Safety and efficacy of corneal cross-linking in pediatric patients with keratoconus and vernal keratoconjunctivitis

Abstract

PURPOSE:The purpose of the study is to determine the safety and efficacy of corneal collagen cross-linking for keratoconus in pediatric patients with and without vernal keratoconjunctivitis (VKC).METHODS:This is a retrospective analysis of 89 eyes of 58 patients <18 years of age that underwent corneal collagen cross-linking for progressive keratoconus; inclusion criteria included a minimum of 2-year follow-up after cross-linking. The main outcomes measures included keratometry, pachymetry, vision, and complications following epithelial-off cross-linking with the Dresden protocol.RESULTS:VKC patients were more likely to be male; 81.6% of the non-VKC patients and 96.3% of VKC patients were male (P = 0.038). Comparing pretreatment to the 2-year follow-up, there was no statistically significant change in the mean steep or flat keratometry, corneal thickness, and uncorrected visual acuity or best spectacle-corrected visual acuity in either group. There were no statistically significant differences in the mean visual, keratometric, or adverse event outcomes between the two groups. The proportion exhibiting progression of ectasia at 2 years was 18.5% in the VKC group and 16.7% in the non-VKC group (P = 0.83).CONCLUSIONS:Cross-linking appears to be as safe and effective in pediatric patients with vernal keratoconjunctivits as in those without, with similar outcomes, adverse events, and progression of keratoconus after treatment. The proportion of patients exhibiting progression appears to be higher in pediatric patients than adults, and there is an association between male sex and diagnosis of VKC.

Management Outcomes in Pediatric Keratoconus: Childhood Keratoconus Study

“…We also found that the presence of VKC did not affect the success of CXL. Similar results were reported with use of standard (Dresden protocol) CXL in pediatric KC eyes with VKC by Stone et al [ 28 ] in a two-year retrospective case-control study. The authors noted failure rate in 18.5% in VKC group and 16.7% in non-VKC group ( p =0.83).…”

Progression of Pediatric Keratoconus After Corneal Cross-Linking: A Systematic Review and Pooled Analysis

“…Change in Kmax was the most common criterion for progression in 25 studies (67.5%): A change over at least $1.0 diopter (D) was used in 23 studies (62.1%) which included 2 studies that reported on Kmax $ 1.5 D 24,27 and one study that reported on Kmax $ 2.0 D. 17 One study reported a change in Kmax $ 0.5 D 45 and one on a change in Kmax without any value given. 28 Adding the 6 studies that reported on a change in Ksteep (n = 5) and Kmean (n = 1) $1.0 D 8,11,18,23,29,35 to the 23 studies that reported a change in Kmax $1.0 D results in overall 78.3% of studies, which considered a change in K's values as a criterion of progression.…”

“…Change in corneal thickness (at least decreased of/in 10 mm or 2% from the baseline) was reported in 8 studies (21.6%) of which 3 reported it in the central 8,23,27 and 5 at the thinnest point. 5,11,17,24,45 Change in manifest refraction sphere was used in 3 studies (8.1%), and manifest refraction spherical equivalent was used in 4 reports (10.8%).…”

“…Change in corneal thickness (at least decreased of/in 10 μm or 2% from the baseline) was reported in 8 studies (21.6%) of which 3 reported it in the central 8,23,27 and 5 at the thinnest point. 5,11,17,24,45…”

Vernal keratoconjunctivitis and keratoconus

“…In addition, post-CXL progression of ectasia was not significantly different between both groups although it was slightly increased in the VKC group: 18.5% versus 16.7% in the non-VKC group. The authors concluded that CXL appears to be as safe and effective in pediatric patients with VKC as in those without [43]. In a study comparing transepithelial CXL (TE-CXL) with Keraring implantation versus TE-CXL alone for pediatric patients with VKC, Abozaid et al observed significant improvement of outcome indices in the group which had Keraring implants.…”