Systematic Review: Effects of Pterygium and Pingueculum on the Ocular Surface and Efficacy of Surgical Excision

Purpose: This systematic review examines the specific effects of pingueculum and pterygium on the ocular surface and evaluates the efficacy of surgical excision in reversing those effects. Methods: A systematic review was performed according to the Preferred Reporting Items for the Systematic Review and Meta-Analyses statement and included 59 articles studying the effects of pterygium and pingueculum on the ocular surface as measured by tear break-up time (TBUT), Schirmer testing, tear osmolarity, Ocular Surface Disease Index (OSDI), and the effects of surgical removal on these ocular surface parameters. Results: In most studies, eyes with pterygium or pingueculum when compared with control eyes had a statistically significantly lower TBUT (average 3.72 s), lower Schirmer I without anesthesia (average 3.01 mm), lower Schirmer II (average 4.10 mm), higher tear osmolarity (average 12.33 mOsm/L), and higher OSDI (average 6.82 points). Moreover, excision of pterygium and pingueculum led to a statistically significantly higher TBUT (average 3.15 s higher at 1 mo postexcision), lower tear osmolarity (average 3.10 mOsm/L lower at 3 mo postexcision), and lower OSDI score (average 2.86 points lower 1 mo postexcision) in most of the studies. The effect of excision on Schirmer test scores was equivocal because most studies did not reach significance. Conclusions: Our data confirm the relationship between pterygium and pingueculum and abnormal tear function and symptoms of dry eye disease. Furthermore, the data suggest that tear film parameters might improve after surgical removal of pterygium or pingueculum. Future studies would be helpful in exploring the potential role of pterygium and pingueculum excision in the management of dry eye disease.