Abstract
PURPOSE: To investigate the effectiveness and safety of customized femtosecond laser-assisted corneal allogenic intrastromal ring segments (CAIRS) implantation in keratoconus patients with a history of intrastromal corneal ring segment (ICRS) explantation. SETTING: Sorocaba Eye Hospital (Hospital Oftalmológico de Sorocaba - HOS), Sorocaba, Brazil. DESIGN: Prospective case series. METHODS: We included eight keratoconus patients with stable disease and with history of ICRS explantation at least six months before the inclusion in the study. Patients were excluded if presenting any other ocular pathology. Customized CAIRS was produced and implanted using femtosecond laser LDV Z8 (Ziemer Ophthalmic Systems AG, Port, Switzerland). Patients were followed-up for six months. RESULTS: The mean reduction of the maximum, mean, and steep central keratometry was 3.03 ± 1.35 diopters (D) (p =0.01), 2.88 ± 2.51 D (p=0.02), and 2.41 ± 2.72 D (p=0.04), respectively. The mean spherical equivalent and refractive astigmatism reduced 6.28 ± 2.71 D (p =0.01), and 1.62 ± 2.83 D (p=0.16). All eyes, but one gained two or more lines of best spectacle corrected visual acuity (BSCVA).Additionally, five patients achieved a BSCVA of 20/40 or better. No intra or post-operative complications were observed. CONCLUSIONS: Customized femtosecond laser assisted CAIRS may be an effective and safe option for visual rehabilitation in keratoconus patients with previous ICRS explantation.