Corneal Endothelial Polymegathism and Pleomorphism Induced by Daily-Wear Soft Contact Lenses.

Background: Corneal endothelium is responsible for maintaining cornea transparency by pumping fluid out of the stroma to prevent the development of corneal edema which leads to blurring of vision.

Purpose: The study aims to investigate the corneal endothelial cell density and morphology in young myopic patients wearing disposable soft contact lenses (SLC) using a non-contact specular biomicroscope.

Methods: A cross-sectional comparative study was conducted at Qassim University's optometry clinics from February to July 2024 in 100 healthy myopic patients, including 100 eyes wearing disposable soft contact lenses and 100 eyes wearing spectacle correction as control group. Clinical examinations included assessment of refractive error via autorefractometer and visual acuity via projector vision chart. Non-contact specular biomicroscope imaging was used to gather data on corneal endothelial cell density and morphology. Data were analyzed using SPSS v 25 (IBM Corp., Armonk, NY, USA).

Results: A total of 100 healthy myopic patients (200 eyes) participated in this study. Sixty-five (65%) were females and 35 (35%) were males. One hundred eyes wore SCL and 100 eyes were control group. The mean age was 22.14±1.92 years. The mean central corneal thickness (CCT) was 559.54±29.72.91 µm in the SCL group and 539.64±37.55 µm in the control group (p<0.001). The mean endothelial cell density (ECD) was 2628.03±238.66 cells/mm and 2589.29±254.49 cells/mm in SCL wearers and control group respectively (p=0.285). The mean coefficient variance (CV) was 35.44±6.07% in SCL wearers and 35.57±4.39% in non-wearers (p=0.023). The mean hexagonality (HEX) was 44.75±10.03% in SCL wearers and 44.83±8.40% in the control group (p=0.045). There was significant difference in cell number (p=0.018), polymegathism (p=0.002) and pleomorphism (p=0.002) between males and females in SCL wearers. Duration of SCL wear has negative correlation with ECD (r=-0.245; p=0.014) and polymegathism (-0.229; p=0.022). There was significant difference in CCT (p=0.005) and CV (p=0.027) in different types of SCL.

Conclusion: Wearing disposable soft contact lenses induces significant morphological changes in the corneal endothelium. It increases central corneal thickness and decreases degree of polymegathism and pleomorphism. The longer an individual wears contact lenses, the higher the likelihood decrease in endothelial cell density and polymegathism.