The MIRO® CORNEA UR is a new keratoprosthesis made of a single piece of flexible, hydrophobic acrylic polymer. The geometry is based on the original Cardona design, allowing epicorneal as well as intrastromal implantation. The haptic is coated with genetically engineered fibronectin, supporting the adherence of surrounding tissue. The flexibility of the haptic minimizes shear stress between keratoprosthesis and ocular tissue, and supports intraocular pressure monitoring in patients with a high incidence of glaucoma.
Material and methods
The MIRO® CORNEA UR was implanted into one eye each of four corneally blind patients suffering from autoimmune disease or severe burns. The haptic was implanted in a pocket between the ocular globe and beforehand transplanted autologous buccal mucosa, and additionally secured by a skirt of donor sclera or a collagen membrane.
In three out of four eyes, the surrounding tissue firmly adhered to the haptic and penetrated the holes in the haptic. Throughout the follow-up period of 20–52 months, the haptics were firmly integrated into the surrounding tissue without signs of inflammation. Postoperative medication included antibiotics and cortisone drops. The eyes remained stable, well pressurized and free from infection. Neither tissue melting nor ingrowth of epithelial cells along the tissue–keratoprosthesis interface were observed.
The MIRO® CORNEA UR keratoprosthesis may be an alternative to the osteo-odonto-keratoprosthesis (OOKP) in the treatment of corneally blind patients with autoimmune disease or severe burns. In the future, indications may include deep corneal vascularization for example after ocular infection.