Long-term visual and topographic outcomes are often stable 10 years after undergoing corneal crosslinking (CXL) for progressive keratoconus or other corneal ectasias, according to research published in Eye & Contact Lens. Overall, eyes with keratoconus appear to demonstrate greater stability compared with eyes with other corneal ectasias, according to the report.
Researchers included 13 individuals (eyes, 19; average age, 33.7 years) who underwent the CXL procedure at a single center a mean 10.8 years prior to the investigation in the cross-sectional cohort study. A total of 11 eyes had keratoconus, and the remaining 8 had other corneal ectasias. The team evaluated long-term visual and topographic outcomes among the cohort, and participants underwent uncorrected and best-corrected spectacle visual acuity, maximum keratometry (Kmax), and thinnest pachymetry (Pthin) measurements 1 and 10 years following CXL. The investigators also determined anterior curvature, posterior curvature, and corneal thickness progression using the Belin ABCD progression display.
Topographical analysis shows that Kmax values decreased from 58.2 diopters (D) preoperatively to 55.4 D 1 year following the procedure. These values increased to 58.3 D at the 10-year follow up. Anterior and posterior curvature progressed in 5 eyes, and this change was more frequently observed in eyes with other corneal ectasias compared with eyes with keratoconus (n=4 vs n=1).
Average Pthin values increased from 440.6 µm preoperatively to 442.5 µm at 1 year and remained stable at the 10-year follow-up visit (442.3 µm). Overall, corneal thickness progressed in 9 eyes compared with preoperative values, according to the report.
Long-term visual acuity outcomes were better among eyes with keratoconus compared with other corneal ectasias, the report shows. Uncorrected visual acuity worsened by more than 2 lines in 42.1% of the entire cohort, 18.2% of individuals with keratoconus, and 75% of individuals with other corneal ectasias. Best corrected spectacle visual acuity worsened by more than 2 lines in 13.8%, 0.0%, and 37.5% of the same respective eyes.
“All patients undergoing cross-linking treatment should be counseled about the long-term stability of the procedure and should be advised of the importance for continued regular follow-up examinations after treatment,” according to the study authors. “In particular, patients with corneal ectasia after laser refractive surgery should be counseled on the possible increased risk of progression after CXL and the need for future cross-linking retreatment.”
Study limitations include a small sample size of participants who returned for assessment of the long-term visual and topographic outcomes.
Greenstein SA, Yu AS, Gelles JD, Huang S, Hersh PS. Long-term outcomes after corneal cross-linking for progressive keratoconus and corneal ectasia: a 10-year follow-up of the pivotal study. Eye Contact Lens. Published online August 8 2023. doi:10.1097/ICL.0000000000001018