Correction of myopia with the intracorneal ring

Abstract

The Implantation of intracorneal ring segments (ICRS) offers the possibility of reversible, refractive surgery for correction of lower myopia up to -5.0 D. We report our first results 1 year after implantation of ICR segments. From April 1997 to August 1998 we implanted ICRS in 48 eyes of 31 patients (12 male, 19 female) to correct myopia. The preoperative refraction (spherical equivalent) was between -1.0 and -5.0 D (astigmatism < 1.0 D). The average age was 34.0 years (range 19-48 years). ICRS implantation was performed in peribulbar anaesthesia. All operations were done by the same surgeon. The average follow-up was 10 months (ranges 1-12 months). After 6 months the deviation from the target refraction of all eyes was < 1.5 D; 26 of 27 eyes (96.3%) showed a deviation of < or = 1.0 D. Six months after surgery, 18 of 27 eyes (66.6%) showed an uncorrected visual acuity of 20/20 or better, 23 of 26 eyes (88.4%) showed 20/25 or better, and 25 of 26 eyes (96.2) 20/40 and better. Only 1 of 16 eyes showed an uncorrected visual acuity of 20/50. In all eyes, the best-corrected visual acuity was 20/20 or better. In 2 eyes an ICRS exchange and implantation of a thicker ring was necessary because the target refraction could not be achieved with the first implanted ring. In 2 eyes an ICRS reposition was done to optimize the location of the ring within the cornea. In 4 eyes we explanted the ring due to double vision (1 x) and distorted vision (3 x) caused by induced astigmatism. After explantation the preoperative refraction (+/- 0.15 D) was reached within 1 to 1.5 months. There was no regression after 6 months (n = 27) or after 1 year (n = 7). Our 1-year results of ICRS implantation show that myopia correction with the advantage of reversibility and lower complication rate is possible by this refractive surgical method. Ring exchange and explantation are possible. Earlier postoperative complaints like photophobia, unstable visual acuity or discomfort usually disappear rapidly. The decision of 95.0% of the patients to have ICRS implantation also into the second eye shows the high degree of satisfaction.