Comparison of morphologic features of clear corneal incisions created with a femtosecond laser or a keratome

PurposeTo compare the morphology of clear corneal incisions (CCIs) created with a femtosecond laser (Catalys) or a keratome (2.65 mm steel) during phacoemulsification using anterior segment optical coherence tomography (AS-OCT) and analyze the intended versus the achieved morphologic characteristics of femtosecond laser–generated CCIs.SettingNorthwestern University Feinberg School of Medicine, Chicago, Illinois, USA.DesignComparative case series.MethodsEyes with femtosecond CCIs and age-matched eyes with the keratome CCIs underwent AS-OCT of the incisions 1 month after phacoemulsification. ImageJ software was used to evaluate AS-OCT images for CCI length, endothelial gaping, endothelial misalignment, and Descemet membrane detachment.ResultsIn the femtosecond group (20 eyes) and keratome group (16 eyes), the mean values were CCI length, 1.99 mm ± 0.07 (SEM) versus 2.04 ± 0.23 mm (P = .39); endothelial gaping, 0.14 ± 0.03 mm versus 0.19 ± 0.09 mm (P = .03); endothelial misalignment, 0.04 ± 0.03 mm versus 0.08 ± 0.06 mm (P = .022). No eye in the femtosecond group and 3 eyes in the keratome group had a Descemet membrane detachment (P = .04). Six femtosecond eyes and 11 keratome eyes had posterior wound retraction (P = .02). The mean CCI length was 94.9% of the intended 2.1 mm, the posterior plane depth was 93.3% of the intended 70%, and the posterior side-cut angle was 91.7% of the intended 45 degrees.ConclusionFemtosecond laser–generated CCIs had significantly lower endothelial gaping, endothelial misalignment, Descemet membrane detachment, and posterior wound retraction than keratome-created CCIs and were within 10% of the intended length, depth, and angle measurements.Financial DisclosureNeither author has a financial or proprietary interest in any material or method mentioned.