Drainage tube implants in the treatment of glaucoma following penetrating keratoplasty.

A retrospective review was undertaken to compare outcomes in 26 eyes that underwent penetrating keratoplasty (PKP) and drainage tube surgery (Molteno double-plate implant or Schocket procedure). Drainage tube surgery was performed either before PKP (10 eyes), after PKP (7 eyes), or at the same time as PKP (9 eyes). Mean follow up was 22 months. The average preoperative intraocular pressure (IOP) for all of the eyes was 31 mm Hg; 96% of them achieved a final IOP of less than 18 mm Hg (average, 14 mm Hg on a mean of 0.8 medications). Graft failure occurred in 11/26 (42%). Eight of these eyes were regrafted, and six of these eight have remained clear at a mean follow up of 22 months after regrafting. The overall PKP success rate, including the eyes that underwent repeat PKP, was 81%. Visual acuity remained stable or improved in 70% of the eyes.