Corneal ring segments insertion in cross-linked keratoconus corneas versus virgin corneas: a multi-parameter matched comparison
First Author: S.Awwad LEBANON
Co Author(s): K. Kozhaya N. El Salloukh N. Nasser L. Asroui
To retrospectively evaluate the visual, refractive, and tomographic results of intracorneal ring segments (ICRS) insertion in keratoconus eyes with a previous history of corneal cross-linking (CXL), compared to virgin eyes.
Department of Ophthalmology, American University of Beirut Medical Center, Beirut, Lebanon.
A retrospective analysis of 228 eyes with mild to moderate keratoconus who underwent ICRS was conducted. Only 30 eyes had undergone previous CXL, hence the rest of the eyes were matched to this group, based on type and segment size, age, SimK, Kmax, pachymetry, topographic and manifest astigmatism, and manifest spherical equivalent refraction. The final comparison groups were 60 virgin keratoconus eyes and 30 post-CXL keratoconus eyes. Primary outcome measures preoperatively, and at 1, 3, and 6 months postoperatively, included uncorrected and distance-corrected visual acuity (UCVA and DCVA), manifest sphere and cylinder, SimK and Kmax, and corneal higher order aberrations.
The LogMAR UCVA for the ICRS and ICRS-CXL groups improved from 0.74±0.23 to 0.37±0.27, and 0.61±0.27 to 0.41±0.29 respectively, while LogMAR CDVA improved from 0.43±0.20 to 0.15 ± 0.19, and 0.31±0.16 to 0.10 ± 0.12 respectively, (P<0.01), and Kmax improved from 53.57±4.16 D to 49.64±4.06 D and 53.59±4.85 D to 49.09±5.23 D, respectively (P<0.01). Manifest cylinder improved from 3.31 ± 1.50 D to 1.56±1.33, and 3.76±1.28 D to 1.01±0.87 D, respectively (P<0.01). SimK changed from 45.88±1.96 D to 44.46±2.28 D, and 45.5±3.08 D to 44.21±3.09 D. No clinically relevant intraoperative or postoperative complications were observed in either group.
Corneal ring segments insertion in keratoconus eyes with previous corneal cross-linking have similar visual, refractive, and topographical results as virgin eyes.