Corneal ring segments implantation as a self-sufficient method for correcting ametropia in patients with keratoconus

Abstract

Objective. To evaluate the potential of corneal ring segments implantation as a selfsufficient method for correcting ametropia in patients with keratoconus of stages I and II. Material and methods. Fourteen eyes (10 patients) with keratoconus of stages I and II (according to the classification of S.B. Izmailova, 2014) were examined and treated surgically. Patients were divided into two groups depending on the stage of keratoconus. All patients underwent femtosecond laser-assisted corneal ring segments implantation. The average follow-up period was 5.7 months. Results. In group 1: the average UCVA increased from 0.31±0.21 to 0.81±0.31 (p<0.05); the BCVA increased from 0.89±0.08 to 0.94±0.10 (p>0.05); the spherical component of refraction decreased from 0.96±1.25 D to 0.08±0.20 D (p<0.05); the cylindrical component of refraction decreased from 4.25±1.73 D to 0.50±1.22 D (p<0.05). Decreased K-max level from 51.37±3.30 D to 45.28±1.21 D (p<0.05) and decreased coma value from 1.69±0.63 D to 0.62±0.40 D (p>0.05). In group 2: UCVA increased from 0.51±0.40 to 0.61±0.28 (p<0.05); BCVA increased from 0.70±0.17 to 0.81±0.26 (p> 0.05); the spherical component of refraction decreased from 4.88±2.61 D to 0.53±0.63 D (p<0.05); the cylindrical component of refraction decreased from 2.69±1.65 D to 1.41±1.02 D (p<0.05). K-max decreased from 53.35±2.41 D to 48.21±2.5 D (p<0.05) and coma decreased from 1.69±0.63 D to 0.62±0.40 D (p<0.05). Conclusions. 1. After the corneal segments implantation, both patients with keratoconus as stages I and II showed an increase in UCVA and BCVA, as well as a significant decrease in maximum keratometry and coma, which provided patients with improved quality of vision. 2. The UCVA and BCVA achieved after treatment in all cases reached a sufficiently high level to allow patients to perform their professional functions without resorting to additional surgical treatment. This characterizes this technique as independent and self-sufficient for correcting ametropia and achieving high visual acuity in patients with keratoconus of stages I and II.