Results of corneal collagen cross-linking in patients with corneal ectasia after laser refractive surgery-A prospective study.

PURPOSE: To evaluate the safety and efficacy of epithelium-off (epi­off) corneal cross-linking (CXL) in patients with post-LASIK corneal ectasia (PLE) SETTING: Private clinical practice DESIGN: Prospective clinical trial METHODS: 82 eyes of adult patients post-LASIK, ages 21-67, with a topography pattern consistent with corneal ectasia, corrected distance visual acuity (CDVA) worse than 20/20, and minimum corneal pachymetry > 400 µm underwent epi­off CXL. Exclusion criteria were patients with corneas that were thinner than 400 µm or demonstrated central corneal scarring, history of herpetic eye disease, pregnancy or nursing. Follow up examinations of spherical equivalent, uncorrected distance visual acuity (UDVA), CDVA, steep keratometry (KSteep) and minimum pachymetry occurred on different but highly overlapping subsets of the operated eyes yearly until 5 years post-CXL. RESULTS: Over the 5 years of follow up, spherical equivalent did not significantly change while UCVA and CDVA stabilized or improved to a non-significant degree. KSteep and minimum pachymetry continued to be decreased to a statistically significant degree (p < 0.05 at 5 years). CONCLUSIONS: CXL in PLE patients is safe and efficacious: it halts progression of PLE and may improve visual function. KSteep and minimum pachymetry decrease post-CXL. Patients with PLE should be encouraged to stop progression of the disease by undergoing epi­off CXL once progression is established.

Results of corneal crosslinking in adolescents with progressive keratoconus: prospective study.

PURPOSE: To evaluate the safety and efficacy of epithelium-off (epi-off) corneal crosslinking (CXL) in adolescents with progressive keratoconus (KC). SETTING: Private clinical practice. DESIGN: Nonrandomized prospective clinical trial. METHODS: 230 adolescent patients aged 10 to 19 years with progressive KC (increasing maximum keratometry [Kmax] or astigmatism of 1.00 diopter or greater associated with decreased corrected distance visual acuity [CDVA]) underwent CXL. Exclusion criteria were age at time of CXL younger than 10 years or older than 19 years, corneas that were thinner than 400 µm or demonstrated central corneal scarring, history of herpetic eye disease, or pregnancy or nursing. Follow-up examinations of uncorrected distance visual acuity (UDVA), CDVA, Kmax, and minimum pachymetry occurred on 130 eyes at 1 year, 77 eyes at 2 years, and 55 eyes at 3 years post-CXL. RESULTS: In this study, 230 eyes of adolescent patients were evaluated. UDVA significantly improved from preoperatively to 1 year, 2 years, and 3 years post-CXL. CDVA values significantly improved from preoperatively to 1 year, 2 years, and 3 years post-CXL. Kmax values significantly reduced (improved) from preoperatively to 1 year and 3 years post-CXL and reduced (improved) (P = .22) from preoperatively to 2 years post-CXL. Minimum pachymetry decreased significantly from preoperatively to 1 year, 2 years, and 3 years post-CXL. CONCLUSIONS: CXL in patients aged 10 to 19 years was safe and efficacious, halted progression of KC and could improve UCVA, CDVA, and Kmax. Minimum pachymetry decreased and stabilized post-CXL. Ophthalmologists should encourage adolescent patients with KC to obtain prompt evaluation and possible CXL to halt progression of the disease.

Refractive Errors and Amblyopia Among Children Screened by the UCLA Preschool Vision Program in Los Angeles County.

PURPOSE: To summarize the results of 5 years of vision screening with the University of California, Los Angeles (UCLA) Preschool Vision Program (UPVP). DESIGN: Retrospective evaluation of a screening program. METHODS: The UPVP performed visual acuity and undilated noncycloplegic refractive screening using an autorefractor on 93,097 children between 2012 and 2017. Of these, 79,451 children, who were between 3 and 5 years old, were screened for the first time, and 14,259 were referred for full cycloplegic examination if they met specific refractive criteria for myopia, hyperopia, astigmatism, or anisometropia. UPVP performed 6779 cycloplegic examinations on this population. Data from the right eye only were included in this analysis. RESULTS: Of the examined population, hyperopia was found in 61% (4018), myopia in 20% (1336), and astigmatism in 93% (6122) of children. Latino children had higher rates of astigmatism and worse visual acuity compared to all other races/ethnicities. An astigmatism cutoff of ≥1.50 diopters (D) in either eye correctly predicted the need for glasses 93% of the time; increasing this cutoff to ≥1.50 D in both eyes increased the positive predictive value to 96%. Refractive amblyopia was found in 780 children (1.0% of the screened population and 11.5% of the examined population), and of these, 211 (27%) were bilaterally amblyopic. CONCLUSIONS: These data represent the largest published sample of vision screening results on preschool-aged children, provide additional insight on the proportion of common refractive errors and their association with race/ethnicity, and can inform screening criteria to more accurately identify children who need intervention to prevent permanent vision loss.

Corneal Perforation After Corneal Cross-Linking in Keratoconus Associated With Potentially Pathogenic ZNF469 Mutations.

PURPOSE: To report a case of bilateral and repetitive corneal perforations after corneal cross-linking (CXL) for keratoconus in a woman harboring potentially pathogenic variants in the ZNF469 gene and to characterize the keratoconus phenotype in this woman and her daughter who shared the same ZNF469 mutations. METHODS: Clinical characterization of the proband and her daughter followed by sequencing of the genes associated with brittle cornea syndrome, ZNF469 and PRDM5, in both individuals. RESULTS: An Ashkenazi Jewish woman in her sixth decade presented with diffuse corneal thinning and progressive steepening consistent with keratoconus. After CXL, epithelium-off in the first eye and epithelium-on in the second, she developed spontaneous corneal perforations in each eye. Her daughter in her fourth decade demonstrated a similar pattern of diffuse corneal thinning and progressive corneal steepening but did not undergo CXL and did not develop corneal perforation. Screening of the ZNF469 and PRDM5 genes revealed 3 missense ZNF469 variants (c.2035G>A, c.10244G>C, and c.11119A>G) in cis arrangement on 1 allele of ZNF469 in both proband and her daughter. Although the 3 variants share low (<0.01) global minor allele frequencies, each has significantly higher minor allele frequencies (0.01-0.03) in the Ashkenazi Jewish population, leading to uncertainty regarding a pathogenic role for the identified variants. CONCLUSIONS: CXL may be associated with the development of corneal perforation in particular at-risk individuals with keratoconus. Identifying clinical and genetic risk factors, including screening of ZNF469 and PRDM5, may be useful in the prevention of significant complications after CXL.