Abstract
PURPOSE: To evaluate long-term follow-up data on implantation of a full-ring intra-corneal implant (MyoRing) for management of keratoconus. METHODS: A total of 40 keratoconic eyes of 37 consecutive patients who had undergone MyoRing implantation using the Pocket Maker microkeratome (Dioptex, GmbH, Linz, Austria) and completed 3 years of follow-up appointments were included in this retrospective study. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refraction and keratometry (K) readings were measured and evaluated preoperatively, and 3 years, postoperatively. RESULTS: No intraoperative complications were observed in this case series. Three years postoperatively, there was a significant improvement in UDVA, CDVA, K readings, spherical equivalent (SE), and manifest sphere and cylinder (P < 0.05 for all comparisons). UDVA was significantly improved from 1.14 ± 0.27 to 0.30 ± 0.21 LogMAR (P = 0.001), CDVA was also improved from 0.52 ± 0.23 to 0.18 ± 0.12 LogMAR (P = 0.001), SE was decreased by 4.35 diopters (D) and average keratometric values were reduced by 2.34 D (P = 0.001). Overall, 81% of subjects were moderately to highly satisfied 3 years after surgery and 64.90% agreed to have the fellow eye implanted with MyoRing. CONCLUSION: MyoRing implantation using the Pocket Maker microkeratome was found to be a minimally invasive procedure for improving visual acuity and refraction in the majority of the patients with keratoconus.