Korean J Ophthalmol.  2019 Dec;33(6):528-538. 10.3341/kjo.2019.0088.

Effect of Sequential Intrastromal Corneal Ring Segment Implantation and Corneal Collagen Crosslinking in Corneal Ectasia

• Kim CY
• Kim MK

• KMID: 2465133
• DOI: http://doi.org/10.3341/kjo.2019.0088

Abstract

PURPOSE
To assess the clinical efficacy of sequential intrastromal corneal ring segment (ICRS) implantation and corneal crosslinking (CXL) in corneal ectasia.
METHODS
To assess the clinical efficacy of sequential intrastromal corneal ring segment (ICRS) implantation and corneal crosslinking (CXL) in corneal ectasia.
RESULTS
Greater improvement in uncorrected visual acuity was observed in the ICRS + CXL group than in the ICRS or CXL alone groups at both 6 (p = 0.008) and 12 months (p = 0.028). Refractive errors of sphere and spherical equivalent were significantly reduced in both the ICRS (p = 0.002 at 6 months, p = 0.004 at 12 months) and ICRS + CXL groups (p < 0.001 at both 6 and 12 months). Keratometric values including the maximum, minimum, and average were significantly reduced in all 3 groups at postoperative 6 and 12 months; however, the greatest reductions were observed in the ICRS + CXL group (all p < 0.001).
CONCLUSIONS
ICRS implantation followed by CXL within 1 month seems to be effective, and may be superior to ICRS or CXL alone in improving visual acuity and reducing refractive errors and keratometric values.

Keyword

Cornea; Crosslinking; Intrastromal corneal ring segment; Keratoconus; Post-laser in situ keratomileusis ectasia

MeSH Terms

Collagen*
Cornea
Dilatation, Pathologic*
Keratoconus
Refractive Errors
Treatment Outcome
Visual Acuity
Collagen

Figure

• 

  Fig. 1 Inter-group analyses of (A) best-corrected visual acuity (BCVA) and (B) uncorrected visual acuity (UCVA) changes in the intrastromal corneal ring segment (ICRS) group, corneal crosslinking (CXL) group, and ICRS plus sequential CXL group (ICRS + CXL) at each postoperative follow-up. logMAR = logarithm of minimum angle of resolution. p-values from Kruskal-Wallis tests for inter-group analyses at each follow-up are shown.

• 

  Fig. 2 Inter-group analyses of (A) sphere, (B) cylinder, and (C) spherical equivalent changes in the intrastromal corneal ring segment (ICRS) group, corneal crosslinking (CXL) group, and ICRS plus sequential CXL group (ICRS + CXL) at each follow-up. D = diopters. p-values from Kruskal-Wallis tests for inter-group analyses at each follow-up are shown.

• 

  Fig. 3 Inter-group analyses of corneal topographic changes in (A) maximum keratometry (Kmax), (B) minimum keratometry (Kmin), (C) average keratometry (Kavg), and (D) astigmatism in the intrastromal corneal ring segment (ICRS) group, corneal crosslinking (CXL) group, and ICRS plus sequential CXL group (ICRS + CXL) at each postoperative follow-up. D = diopters. p-values from Kruskal-Wallis tests for inter-group analyses at each follow-up are shown.

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