Ring tunnel keratoplasty in high and extreme myopia correction

A surgical method for correction of high and extreme myopia was developed.

The corneal optical zone is flattened by bringing strip-shaped corneal grafts into the interlamellar tunnel surrounding the corneal optical centre. Instruments and an operative technique were developed.

In 72 operations on rabbits, dependency of the refractive effect on ring diameter and transplant thickness was revealed. In the clinic, the average refractve effect of 100 consecutive standard operations was 10.1 +/- 2.0 D. The maximal refractive effect was 14.5 D. Regression of the refractive effect was 12%.

Ring tunnel keratoplasty was shown to be a reliable method of optical correction.