Abstract
Purpose:
To investigate the early clinical results of transepithelial corneal collagen cross-linking using iontophoresis (I-CXL) technique for keratoconus.
Methods:
78 eyes of 63 patients diagnosed as progressive keratoconus, whose thickness were more than 400μm at the thinnest point, were included in this study and underwent I-CXL. Slit lamp examination, corneal epithelial fluorescein staning, uncorrected distance visual acuity (UCDVA), corrected distance visual acuity (CDVA), spherical equivalent and cylinder refraction, Orbscan II tomography parameters, anterior segment optical coherence tomography (AS-OCT), endothelial cell count and confocal laser scanning microscopy were assessed at baseline and at 1, 3, 6, and 12 months postoperatively.
Results:
Mean age of the patients was 19.3 years. Mild corneal epithelial defect was observed within one to three days postoperatively, and recovered rapidly with mild pain. There was an improvement in the mean postoperative UCDVA, mean CDVA, mean spherical refraction, mean cylinder, and spherical equivalent. Four patients with vernal keratoconjunctivitis or corticosteroid glaucoma showed progression. There was no intra- or postoperative complications except temporary corneal epithelial defect. Corneal endothelial count remained stable without significant decrease. AS-OCT and confocal laser scanning microscopy showed the collagen cross linking effects and diverse cell apoptosis in the anterior stroma with deepest 260μm in average.
Conclusions:
Preliminary results up to 1 year postoperatively indicated that I-CXL was effective and safe in stabilizing the progression of keratoconus. I-CXL has the potential to become a valid alternative for halting the progression of keratoconus while reducing postoperative patient pain, risk of infection, and treatment time in selected patients.