Health Technology Assessment (Jan 2021)
Femtosecond laser-assisted cataract surgery compared with phacoemulsification: the FACT non-inferiority RCT
Abstract
Background: Cataract surgery is one of the most common operations. Femtosecond laser-assisted cataract surgery (FLACS) is a technique that automates a number of operative steps. Objectives: To compare FLACS with phacoemulsification cataract surgery (PCS). Design: Multicentre, outcome-masked, randomised controlled non-inferiority trial. Setting: Three collaborating NHS hospitals. Participants: A total of 785 patients with age-related cataract in one or both eyes were randomised between May 2015 and September 2017. Intervention: FLACS (n = 392 participants) or PCS (n = 393 participants). Main outcome measures: The primary outcome was uncorrected distance visual acuity in the study eye after 3 months, expressed as the logarithm of the minimum angle of resolution (logMAR): 0.00 logMAR (or 6/6 if expressed in Snellen) is normal (good visual acuity). Secondary outcomes included corrected distance visual acuity, refractive outcomes (within 0.5 dioptre and 1.0 dioptre of target), safety and patient-reported outcome measures at 3 and 12 months, and resource use. All trial follow-ups were performed by optometrists who were masked to the trial intervention. Results: A total of 353 (90%) participants allocated to the FLACS arm and 317 (81%) participants allocated to the PCS arm attended follow-up at 3 months. The mean uncorrected distance visual acuity was similar in both treatment arms [0.13 logMAR, standard deviation 0.23 logMAR, for FLACS, vs. 0.14 logMAR, standard deviation 0.27 logMAR, for PCS, with a difference of –0.01 logMAR (95% confidence interval –0.05 to 0.03 logMAR; p = 0.63)]. The mean corrected distance visual acuity values were again similar in both treatment arms (–0.01 logMAR, standard deviation 0.19 logMAR FLACS vs. 0.01 logMAR, standard deviation 0.21 logMAR PCS; p = 0.34). There were two posterior capsule tears in the PCS arm. There were no significant differences between the treatment arms for any secondary outcome at 3 months. At 12 months, the mean uncorrected distance visual acuity was 0.14 logMAR (standard deviation 0.22 logMAR) for FLACS and 0.17 logMAR (standard deviation 0.25 logMAR) for PCS, with a difference between the treatment arms of –0.03 logMAR (95% confidence interval –0.06 to 0.01 logMAR; p = 0.17). The mean corrected distance visual acuity was 0.003 logMAR (standard deviation 0.18 logMAR) for FLACS and 0.03 logMAR (standard deviation 0.23 logMAR) for PCS, with a difference of –0.03 logMAR (95% confidence interval –0.06 to 0.01 logMAR; p = 0.11). There were no significant differences between the arms for any other outcomes, with the exception of the mean binocular corrected distance visual acuity with a difference of –0.02 logMAR (95% confidence interval –0.05 to 0.00 logMAR) (p = 0.036), which favoured FLACS. There were no significant differences between the arms for any health, social care or societal costs. For the economic evaluation, the mean cost difference was £167.62 per patient higher for FLACS (95% of iterations between –£14.12 and £341.67) than for PCS. The mean QALY difference (FLACS minus PCS) was 0.001 (95% of iterations between –0.011 and 0.015), which equates to an incremental cost-effectiveness ratio (cost difference divided by QALY difference) of £167,620. Limitations: Although the measurement of outcomes was carried out by optometrists who were masked to the treatment arm, the participants were not masked. Conclusions: The evidence suggests that FLACS is not inferior to PCS in terms of vision after 3 months’ follow-up, and there were no significant differences in patient-reported health and safety outcomes after 12 months’ follow-up. In addition, the statistically significant difference in binocular corrected distance visual acuity was not clinically significant. FLACS is not cost-effective. Future work: To explore the possible differences in vision in patients without ocular co-pathology. Trial registration: Current Controlled Trials ISRCTN77602616. Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 6. See the NIHR Journals Library website for further project information. Moorfields Eye Charity (grant references GR000233 and GR000449 for the endothelial cell counter and femtosecond laser used).
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