Induced Astigmatism and Concomitant High Myopia Correction with Femtosecond Laser-assisted Intrastromal MyoRing Implantation

Abstract

Purpose. Analysis of the results of astigmatism correction after penetrating keratoplasty and concomitant high myopia using the MyoRing ring implantation, clinical case as an example. Material and methods. Patient G., 51 years old, underwent surgery to correct astigmatism and concomitant high myopia. MyoRing was implanted in the right eye within corneal transplant limits using femtosecond laser-assisted intrastromal MyoRing implantation. Before the surgery uncorrected visual acuity at the operated eye was 0.01; corrected visual acuity 0.06; spherical component of refraction was (–)6.0 D, cylindrical component was (–)8.0 D. Mean keratometry in the right eye was 43.96 D. Corneal hysteresis was 6.5 mm Hg, corneal resistance factor was 5.5 mm Hg, cornea thickness in center was 529 mkm. The patient was followed up for one year. Results. In 12 months after the surgery visual acuity of the right eye without correction was 0.7 and 0.8 with correction. Spherical component was (–)1.0 D, cylindrical component was (–)2.0 D. Mean keratometry in the right eye was 35.10 D. Corneal hysteresis was 7.2 mm Hg, corneal resistance factor was 6.3 mm Hg, cornea thickness in center was 533 mkm. The patient was satisfied with the result of operation. Conclusion. Femtosecond laser-assisted intrastromal MyoRing implantation for correction induced astigmatism after penetrating keratoplasty and concomitant high myopia is efficient, safe and provides strengthening of biomechanical properties of the cornea besides refractive and visual effect. Key words: postkeratoplastic astigmatism, high myopia, MyoRing, femtosecond laser