[Surgery for intraocular hypotony due to avascular filtering blebs]

Corneal patch graft for the repair of late-onset hypotony or filtering bleb leak after trabeculectomy: a new surgical technique

PURPOSE

Repair of leaking filtering blebs after trabeculectomy is a surgical challenge, especially when the patient presents with hypotony. Repair of the filtering bleb using only conjunctiva reconstruction often fails when deeper tissue structures do not provide sufficient outflow resistance. Here, we present a technique that uses anterior stromal lamellae left over from donor corneas used for descemet stripping automated endothelial keratoplasty procedures as patch grafts to repair the scleral tissue wound as a way to treat ocular hypotony.

MATERIALS AND METHODS

We describe a new surgical technique to reconstruct the outflow resistance of melted trabeculectomy scleral flaps and present the course of 5 cases of severe hypotony treated using this technique.

RESULTS

All 5 patients suffered from severe hypotony several years after trabeculectomy with antiproliferative agents. Multiple surgical and nonsurgical attempts to treat hypotony had failed. Lamellar corneal tissue was used as a patch graft to replace the weakened sclera near the site of the earlier trabeculectomy. This procedure successfully reversed hypotony in all cases. During the follow-up periods of at least 9 months, no recurrences of bleb leak or hypotony were observed. Intraocular pressure (IOP) remained controlled with topical IOP-lowering treatment in 4 cases. In 1 case, a glaucoma drainage implant was used to control IOP.

CONCLUSIONS

The use of lamellar corneal donor tissue to restore scleral outflow resistance is a safe and effective treatment for severe hypotony after mitomycin C-assisted trabeculectomy with or without filtering bleb leaks.