Purpose: To analyze the visual and refractive outcomes of combined accelerated cross-linking with
femtosecond laser intracorneal ring segment implantation for the treatment of pediatric keratoconus.
Materials and Methods: This retrospective multicenter noncomparative clinical study included 63 eyes
of 37 patients (age, 9–17 years) who underwent between August and September 2016 combined crosslinking
with intracorneal ring segment implantation for keratoconus. Preoperative and postoperative (6,
12, and 18 months) uncorrected distance visual acuity (UDVA) and corrected distance visual acuity
(CDVA), subjective refractions, keratometry (K), and pachymetry measurements were compared.
Results: The postoperative spherical equivalent refraction was within ±1 D, ±2 D, and ±3 D in 19 (30.2%),
27 (42.9%), and 37 (58.8%) eyes, respectively. Only 27 eyes achieved the attempted preoperative
spherical equivalent refraction. The mean spherical equivalent refraction significantly improved from
−6.01 ± 2.97 to −3.13 ± 2.78 D postoperatively (P < 0.0001). The mean K average reading significantly
decreased from 48.75 ± 4.25 to 46.65 ± 3.89 D postoperatively (P < 0.0001). The mean postoperative
myopic, astigmatic, and spherical equivalent corrections were −2.17 ± 2.19, −1.52 ± 2.03, and
−2.93 ± 2.35 D, respectively. The mean UDVA and CDVA showed significant improvements
(0.89 ± 0.33 to 0.40 ± 0.28, P < 0.0001; 0.35 ± 0.31 to 0.25 ± 0.24, P = 0.004; respectively) at 18 months
postoperatively. Keratoconus progression, segment migration, and segment extrusion were seen in four
(6.4%), one (1.6%), and three (4.7%) eyes, respectively, probably contributing to the lower mean postoperative
CDVA.
Conclusion: Cross-linking plus is only partially effective for pediatric keratoconus. Despite some
improvements in vision and keratometry measures, it resulted in complications such as keratoconus
progression, segment extrusion, and segment migration that affected the vision in some patients. These
findings suggest an assessment of standard epithelium-off collagen cross-linking as a sole procedure to
treat pediatric keratoconus in future studies. |
