The relationship between refractive error and central corneal thickness in patients seen at Federal Teaching Hospital, Owerri, Imo State

Abstract

Background: Refractive error and central corneal thickness are factors that can affect vision relatedly. Refractive errors, including  myopia, hyperopia and astigmatism are common visual anomalies that affect millions worldwide. Central corneal thickness influences the eye's biomechanical stability and susceptibility to various ocular conditions.

Objective: To determine the relationship between refractive error and central corneal thickness (CCT) in participants seen at Federal Teaching Hospital, Owerri.

Methods: This is an analytical, cross-sectional study of 175 non-glaucomatous patients. A purposive sampling method was used to recruit  participants. Data was analyzed using SPSS version 19.0 Statistical software

Results: The highest proportion of participants were  in the 41-50 years (20.6%)age group. The females were (66.9%) and males (33.1%). (M: F= 1.0:2.02). The mean refractive error for the right  and left eyes were -0.24DS and -0.19 DS respectively while the mean CCT for the right and left eyes were 534.30µm and 528.71µm  respectively. There was no significant difference in the refractive error between the two eyes of the participants (p=0.443), but a  significant difference in the central corneal thickness (p=0.001). There was a significant relationship between refractive errors and central  corneal thickness (p=0.008). For every unit rise in refractive error in the positive direction, the central corneal thickness increased by  4.073µm, while controlling age meaning that the central corneal thickness is thicker in hyperopes than in myopes.

Conclusion and  Recommendation: Myopes had thin central corneal thickness while Hyperopes had thicker central cornea. Myopes should have  pachymetric evaluation considering that their thin cornea may result in underestimation of the intraocular pressure