If the keratitis remains uncontrolled after adequate medication, the corneal stromal tissue continues to necrose and slough off due to a complex combination of bacterial toxins and immune factors, the ulcer continues to progress deeper and deeper, and furthermore, perforation of the corneal ulcer site can occur. If a therapeutic corneal transplant is not performed, the inflammation will rapidly expand into the eye, eventually leading to total ophthalmoplegia and loss of the eye. If a lamellar corneal transplant is chosen when the lesion has not yet invaded the entire cornea, the diseased tissue can be removed and postoperative immune rejection can be minimized. If the lesion has already involved the whole cornea, a penetrating corneal transplant is performed to completely remove the diseased tissue and control the inflammation to avoid corneal perforation and save the eye. However, since the corneal transplantation is performed when the eye is in a state of extreme congestion and inflammation, there is a possibility of recurrence of the inflammation after the surgery; moreover, the inflammation and congestion will increase the chance of immune rejection of the corneal transplantation. Therefore, the postoperative medication should be strictly followed, and timely follow-up.