A 28-YEAR-OLD woman complained of reduced vision in her left eye. She had a history of keratoconus and had undergone epikeratoplasty 5 years earlier. Following that procedure, she was diagnosed as having an interface infection and was treated with topical antibiotics. At examination, her visual acuity was 20/100 OS. A 3 × 4-mm flat, opalescent lesion was seen in the donor-recipient interface (Figure 1). The lesion enlarged, and penetrating keratoplasty was performed. The visual acuity subsequently improved to 20/25 OS.