Corneal densitometry and anterior segment changes in patients undergoing maintenance hemodialysis.

PURPOSE: To evaluate corneal densitometry and anterior segment parameters in patients undergoing maintenance hemodialysis compared with healthy controls, and to assess acute changes following a single hemodialysis session. METHODS: This prospective controlled observational study included 66 eyes of 66 subjects: 30 patients undergoing maintenance hemodialysis and 36 age-matched healthy controls. Anterior segment imaging was performed using a rotating Scheimpflug camera (Pentacam HR). Corneal densitometry values were analyzed across predefined corneal layers and annular zones. In the hemodialysis group, measurements were obtained immediately before and 1 h after dialysis, enabling both between-group (controls vs pre-dialysis) and within-group (pre- vs post-dialysis) comparisons. Anterior segment and pachymetric parameters were also recorded. RESULTS: The primary outcome, total corneal densitometry in the central 0-2 mm zone, was significantly higher in patients undergoing maintenance hemodialysis than in healthy controls (16.65 ± 1.18 vs 15.92 ± 1.30 GSU; mean difference: 0.73 GSU; 95% CI: 0.12-1.34; FDR-adjusted p = 0.027). Additional increases were observed across posterior and peripheral corneal regions, with the largest mean difference observed in the total 10-12 mm zone. Following hemodialysis, densitometry increased further, most prominently in the anterior 0-2 mm zone (20.82 ± 1.51 vs 22.31 ± 1.69; FDR-adjusted p < 0.001). Additional differences were observed in anterior segment and pachymetric parameters both between groups and after dialysis. CONCLUSION: Patients undergoing maintenance hemodialysis demonstrate increased corneal light scatter compared with healthy controls, along with additional acute changes following a dialysis session. Corneal measurements should therefore be interpreted in relation to the timing of dialysis.