Role of concanavalin A lectin in recognition of pterygium remnant after surgical excision: Preliminary results of a prospective study

BACKGROUND: Pterygium is one of the most common conjunctival diseases among ophthalmic pathologies. The frequency of recurrences is high, either after surgical treatment or after treatment combined with mitomycin C or beta-radiation therapy. AIMS: The purpose of this study was to determine whether concanavalin A (ConA) lectin bound to the pterygial surface can be used to detect recurrence or remnants of pterygium after surgical excision. MATERIALS AND METHODS: This was a prospective study on 20 patients with pterygium, divided in five stages, pre-surgery, early post-surgery (24h), late post-surgery (seven days), very late post-surgery (four weeks) and two months after the procedure. A drop of fluorescein-marked Con A (35 µg/mL) was instilled in the lower conjunctival eyelid sac and the eye was exposed to the light of a Wood′s lamp for an average of five seconds. RESULTS: Out of the 20 patients, eight patients were found to have fluorescent stretch marks over the scar corresponding to residual pterygial tissue at four weeks; two months after the procedure of re-surgery we observed no fluorescent remnants. All residual pterygia were confirmed through histochemistry studies. CONCLUSION: It was possible to detect remnants of pterygium in postoperative patients and recurrences in early pre-clinical stages through the visualization of fluorescent ConA bound to the pterygial surface.