Between 1973 and 1999, 203 patients (121 men and 82 women, 224 eyes) with various corneal diseases not treatable by penetrating keratoplasty underwent OOKP surgery. Of the original cohort, 181 patients (98 men and 83 women) who underwent surgery performed according to a standardized procedure were included in the current study. In the remaining 43 eyes, the surgical procedure had some nonstandard steps owing to individual anatomical conditions. For instance, in most of these cases, autologous oral mucosa was not available for implant and was replaced by autologous skin or mucous tissue from different anatomical districts (eg, vaginal mucosa). For these reasons, these 43 eyes were not included in the present study, although they underwent regular follow-up examination. Their results will be presented in a separate report. At the time of surgery, patients’ age ranged between 20 and 83 years (mean [SD], 54.3  years). All patients underwent full general and ophthalmic examination before surgery, including, whenever possible, intraocular pressure (IOP) estimated by a MacKay-Marg electronic tonometer,17 ophthalmic echography (to assess the anatomical integrity of the posterior segment and the status of the anterior segment), and visual evoked potentials to flash stimulation. Patients were enrolled in the study if they met the following inclusion criteria: preoperative visual acuity of 0.3 or less in both eyes or in the eye eligible for surgery, with an acuity of 0.1 or less in the fellow noneligible eye; no clinical signs of phthisis bulbi; no evidence of retinal detachment; and an IOP lower than 21 mm Hg, with or without hypotensive treatment. The patients eligible for surgery had been referred to one of us (Giancarlo Falcinelli) from other ophthalmic departments (in Italy, n = 168; Western Europe, n = 10; South America, n = 3) and clinically followed up by us (Giovanni Falcinelli), M.T., and P.C.). Final selection was made by one of us (Giancarlo Falcinelli), who was experienced in corneal diseases and anterior segment surgery. In all patients included in the study, corneal disease was not considered treatable by standard corneal transplantation, mainly because of severe and diffuse corneal neovascularization associated with abnormalities of the ocular surface, eyelids, and bulbar or tarsal conjunctiva. In 54 (30%) of 181 patients, 1 or more corneal transplantation procedures had been performed with unfavorable results. Preoperative diagnoses, together with demographic data of patients, are reported in Table 1. A more detailed description of clinical diagnoses for each group is as follows. Dry eye syndrome was caused by ocular pemphigoid in 39 patients, by Sjögren syndrome in 11 patients, by Lyell syndrome or toxic epidermal necrolysis in 6 patients,18 by trachomatous chronic conjunctivitis in 8 patients, by Stevens-Johnson syndrome or erythema multiforme in 4 patients, and graft-vs-host disease and congenital lid coloboma in 1 patient each. Corneal burns were induced by accidental exposure to alkali and acids in 33 and 35 patients, respectively. The advanced stage of bullous keratopathy was present in 15 eyes, with fibrosis and corneal neovascularization. Sequelae of infective keratitis were present in 13 eyes with severe corneal opacities and marked superficial and deep neovascularization. Bullous keratopathy with fibrosis and (corneal) neovascularization (15 eyes) was present in patients with repeated antiglaucoma surgeries (7 cases with congenital glaucoma). Figure 1 shows the preoperative anterior segment photographs taken from 2 patients with dry eye due to pemphigoid and chemical burn. In most patients, the disease causes serious complications at the level of the adnexa (symblepharon of varying severity, traumatic lid coloboma), anterior segment (corneal perforation or descemetocele, corneal thinning, anterior synechiae or absent anterior chamber, cataract), or posterior segment (vitreous hemorrhages, retinal detachment). None of these complications represented a criterion for exclusion from the present study. All complications were treated before OOKP surgery by surgical and/or medical treatment. Types of treatments performed for each complication are reported in Table 2. Preoperative glaucoma was present in 66 (36.5%) of 181 eyes. In all glaucomatous eyes, the disease was surgically (cyclodiastasis, a modified cyclodialysis procedure,19 or drainage valve) or pharmacologically treated (at the institution where surgery was performed or elsewhere) before OOKP surgery. In 24 glaucomatous eyes, additional glaucoma surgery was performed after OOKP surgery. Preoperative visual acuity of patients ranged from light perception only to 0.3. Light perception only was found preoperatively in 106 (58.6%) and hand motions in 47 (26%) of 181 eyes. Of the remaining 28 eyes, 25 had an acuity between counting fingers and 0.08 while in 3 eyes acuity ranged from 0.1 to 0.3. Disease duration, defined as the number of years in which corneal disease had effectively reduced visual acuity to the preoperative value, was mean (SD) 7.3 (8.9) years (range, 1-59 years). Informed consent was obtained from each patient after the aims and procedures of the study were fully explained. The study followed the tenets of the Declaration of Helsinki, and institutional review board approval was obtained.