Refractive and visual outcomes after Keraring intrastromal corneal ring segment implantation for keratoconus assisted by femtosecond laser at 6 months follow-up

Abstract

PurposeWe attempted to evaluate the efficacy of femtosecond laser-assisted intrastromal corneal ring segment implantation in patients with keratoconus (KC).Patients and methodsA retrospective interventional consecutive clinical study was conducted on patients with KC who were treated with femtosecond laser Keraring implantation. All procedures were performed at Ebsar Eye Center in the period from January 5, 2015, to February 28, 2016.ResultsThirty eyes of 20 patients were included in this study. The mean age of patients was 27.43±3.57 years. Eleven patients (55%) were female and nine patients (45%) were male. Keraring segments were successfully implanted in all eyes. There were no complications or need for ring repositioning. The follow-up period was 6 months postoperatively. There was a significant improvement in the mean logarithm of the minimum angle of resolution (LogMAR) of uncorrected visual acuity (UCVA) after Keraring segment implantation from 1.5±0.23 preoperatively to 0.54±0.16 at 6 months postoperatively (P=0.001). The preoperative mean LogMAR of best-corrected visual acuity (BCVA) was 0.85±0.17. At 1 month postoperatively, it was 0.35±0.15; at 3 months postoperatively, it was 0.26±0.11, and at 6 months postoperatively, it was 0.14±0.07 (P=0.001). The mean preoperative maximum keratometric value for 3 mm pupil in diopters (K max) significantly decreased from 55.85±5.44 preoperatively (N=30) to 44.05±1.64 D at 6 months postoperatively (P=0.001). There was a statistically significant reduction in the mean preoperative spherical equivalent from −5.43±1.76 D preoperatively to −2.43±0.95 D at 6 months postoperatively. No statistically significant differences were detected between 1 and 3 months of follow-up regarding the visual and refractive outcomes.ConclusionAnalysis of the outcomes after Keraring ICRS implantation showed a significant postoperative corneal flattening with a subsequent increase in UCVA and BCVA. Using the femtosecond laser for tunnel creation made the procedure easy and fast with an accurate precise depth of implantation and reduced the risk of operative and postoperative complications.

Modification of the Intrastromal Ring Position according to Postimplant Visual and Refractive Failure: Report of Two Cases

“…To avoid melting, they repositioned the migrated segment away from the incision site with successful outcomes in all of the eyes. Heikal et al reported no complications or need for ring repositioning in a 6-month follow-up of 20 patients [12].…”

Intracorneal Ring Segment Implantation for the Management of Keratoconus in Children

“…Specifically, significant central corneal flattening, reduction of magnitude of astigmatism and improvement of CDVA were observed, with 52.8% of eyes showing a reduction in the magnitude of anterior corneal astigmatism of 1 D or more. Heikal et al [ 28 ] found in a sample of 20 adult keratoconus eyes implanted with KeraRing using the femtosecond laser technology that mean LogMAR CDVA improved from 0.85 ± 0.17 preoperatively to 0.26 ± 0.11 at 3 months postoperatively ( p = 0.001). Alfonso et al [ 13 ] reported in a sample of 118 eyes of 88 children a change of mean CDVA from 0.67 ± 0.37 logMAR preoperatively to a value of 0.37 ± 0.30 logMAR at 6 months after ICRS implantation.…”

Keratoconus Treatment Algorithm

“…ICRS implantation is a safe and reversible technique that can achieve corneal flattening and improved visual outcomes. Several factors such as the type of ICRS, the insertion technique, and patient selection contribute to the final outcome [ 28 ].…”