Femtosecond Laser–Assisted Superficial Lamellar Keratectomy For Anterior Corneal Opacities
Published 2024 - 42nd Congress of the ESCRS
Reference: FP24.12 | Type: Free paper | DOI: 10.82333/xvh4-ey77
Authors: Mariana Ferreira Francisco* 1 , João Gil 2 , Esmeralda Costa 2 , Andreia Rosa 2 , Cristina Tavares 3 , Maria João Quadrado 2 , Joaquim Murta 2
1Ophthalmology,Hospitais da Universidade de Coimbra, Unidade Local de Saúde de Coimbra,Coimbra,Portugal, 2Ophthalmology,Hospitais da Universidade de Coimbra, Unidade Local de Saúde de Coimbra,Coimbra,Portugal;Clinical Academic Centre of Coimbra, Hospitais da Universidade de Coimbra, Unidade Local de Saúde de Coimbra,Coimbra,Portugal;Faculty of Medicine, University of Coimbra (FMUC),Coimbra,Portugal, 3Ophthalmology,Hospitais da Universidade de Coimbra, Unidade Local de Saúde de Coimbra,Coimbra,Portugal;Clinical Academic Centre of Coimbra, Hospitais da Universidade de Coimbra, Unidade Local de Saúde de Coimbra,Coimbra,Portugal
Purpose
Corneal opacities are a common cause of vision loss. Femtosecond laser-assisted lamellar keratectomy (FLK) is a relatively new technique that proposes the selective removal of layers of corneal tissue using femtosecond laser, leaving behind a smooth stromal bed with good optical quality. The goal of this work is to report on the visual, tomographic and refractive outcomes of patients with severe corneal opacities treated with FLK.
Setting
Ophthalmology Department, Hospitais da Universidade de Coimbra, Unidade Local de Saúde de Coimbra, Coimbra, Portugal.
Methods
Patients diagnosed with clinically significant corneal opacities, limited to the anterior stroma (under 200 μm depth) underwent surgery between May 2023 and January 2024. The depth of the corneal opacity was determined using anterior segment optical coherence tomography. FLK was performed to remove a central corneal free cap of 8.5mm in diameter at a depth of 110 to 170μm. After cap removal, the stromal bed was soaked with mitomycin C for 20 seconds, followed by copious irrigation with a balanced salt solution. The excised free cap was sent for histological analysis. Preoperative and postoperative refraction, best corrected visual acuity (BCVA), and corneal tomography results were evaluated.
Results
A total of 7 eyes from 6 patients were included. Two eyes were diagnosed with Reis-Buckler dystrophy, 2 with macular dystrophy, 2 with post-infectious and 1 with post-chemical burn scarring. Mean age was 47.42±22.69 years old. Mean flap thickness was 135.71±24.40µm. Mean BCVA (logMAR) improved from 0.53±0.16 before surgery to 0.35±0.21 at 3 months after surgery (p=0.53). All cases but 1 gained more than 1 line of BCVA. Mean spherical equivalent was not significantly changed (-0.16±2.71 to 0.88±2.66 D, p=0.34). Mean keratometry changed from 41.79±3.34 to 39.37±1.69 (p=0.23) in the flat meridian, and from 44.46±4.12 to 42.07±2.07 (p=0.50) in the steep meridian. No residual corneal opacities were noted after surgery.
Conclusions
FLK is an effective surgical option in patients with severe corneal opacities of multiple etiologies. It improves visual acuity, while maintaining refractive and keratometric stability. It can provide both therapeutic and diagnostic intervention and help to defer more invasive surgeries.