Офтальмохирургия (Jan 2017)
INFLUENCE OF RHBMP-2 GROWTH FACTOR IN COMPOSITION WITH COLLAGEN CARRIER ON MORPHOLOGICAL AND BIOMECHANICAL CHARACTERISTICS OF CORNEA
Abstract
In case of severe burn leukomas when keratoplasty is ineffective, the only way to restore vision is keratoprosthetics. Low biomechanical characteristics of leukoma make the surgery significantly more difficult and affect the development of complications, for their prevention and treatment the techniques strengthening cornea using autologous tissue are elaborated. However, their use has a number of difficulties, such as the selection and simulation of grafts in necessary form, weak adaptive capacity of the material and its lysis in the postoperative period. In this paper a new method is presented to improve biomechanical properties of the corneal leukoma using the implantation of collagen membrane with the growth factor of bone rhBMP-2 inthe corneal stroma. An increase of the strength characteristics of cornea 2-3 weeks after the implantation of collagen membrane with rhBMP-2 was proved experimentally.Purpose. To assess the impact of rhBMP-2 in a collagen membrane composition of the carrier on morphological and biomechanical characteristics of the cornea.Material and methods. The study was performed in 18 rabbits of the chinchilla breed. For a preparation of the implants (collagen membranes) we used a sterile 2% solution of the purified native rat collagen of the type I («IMTEK»), to which a sterile solution of rhBMP-2 (produced by the N.F. Gamaleya Center of Epidemiology and Microbiology) was added. The obtained collagen membrane was implanted into the intrastromal «from limbus to limbus» corneal pocket. The experimental period was 90 days. Corneal samples were investigated for morphology and biomechanics.Results. In the postoperative period an intense angiogenesis was observed with a moderate inflammatory reaction, which subsided on the 8th day. Histological examination revealed a graft retention followed by its replacement by young connective tissue. A study of the biomechanical properties showed a significant increase in the strength characteristics of the cornea i n the site of implant ation.Conclusions. The feasibility of morphological and biomechanical properties changes of the corneal tissue under the action of growth factor rhBMP-2 is proved. This is a promising direction for leukoma strengthening at various stages of keratoprosthetics and requires a further study.