Refractive tunnel keratoplasty with synthetic implants modified by a gas-discharge plasma

Various methods of refractive interlamellar tunnel keratoplasty with synthetic implants modified by low-temperature gas-discharge plasma were used for correction of myopia and myopic astigmatism. Experiments carried out with laboratory rabbits revealed that pretreatment of hydrogel, silicon, and polymethylmethacrylate by gas-discharge plasma enhances the tolerance of corneal stroma to these synthetic materials. Clinical studies with hydrogel have shown that gas-discharge plasma treatment of traditional polymer materials is a promising method for achieving improved biocompatibility of synthetic materials to corneal stroma. Forty-four clinical tunnel keratoplasties have been conducted on humans with gas-discharge-plasma-treated hydrogel. The patients had a high degree of myopia (from 7.0 to 28.0 D) and myopic astigmatism (within the range of 5.0 to 11.0 D). Surgical methods were similar to those developed during the experimental stage of work. The patients were followed postoperatively for up to 8 years. According to these observations, circular tunnel keratoplasty with synthetic implants reduced spherical myopia up to 20.0 D. Methods for correcting of both simple and complex myopic types of astigmatism have been developed. Arc-type sectoral tunnel keratoplasty and elliptical tunnel keratoplasty allowed correction of myopic astigmatism up to 11.0 D.