One year results of european multicenter study of intrastromal corneal ring segments

Abstract
To assess intraoperative and postoperative complications, visual symptoms, and patient satisfaction after implantation of intrastromal corneal ring segments (ICRS®, KeraVision, Inc.) for the correction of myopia and to demonstrate the reversibility and adjustability of refractive corrections with this method. Twelve European investigational sites. Patients with myopia of –1.0 to –6.0 diopters (D) were assigned to receive 1 of 5 ICRS thicknesses (0.25, 0.30, 0.35, 0.40, or 0.45 mm). Complications and visual symptoms were noted, and patient satisfaction was assessed at each postoperative visit (1 and 7 days and 1, 2, 3, 6, and 12 months). Refractive data were assessed after removal or exchange of the ICRS. Of 163 eyes of 110 patients enrolled, 159 eyes of 107 patients were implanted with an ICRS (52 patients had bilateral implantation). Intraoperative complications occurred in 2% of eyes (4/163 eyes in 3 patients) that were withdrawn from the study: 3 eyes had anterior surface perforations and 1 had a posterior microperforation into the anterior chamber. Most patients had no visual symptoms at 12 months; symptoms usually occurred rarely or sometimes and were mild in severity. At 12 months, good or excellent patient satisfaction was reported for 94% of eyes. Twelve ICRSs (8%) were removed, mainly because of undercorrection and induced astigmatism, and 2 were exchanged. All eyes were within ±1.00 D of the preoperative manifest refraction spherical equivalent. The ICRS was safe for correction of low to moderate myopia. Severe postoperative visual symptoms were rare, and patient satisfaction was high. The refractive correction was largely reversible.