Focal pressure: a new method to encourage filtration after trabeculectomy.

One cause of failure of trabeculectomy is early closure of the sclerostomy with insufficient aqueous outflow and subsequent scarring of Tenon's capsule and conjunctiva. Ocular massage and other forms of manipulation of the scleral flap have been used in the past to enhance filtration in cases where full-thickness filtration procedures were performed, and they have been suggested for use with trabeculectomy as well. The authors propose a new method in which focal pressure is applied with an anesthetic-moistened applicator directly to the conjunctiva beside the edge of the scleral flap. This appears to be particularly indicated in trabeculectomy, and has both theoretical and practical advantages over the conventional forms of enhancing filtration in eyes having been treated with trabeculectomy. In 17 of 18 cases having trabeculectomy according to Watson's technique and in which it appeared that no filtration would develop in the postoperative period, focal pressure was successful in creating a satisfactory bleb.