New 355-Degree Intracorneal Ring Segment for Management of Keratoconus: 1-Year Follow-up
Narrative Responses:
Purpose
To assess the visual, refractive and corneal aberrometric outcomes after the implantation of 355 D intracorneal ring segment (ICRS) in keratoconus cases, 1-year follow-up.
Methods
Twnety-five eyes of 20 keratoconus patients have been treated by a 355 ICRS. Corneal tunnels of 6 mm in diameter at 70% corneal depth using Femtosecond laser, 16 patients were male and 4 were female. Age of the patients ranged from 20 years to 42 years (mean 26 years). Eight eyes suffered from mild (average central K-reading (ACK) < 48 diopters (D)), nine eyes from moderate (48 D < ACK < 52 D) and eight eyes from advanced (ACK > 52 D) keratoconus. Main criteria for success was patient satisfaction and uncorrected distance visual acuity (UDVA). Postoperative 1-year follow-up
Results
Three patients (3 eyes) were not satisfied after final examination. One of these patient had an extremely advanced keratoconus (ACK preop 68D) who finaly received karatoplasty. After initial implantation the average improvement in UDVA was 8.4 lines. Three eyes out of the 25 eyes treated (12%) received a postoperative optimization procedure either by exchanging the implant for one with another thickness or by removal and reimplantation 2 months later. After optimization the average improvement in UDVA in the entire group (25 eyes) was 10.5 lines. No intraoperative complications were seen.
Conclusion
The presented 355 degree ICRS has refractive myopic correction through corneal re-modeling, may reduce vertical coma Z (3, -1), and RMS value of HOAs aberrations in eyes with central keratoconus, providing an improvement of UDVA and CDVA values.