Complications of Pterygium Excision

INTRODUCTION: Several theories (environmental, genetic, and various other factors) exist regarding the etiology of pterygia, a wing-shaped, fibrovascular growth of conjunctiva that advances onto the cornea. The goals of pterygium surgery are to remove the pterygium and avoid possible complications. Indications for surgery include reduced vision due to encroachment and irregular astigmatism, chronic irritation, recurrent inflammation, and ocular motility restriction. Our hypothesis was that MMC used on the bulbar conjunctiva after pterygium excision may be denuding the palpebral conjunctiva, creating two raw edges that become adherent and form a symblepharon. The purpose of our project was to determine if these complications, specifically symblepharon formation, were related to certain surgical techniques involving the use of MMC. METHODS: We performed a retrospective chart review of Parkland patients with a diagnosis of pterygium (1/1/2015-12/31/2015). We looked at 362 primary pterygia excisions from 280 patients. We recorded each patients’ sex, race, age and information regarding the pterygium such as laterality, PGY of primary surgeon, and complications. We included patients that had all their surgeries at Parkland and had at least 3 months post-op follow-up. RESULTS: A comparison of surgeries involving the use of MMC versus those that did not use MMC was statistically significant. Chi-square analysis revealed a statistical difference between surgical approach and development of a complication (p = 0.0009). A post-hoc analysis of the Chi-square revealed a statistically significant association between the use of amniotic membrane tissue and intraoperative mitomycin C with the development of post-operative complications. The post-hoc analysis also revealed that a lower number of complications were seen with the use of both amniotic membrane tissue and conjunctival autograft transplantation without MMC. DISCUSSION: This retrospective study revealed that at a major county hospital where ophthalmology trainees are the primary surgeons, the use of intraoperative MMC was generally associated with a higher rate of complications in comparison to techniques that did not involve its use. The case series revealed that symblepharons were more likely to develop if their surgical excision included the use of intraoperative MMC. The overall study findings suggest that a decrease in the use of intraoperative MMC should lead to a decrease in complications requiring additional intervention in our group of surgeons and given the difficulty in achieving resolution of symblepharon formation.