Corneal cellular characteristics according to the degree of keratoconus by confocal microscopy

Objective: To analyze the relationship between the degree of keratoconus and corneal cellular changes based on information obtained through confocal microscopy.Methods: This study is observational, analytical, and prospective, where the sample included 120 eyes from patients diagnosed with keratoconus who were treated in the Cornea and Refractive Surgery Department at Fundación Hospital Nuestra Señora de la Luz, I.A.P., between April and August of 2024.Results: The mean age of all subjects was 24.6 ± 6.93 years (range 14-46 years).In the epithelium, a progressive decrease in cell density was observed, from grade I (4,710.1 cells/mm²) to grade IV (2,795.2cells/mm²), together with an increase in intercellular space and a higher frequency of elongated morphology in advanced grades.These changes were statistically significant (p < 0.05).The whorl-like pattern was observed only in grades II and III, while no significant relationship was found between hyperreflective epithelial deposits and the grade of the disease.In the stroma, a significant decrease in keratocyte density was observed.Features e.g., microlacunae, alternating bands, and the honeycomb pattern were more frequent in advanced grades, as well as changes in keratocyte morphology and reflectivity (p < 0.05).In the endothelium, cell density decreased notably in advanced grades, while pleomorphism and polymegathism were present in most cases, regardless of grade.Additionally, Bowman's membrane showed ruptures and keratocyte presence in moderate and advanced grades, reflecting a degenerative process associated with keratoconus progression.Conclusions: These findings confirm constant cell turnover, morphological and structural changes in corneal tissue regarding contact lens use, inflammatory processes, and tissue thinning.