Primary pterygium is not associated with corneal endothelial cell decrease in a rural Chinese population

Abstract Purpose: To investigate corneal endothelial cell density (ECD) in eyes with primary pterygium. Methods: We first conducted a retrospective study to compare the ECD between 1670 eyes with primary pterygium and 4060 eyes without pterygium. Then we designed a prospective study to confirm the findings of our retrospective study in 95 patients with unilateral primary pterygium. Results: In the retrospective study, the mean ECD in eyes with primary pterygium (2453±306 cells/mm2) was significantly lower than those in eyes without pterygium (2529±313 cells/mm2, P<0.0001). However, the difference was not as high as previously reported (76 cells/mm2, 3.1%). In the prospective study, there was no significant difference in mean ECD in eyes with unilateral primary pterygium (2480±263 cells/mm2) and the contralateral eyes with no pterygium (2527±277 cells/mm2, P=0.20). There was also no significant difference in hexagonality (P=0.10) or coefficient of variation of size (P=0.15) of corneal endothelial cells between eyes with pterygium and the contralateral eyes with no pterygium. Conclusion: Primary pterygium may not be associated with a decrease in ECD in our study population of rural Chinese patients.