany). Electrolyte in the aqueous humour was detected by a chemistry analyzer (Aeroset Clinical Chemistry Analyzer; Abbott Laboratories, Abbott Park, IL, USA).

Results: The cutting edge of anterior capsule was saw-tooth-shaped under magnification of 200× and 400× in the trial group, while it was smooth in the control group. Intact cells were found in the boundary area next to the cutting edge of anterior capsule in both groups. β-Crystallin B1, γ-crystallin S and transferrin were detected in the aqueous humour in the trial group. The concentrations of K⁺ , Na⁺ and Cl^- in the aqueous humour in the trial group differed significantly from those in the control group (p = 0.02, 0.03 and 0.04, respectively).

Conclusion: Femtosecond laser-assisted cataract surgery (FLACS) causes release of transferrin and crystallin from lens to aqueous humour and results in significant changes in the concentrations of K⁺ , Na⁺ and Cl^- in aqueous humour. However, these changes due to FLACS have no clinical significance or toxicity.

Keywords: aqueous humour; cataract; femtosecond laser; lens capsule.