ABSTRACT
BACKGROUND AND OBJECTIVE: To evaluate the efficacy and safety of the Boston Type I keratoprosthesis. PATIENTS AND METHODS: Twelve patients who underwent surgery with implantation of the Boston Type I keratoprosthesis were monitored. The following parameters were considered: diagnosis, comorbidity, previous surgery, preoperative and postoperative visual acuity, complications, and keratoprosthetic retention. RESULTS: The follow-up period ranged from 6 to 42 months (mean: 23 months). The mean number of previous keratoplasties was 2.0. The percentage of patients whose best-corrected visual acuity improved was 83.3%, and 16.7% maintained their previous vision. No patient had preoperative visual acuity better than 0.05. Patients with glaucoma comorbidity had the most limited final postoperative vision. Four eyes presented limited corneal melt. In another two eyes, corneal stromal bleeding led to a vitreous hemorrhage that was completely resolved after some weeks. No endophthalmitis or extrusion of the device occurred. CONCLUSION: The Boston Type I keratoprosthesis has a visual rehabilitation potential in cases of complicated corneal blindness, where the prognosis of a conventional keratoplasty is considered poor. Anatomical retention may be favorable in the medium term.
Subject(s)
Artificial Organs , Cornea , Corneal Diseases/surgery , Polymethyl Methacrylate , Prostheses and Implants , Prosthesis Implantation , Adult , Aged , Aged, 80 and over , Artificial Organs/standards , Corneal Transplantation/instrumentation , Corneal Transplantation/methods , Female , Follow-Up Studies , Graft Survival , Humans , Male , Middle Aged , Postoperative Complications , Prospective Studies , Prostheses and Implants/adverse effects , Prostheses and Implants/standards , Prosthesis Implantation/instrumentation , Visual AcuityABSTRACT
PURPOSE: To evaluate the long-term effectiveness of nasolacrimal stents for the treatment of obstructive epiphora, and the complications related to the procedure. METHODS: This study is a non-randomized prospective clinical trial. Eighty-five patients underwent fluoroscopally-guided placement of polyurethane stent in 86 lacrimal systems for the treatment of severe idiopathic obstructive epiphora. The sites of obstruction were: sac-duct junction (n = 65), sac (n = 10), and nasolacrimal duct (n = 11). The procedure was performed in an outpatient basis under local anesthesia. Patients were followed for a mean of 24 months (1-84) with clinical examinations and/or dacryocystography. Clinical success was defined as symptoms resolution or improvement, and the patency of the lacrimal system to irrigation. RESULTS: Stent placement was technically successful in 76 (88.4%) eyes. Technical failures (11.6%) were caused by inability to pass the guide-wire through the lacrimal system. Immediate complications occurred in 19 (22%) eyes, were mild and included: self-limited epistaxis (7), mild palpebral hematoma (7), moderate pain (3), lacrimal puncta bleeding (1), palpebral emphysema (1), and false passage (1). Of the 76 inserted stents, 33 (43.4%) became occluded, and 43 (56.6%) remained patent after a mean of 24 months. Mean duration of stent patency was 38 months. Clinical success was achieved in 40 (52.6%) of the successfully implanted stents. CONCLUSIONS: The procedure is well tolerated and can be performed on an outpatient basis. Patency decreases with follow-up, and, in the long-term, the success rate is inferior to that achieved by external dacryocystorhynostomy. However, it many be considered as a valid alternative to surgery in selected patients.
