Vitrectomy for pars plana placement of a glaucoma seton

Trabeculectomy, even with supplemental antifibrosis agents, has a low success rate in controlling intraocular pressure (IOP) in certain cases; ones involving severe anterior-chamber-angle disease are particularly challenging. Ten patients with advanced, non-neovascular glaucoma underwent vitrectomy and pars plana placement of seton implants. The tube was placed through the pars plana sclerotomy in each case because severe anterior chamber angle narrowing, aphakia, or penetrating keratoplasty prevented standard placement. Previous trabeculectomy had failed to control IOP in 9 of the 10 patients. In each, the preoperative IOP was 25 mm Hg or more despite maximal medical therapy. In nine of the patients, the postoperative IOP was 19 mm Hg or less, without pressure-lowering agents. The seton appeared to be functional in all of the cases. Vision remained stable or improved in seven cases, but deteriorated in three due to graft failure, progressive traction retinal detachment, or rhegmatogenous retinal detachment (one case each). Pars plana placement of tubes for glaucoma seton implants should be considered as an alternative to anterior chamber placement in certain cases of refractory glaucoma in which the anterior chamber anatomy has been severely disrupted.