Purpose: To demonstrate the risk of developing polymegathism in PMMA contact lens users which can be suggestive of endothelial stress. Methods: Data were obtained from patients who underwent corneal specular microscopy in the last 6 years by the same examiner. Patients were separated in two groups: one of 43 PMMA contact lens users and a control group of 34 patients with a mean age similar to the study group. A contact specular microscope was used and a semiautomated analysis of endothelium mosaic was made. Results: There were 29 (67.5%) females and 14 (32.5%) males in the study group. The mean age of the study group was 37.86±9.81 and 37.08±6.59 of the control group. The mean time of the lens use was 17±7.5 years. The study group had 53.5% polymegathism and only 11.76% in the control group. The odds ratio found was 8.63 (2.33 < OR < 34.90) and the estimated and uncorrected chi-square was 14.52 with a p<0.01. Among the 23 cases with polymegathism from the study group, 6 (34.78%) had minimal stress, 10 (43.47%) had moderate stress and 7 (21.74%) had marked stress. Conclusion: A 8 times higher risk was determined for hard contact lens users to develop endothelial stress compared to the control group of the same age.
PMMA contact lenses; Corneal endothelium; Polymegathism
