The purpose of this randomized clinical trial is to compare the efficacy and safety of intraoperative mitomycin C(MMC) combined with limbal conjunctival autograft(LCAG) or conjunctival autograft(CAG) for recurrent pterygium surgery. The investigators will also evaluate particular risk factors related to pterygium recurrence

Intraoperative mitomycin C after pterygium excision is widely used to prevent recurrce of recurrent pterygium. Conjunctival autograft with or without limbal tissue used to cover the bare sclera will efficiently reduce postoperative longstanding epithelial defect.

Patients with recurrent pterygium will be randomly assigned to undertake pterygium excision followed by intraoperative mitomycin C with conjunctival autograft or limbal conjunctival autograft .The patients will be followed at least 12 months. Corneal recurrence is considered as a fibrovascular ingrowth beyond the limbus with conjunctival drag in the area of previous pterygium excision.

Inclusion Criteria:

• Recurrent pterygium
• Willingness to participate in research project and to attend research time
• At least 6 months after last pterygium surgery

Exclusion Criteria:

• Pregnant,breast-feeding women or poor general health
• Patients with significant ocular or lid pathology, such as Sjogren's Syndrome ,infection, exposure keratitis,glaucoma and trauma
• Patients with allergy to mitomycin C,tobramycin or local anesthetics