Closure of leaking filtering blebs with cyanoacrylate tissue adhesive. Five leaking filtering blebs, occurring between 10 months and 21 years after trabeculectomy, were closed with cyanoacrylate tissue adhesive. Filtering bleb integrity was preserved in four cases, so that additional microsurgery was avoided. The only problem associated with use of tissue adhesive was the development of corneal abrasions in three cases. Although it is an accepted treatment for these conjunctival fistulas, only nine previous cases have been reported to our knowledge. We strongly recommend the use of tissue adhesive as a presurgical treatment in the management of leaking filtering blebs which present as a late postoperative complication of glaucoma surgery. 