Indications for Temporary Keratoprosthesis, Anatomical and Visual Outcomes

Vitreoretinal surgery can be difficult or impossible in patients with corneal opacity. One solution for this problem is use of temporary keratoprosthesis (TKP). We report anatomical and visual outcomes of this combined surgery in our institution. We retrospectively reviewed charts of patients in whom a TKP was used between 2006 and 2010 with follow-up of at least six months. Several variables such as indications for surgery, pre and postoperative visual acuity (VA), postoperative intraocular pressure (IOP), graft status, retinal status and postoperative complications were evaluated. Successful surgical outcome was defined as maintenance of clear graft, anatomic reattachment of retina, and controlled IOP. A TKP was used in 58 eyes, 43 (74.1%) of them were traumatic. Posterior segment comorbidity were retinal detachment in 39 (67.2%) eyes, vitreous hemorrhage in 19 eyes (32.8%) and endophthalmitis in 13 eyes (22.4%). All patients had corneal opacity due to scar, edema or blood staining. Postoperative VA was improved in 16 eyes (27.6%) of patients, and was unchanged in 31 eyes (53.5%) and was decreased in 11 eyes (18.9%) at the final visit. Postoperative VA was statistically better than preoperative VA (P<0.001) whether patients had retinal detachment or had not. Poor visual outcome (BSCVA≤hand motion) was seen in 49 eyes (84.5%). Only 9 patients (15.5%) achieved ambulatory vision in involved eye (BSCVA≥counting finger or 20/200-20/800). Corneal grafts remained clear in 19 eyes (32.7%). 11(18.9%) eyes had successful surgical outcome. 4 eyes (12.1%) out of 33 eyes that had not become phthisic were at risk for phthisis bulbi. Our results of simultaneous vitreoretinal surgery and penetrating keratoplasty (PKP) using TKP showed that in most patients, vision did not improved and in many patients eye cosmesis was not preserved, probably because our patients had more severe retinal and optic nerve dysfunction.