2Health Sciences University, Kayseri Faculty of Medicine, Department of Ophthalmology, Kayseri, Türkiye DOI : 10.37845/ret.vit.2026.35.29 Purpose: To investigate the changes of subfoveal choroidal thickness (SFCT) and subfoveal and submacular choroidal vascularity index (CVI) in eyes underwent photorefractive keratectomy (PRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) surgery.
\r\nMethods: In this single-center, retrospective cross-sectional study, 32 eyes from 32 patients in FS-LASIK and 38 eyes from 38 patients in PRK were included. All participants were examined by enhanced depth imaging optical coherence tomography (EDI-OCT) for SFCT and subfoveal and submacular CVI measurements at pre-operatively and post-operative 1st and 7th day.
\r\nResults: The mean spherical equivalent was higher in FS-LASIK group than PRK group in the pre-operative period (p < 0.001), but similar in both groups in the post-operative period (p > 0.05, for both). The mean SFCT and subfoveal CVI statistically significant increase in both groups on the 1st post-operative day compared to the pre-operative period (p < 0.05, for both). There was no significant difference in submacular CVI in both groups between pre-operative and post-operative period (p > 0.05, for both).
\r\nConclusion: We found an increase in SFCT and subfoveal CVI in both groups on the first post-operative day. This may be due to increased inflammatory response and vascular permeability after surgery. Additionally, in the FS-LASIK group, mechanical stretching of the choroid during the vacuum phase and the temporary increase in IOP may have contributed to this increase.
Keywords : Femtosecond laser-assisted laser in situ keratomileusis; Photorefractive keratectomy; Spectral-domain optical coherence tomography; Enhanced depth imaging; Choroidal thickness; Choroidal vascularity index