Surgical Technique for Excisional Bleb Revision Using a Rotational Conjunctival Flap for a Large Conjunctival Defect
A 68-year-old white male who had undergone a limbus-based trabeculectomy with an anti-fibrotic 12 years prior in the left eye presented to our institution complaining of persistent, disabling bleb dysesthesia despite frequent lubrication. He had also previously experienced intermittent bleb leaks. Examination revealed an avascular bleb superonasally [], with a well-controlled intraocular pressure (IOP) in the mid-to upper single digits. He elected to undergo bleb revision to alleviate pain.\nAnesthesia was achieved via retrobulbar block. The Vannas scissors were used to make a conjunctival incision demarcating the bleb. Subconjunctival preservative-free lidocaine was infused on a cannula to aid tissue dissection. The Vannas scissors were then used to excise the bleb, which measured 3 mm in its largest anteroposterior dimension. Hemostasis was achieved with wet-field eraser-tip cautery. Minimal leakage of the aqueous through the old scleral flap with well-maintained anterior chamber was noted, obviating the need to add tectonic support. A decision was made to close the conjunctival defect alone.\nDue to the previous conjunctival incision for a limbus-based trabeculectomy, the remaining conjunctiva retracted, leaving a large conjunctival defect measuring 8 mm by 8 mm []. Blunt dissection of the surrounding conjunctiva was performed using a Westcott scissors but still did not allow for direct wound closure. An alternative surgical technique, a rotational conjunctival flap, was then employed. In brief, the limbal side of the large conjunctival defect was measured by a caliper distance between points A and B, ). An equal-sized limbal peritomy was created (distance between points B and C = distance between points A and B, ). demonstrates intraoperative conjunctival peritomy and dissection. A relaxing incision (distance between points C and D) was created to facilitate the extension of the conjunctival flap for the closure. The prepared conjunctival flap was then rotated to cover the large defect []. demonstrates the resultant closure. The proximal edge of the flap (point A) was sutured to the nasal aspect of the conjunctiva remaining after excision of the bleb (point B) and the resulting linear tangential defect closed in a running fashion using 9-0 polyglactin. The flap was secured at the 12 o’clock limbus using 9-0 polyglactin, and the temporal linear defect was also sutured in a running fashion. Two horizontal mattress sutures of 9-0 polyglactin were placed through the conjunctiva at the limbus to prevent corneal migration of the conjunctival edge. The wounds were watertight at the end of the case.\nOn post-operative day 1, the patient demonstrated a small thick-walled bleb with IOP of 12 mm Hg. He reported improvement in dysesthesia. He was treated with topical prednisolone acetate and gatifloxacin. One week post-operatively, the patient had a formed bleb with IOP of 10 mm Hg, with a small slow leak along the nasal running closure. A bandage contact lens was placed. By 2 weeks post-operatively, the leak had resolved. IOP measured 17 mm Hg. During the 3rd post-operative week, a large bleb was observed. IOP measured 24 mm Hg and decreased to 16 mm Hg with massage. Brimonidine was added, and the patient was instructed to perform digital massage. One month post-operatively, IOP measured 22 mm Hg, decreasing to 15 mm Hg with massage. A subconjunctival injection of 5-fluorouracil (50 mg/ml) was given. Approximately 2 weeks later, a large bleb was observed, and IOP measured 15 mm Hg and 10 mm Hg after massage. A second subconjunctival 5-fluorouracil injection was given. At 2 months post-operatively, a large bleb was present, with IOP measuring 16 mm Hg and 9 mm Hg after massage. Timolol 0.5% once daily was added. Seven months post-operatively, the patient demonstrates a large thick-walled bleb, and IOP measures 10 mmHg []. He has had resolution of dysesthesia.