The association between primary pterygium and corneal endothelial cell density

BACKGROUND: To investigate corneal endothelial cell density in eyes with primary pterygium. METHODS: A retrospective study was conducted to compare endothelial cell density between 1,565 patients with primary pterygium and 3,448 patients without pterygium. Then a prospective study was designed to confirm the findings of the retrospective study in 95 patients with unilateral primary pterygium. RESULTS: In the retrospective study, the mean endothelial cell density in eyes with primary pterygium was significantly lower (2,454 +/- 303 cells/mm(2) ) than those in eyes without pterygium (2,525 +/- 312 cells/mm(2) , p < 0.0001). However, the difference was not as high as previously reported (71 cells/mm(2) , 2.9 per cent). In the prospective study, there was no significant difference in mean endothelial cell density in eyes with unilateral primary pterygium (2,480 +/- 263 cells/mm(2) ) and the contralateral eyes with no pterygium (2,527 +/- 277 cells/mm(2) , p = 0.20). There was also no significant difference in hexagonality (p = 0.10) or co-efficient 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 endothelial cell density in our study population of rural Chinese patients.