Macular Choroidal Thickness in Keratoconus: Systematic Review and Meta-Analysis of Current Evidence

Background/Objectives: This study aimed to investigate changes and synthesize the existing evidence in macular choroidal thickness in patients with keratoconus (KC) compared to healthy controls, utilizing optical coherence tomography (OCT). Methods: PubMed and Scopus databases were systematically searched for published articles comparing choroidal thickness between patients with KC and healthy controls. The Mean Difference (MD) with 95% confidence interval (CI) was computed to compare continuous variables. Our study was registered with PROSPERO with registration ID: CRD42024605227. Revman 5.4 was used for the analysis. Results 10 studies were included in the analysis. Subfoveal choroidal thickness was increased in patients with KC compared to controls. (MD = 43.94, 95% CI = 17.36-70.51, p = 0.001, I² = 95%). Leave-one-out sensitivity analysis confirmed this finding. Conclusions: Our meta-analysis demonstrated that eyes with keratoconus have significantly increased macular choroidal thickness compared to controls. These findings highlight the need for longitudinal studies stratified by disease severity to clarify the role of choroidal changes in keratoconus progression.