Nonetheless, we acknowledge that systemic therapy may have contributed to the overall improvement and that causality cannot be definitively established. That said, while the corneal ulcer may have had residual healing potential, the complete re-epithelialization within three days following insulin initiation, after two weeks of non-response to conventional therapy, suggests a contributory, if not primary, role for topical insulin in this case. Here, INS is linked to corneal infection.