Phase III clinical trial examines new ways to succeed with transepithelial procedure
Our practice has been performing epi-off corneal collagen cross-linking (CXL) since it was approved by the U.S. Food & Drug Administration (FDA) for patients with progressive keratoconus or ectasia.
This has been such an exciting procedure for us to offer. For the first time, eyecare practitioners have been able to provide a treatment that can slow or halt the progression of ectatic disease rather than just managing it until patients get to the point of needing a corneal transplant.
I have also seen a number of patients treated early in the disease course who have continued to be successful in glasses or soft contact lenses without being dependent on specialty contact lens fits.
Despite these positive outcomes, there are potential improvements over the way the procedure is currently performed.
Because the surgeon creates a large epithelial defect, the first few days after the procedure can be uncomfortable for patients, and it can take several days for the epithelium to heal. Until the epithelium heals, the eye is more vulnerable to haze or infection, although the risk of these complications is low.1,2
Many people think transepithelial or “epi-on” CXL has the potential to speed visual recovery and improve the patient experience.
1. O’Brart DPS. Corneal collagen crosslinking for corneal ectasias: A review. Eur J Ophthalmol. 2017;27(3):253-69.
2. Hersh PS, Stulting RD, Muller D, et al; U.S. Crosslinking Study Group. United States multicenter clinical trial of corneal collagen crosslinking for keratoconus treatment. Ophthalmology. 2017; 124(9):1259-70.
3. Kobashi H, Rong SS, Ciolino JB. Transepithelial versus epithelium-off corneal crosslinking for corneal ectasia. J Cataract Refract Surg. 2018;44:12:1507-16.
4. Hill J, Liu C, Deardorff P, et al. Biomechanical impact of drug formulation, supplemental oxygen, and UV delivery on epi-on CXL. Presentation at Association for Research in Vision & Ophthalmology, April 27-May 2, 2019, Vancouver, British Columbia, Canada.
5. Ostacolo C, Caruso C, Tronino D, et al. Enhancement of corneal permeation of riboflavin-5’-phosphate through vitamin E TPGS: A promising approach in corneal trans-epithelial cross linking treatment. Int J Pharm. 2013;440:148-53.
6. Stulting RD, Trattler WB, Woolfson JM, et al. Corneal crosslinking without epithelial removal. J Cataract Refract Surg. 2018;44:1363-70
7. Rubinfeld RS, Caruso C, Ostacolo C. Corneal cross-linking: The science beyond the myths and misconceptions. Cornea. 2019;38(6):780-90.
8. Buzzonetti L, Petrocelli G, Valente P, et al. Iontophoretic transepithelial collagen cross-linking versus epithelium-off collagen cross-linking in pediatric patients: 3-year follow-up. Cornea. 2019;38(7):859-63.
9. Sun L, Li M, Zhang X, et al. Transepithelial accelerated corneal collagen cross-linking with higher oxygen availability for keratoconus: 1-year results. Int Ophthalmol. 2018;38(6):2509-17.
10. Hill J, Liu C, Deardorff P, et al. Stromal oxygen dynamics during high-irradiance epi-on corneal crosslinking. Presentation at Association for Research in Vision & Ophthalmology, April 27-May 2, 2019, Vancouver, British Columbia, Canada.