Effects of Femtosecond Laser-Assisted Cataract Pretreatment on Pupil Diameter: A Comparison Between Three Laser Platforms

PURPOSE: To assess pupil diameter before and after femtosecond laser-assisted cataract surgery (FLACS) pretreatment and compare the outcomes of three laser platforms. METHODS: This prospective observational case series included consecutive patients scheduled to undergo cataract extraction using FLACS between August 2013 and February 2015. All eyes received FLACS pretreatment using three laser platforms: LenSx (Alcon Laboratories, Inc., Fort Worth, TX), Catalys (Abbott Medical Optics Inc., Santa Ana, CA), and Victus (Bausch & Lomb, Inc., Rochester, NY). The same protocol for preoperative medical mydriasis was used for all patients, and pupil diameter was assessed immediately before and 3 minutes after FLACS using a surgical ruler. RESULTS: A total of 198 eyes of 161 patients were included in the study. Mean pupillary miosis was 1.42 ± 1.26 mm for the LenSx, 0.66 ± 0.89 mm for the Catalys, and 0.14 ± 0.34 mm for the Victus groups. Furthermore, 8 of the 198 eyes (4.0%) demonstrated a pupil diameter of less than 5 mm after FLACS and 48 eyes (24.24%) demonstrated a pupil diameter of 6 mm or less. There was a statistically significant decrease in pupil diameter for all groups individually (P < .05). There was also a statistically significant difference among the three groups (P < .05), with LenSx inducing the highest degree of miosis, followed by Catalys, and finally Victus. A correlation between the pupil diameter before FLACS and degree of FLACS-induced miosis was demonstrated (P < .05), with larger pupil diameter before FLACS associated with greater miosis. CONCLUSIONS: FLACS pretreatment seems to induce significant pupillary miosis with all laser platforms assessed in this study. The decrease in pupil diameter after FLACS reached clinical significance for cataract extraction (< 5 mm) in 4.0% of cases, whereas 20.2% of eyes demonstrated small pupil diameter (≤ 6 mm) after FLACS pretreatment.