Cryotherapy was performed using a Brymill CRY-AC-3 liquid nitrogen unit (Brymill Cryogenic Systems, Ellington, Connecticut). A 1.5-mm polytetrafluoroethylene (Teflon)–coated cryoprobe was used to perform a double freeze-thaw of the involved conjunctiva for 1 to 2 seconds in 2 freeze-thaw cycles. Thawing took approximately 5 to 10 seconds. Erythromycin eye ointment was placed on the eye after the procedure. Patients were seen in follow-up at 1 day, 2 weeks, 3 months, 6 months, and yearly thereafter.