Revision of thin-walled cystic bleb by transposing conjunctival flap technique
Objective: To investigate the clinical effect of transposing conjunctival flap technique on thin-walled cystic blebs after trabeculectomy for treatment of glaucoma.
Methods: Fifty-two eyes of 46 patients with thin-walled cytic blebs were underwent this modified operation. The procedure involved incising the conjunctiva surrounding the preserved bleb, then the conjunctiva-Tenon's fascia flap superior or temporal to the cystic bleb was relaxed and mobilized to cover the bleb surface after topical cryopexy. The anterior margin of the flap was sutured onto the peripheral cornea. In order to relax the conjunctival flap sufficiently, an incision was made close to the superior fornix above the flap and parallel to limbus to decrease the tension.
Results: In the follow-up of 6 months-4 years, the mean intraocular pressure (IOP) of 52 eyes increased to postoperative (12.98 plus minus 5.70) mm Hg from preoperative (4.25 plus minus 1.33) mm Hg (1 mm Hg = 0.133 kPa) (t = 3.26, P < 0.01), 51 eyes maintained the filtering function. Post-operatively, the bleb leakage in 20 eyes and macular edema in 6 eyes disappeared. Local antiglaucoma medication was required in one eye, because the bleb disappeared with increasing IOP. The post-operative visual acuities were elevated in comparison with that before the operation (chi(2) = 16.65, P < 0.01).
Conclusions: The transposing conjunctival flap technique is an effective surgery for the repair of thin-walled cystic bleb whose complications, such as hypotony, maculopathy, bleb leakage or endophthalmitis can be cured or prevented.