Corneal trabeculectomy without conjunctival incision. Extended follow-up and histologic findings

Corneal trabeculectomy, a guarded filtration procedure without conjunctival incision but with an iridectomy, was developed in 30 eyebank and 20 rabbit eyes before being applied to humans.

Corneal trabeculectomy was performed in one eye and conventional trabeculectomy in the contralateral eyes of six rabbits. Sequential postoperative histologic examinations were performed on these eyes at various times after surgery. Corneal trabeculectomy also was performed in 20 eyes of 18 patients with glaucoma for control of their intraocular pressure (IOP).

Results of histologic examination on these rabbit eyes showed less subconjunctival inflammation and fibrosis after corneal trabeculectomy than conventional trabeculectomy. In the eight patients with glaucoma who had had their surgery at least 1 year previously, the mean IOP decreased from 31 mmHg (preoperatively) to 14 mmHg. Eighty-eight percent have IOPs less than or equal to 18 mmHg without medications or revision.

Extended follow-up shows that corneal trabeculectomy is a low-tech, relatively atraumatic filtration procedure without conjunctival incision, which produces diffuse and persistent blebs and controls IOP. Results of sequential postoperative histologic examination in rabbit eyes suggest that corneal trabeculectomy may incite less subconjunctival inflammation than conventional trabeculectomy.