Comparison of the actual diameter of capsulotomy and predicted diameter of capsulotomy after femtosecond laser-assisted capsulotomy

Purpose: To compare the consistency between the actual diameter of capsulotomy (ADC) and the predicted diameter of capsulotomy (PDC) in femtosecond laser-assisted cataract surgery (FLACS) and analyze the factors that influence the deviation of the diameter of capsulotomy (DDC) between the actual and predicted. Setting: Aier Eye Hospital of Wuhan University, China. Design: Retrospective observational case series. Methods: Patients who underwent FLACS from March 2020 to March 2021 were reviewed. The ADC in FLACS was measured and compared with the PDC. The effects of age, sex, and biometrics on DDC were analyzed. Results: 412 eyes of 336 patients were included. The mean age was 53.0 +/- 0.91 years (range 3 to 91 years). When the PDC was set to 4.50 mm, the results showed that the ADC was 5.21 +/- 0.21 mm with a significant difference between them (P <.05). However, when the PDC was set to 5.2 mm, the ADC was 5.10 +/- 0.38 mm without a significant difference between them (P >.05). No correlation (P >.05) was found between the DDC and the axial length, the DDC and the anterior chamber depth (ACD), and the DDC and the mean keratometry (Km), but a negative correlation was found between the DDC and the lens thickness (LT) (r = -0.21; P <.05) and the DDC with age (r = -0.70; P <.05). Using curvilinear regression analysis, a development of an age-depending correction formula was predicted: ADC = PDC + 1.23 - 0.30 ln (x) (x = age >= 3) (R-2 = 0.65; F = 752.39; P = .00). Conclusions: The consistency of the ADC and PDC was influenced by age and LT. For patients aged 40 years or younger, the younger the patient, the wider the DDC; for patients older than 40 years, the DDC was small. The thicker the LT, the smaller the DDC. Copyright (c) 2022 Published by Wolters Kluwer on behalf of ASCRS and ESCRS