Abstract
Purpose: :
To evaluate the use of the Type I Boston Keratoprosthesis in the developing world over a 36-month follow-up period in Ethiopia.
Methods: :
A longitudinal prospective study was performed through a collaboration between the Massachusetts Eye and Ear Infirmary, Boston, USA and the Menelick II Hospital, Addis Ababa, Ethiopia. Twenty pre-selected patients underwent surgery with the Type I Boston Keratoprosthesis (KPro). Patient selection criteria included hospital access, binocular blindness or monocular patients, poor penetrating keratoplasty prognosis and understanding of the procedure and care required after surgery. Lens extraction was performed in patients who were not pseudophakic or aphakic. Locally available chloramphenicol and ciprofloxacin ophthalmic solutions were used. A monthly drop with 5% povidone-iodine was recommended for broad antimicrobial prophylaxis. Patients were followed monthly to monitor visual acuity (VA), intraocular pressure (IOP), complications and medication compliance. IRB approval was obtained in both institutions.
Results: :
Twenty Ethiopian patients received a Boston KPro under local anesthesia. The preoperative diagnoses in order of frequency were: measles (6), herpetic keratitis (4), trachoma (3), repeated failed grafts (3), Mooren’s ulcer (2), Steven-Johnson’s syndrome (1), and vernal keratoconjunctivitis (1). Fresh allografts, gamma-irradiated allografts or autologous corneas were used as KPro carriers. All patients had improved visual acuity from a baseline vision of light perception or hand motion (HM). After an average follow-up time of 19±14 months (range 1 to 36 months), postoperative vision ranged from HM to 20/40 post-operatively. The complications or lost of follow-ups were: 1 bacterial endophthalmitis secondary to lack of compliance after 14 months; 1 patient died from pulmonary tuberculosis; 1 case of KPro extrusion with retinal detachment; 4 patients had pre-operative glaucoma, limiting improvement in VA; 1 patient developed temporary sterile vitritis and 1 hypotony, both cases managed successfully without loss of VA.
Conclusions: :
Our results indicate that the Boston KPro may be a viable ophthalmic device also in the developing world where corneal blindness is more frequent. KPro complications in this series, were similar and not worse compared to those in developed countries, but longer follow-up is needed. Widespread medical expertise as well as improved patient compliance is needed in the setting of a developing country.
Keywords: keratoprostheses • clinical (human) or epidemiologic studies: outcomes/complications • clinical (human) or epidemiologic studies: health care delivery/economics/manpower