The use of corneal collagen crosslinking (CXL) may extend beyond keratoconus management, a new study suggests. As an adjuvant therapy to standard antimicrobial treatment, researchers recently found that photoactivated chromophore for infectious keratitis (PACK)-CXL improves visual outcomes in patients with treatment-resistant corneal ulcers.

This observational cohort study evaluated 42 eyes of 41 patients with treatment-resistant infectious keratitis. All eyes underwent PACK-CXL treatment with the Dresden modified protocol in addition to standard antimicrobial therapy.

On the first day post-op, 16.67% of the eyes showed ulcer growth, while the remainder did not experience a change in size. At week one and months one and three, each of the ulcers either decreased in size (76.19%, 85.71%, 14.28%, respectively) or remained the same compared with the previous time point.

After three months post-op, the team reported a success rate of 90.5% and indicated that the treatment effect increased with time. Statistical analysis showed that PACK-CXL combined with standard antimicrobial therapy was able to significantly reduce overall corneal ulcer size.

“The healing rates obtained with PACK-CXL are unprecedented,” the study authors wrote in their paper. They hope their findings prompt wider use of this procedure in cases unresponsive to standard therapy, especially taking into account the necessity of new lines of treatment as microbial resistance to antibiotics increases.

“PACK-CXL may be a promising new alternative and its use is recommended due to the potential benefit obtained by controlling infection regardless of drug resistance, stopping the melting process, avoiding emergency keratoplasty and decreasing the possibility of performing lamellar grafts for visual rehabilitation,” the investigators concluded.

Gulias-Cañizo R, Benatti A, De Wit-Carter G, et al. Photoactivated chromophore for keratitis-corneal collagen crosslinking (PACK-CXL) improves outcomes of treatment-resistant infectious keratitis. Clin Ophthalmol. 2020;14:4451-7.