This clinical study was conducted to evaluate the efficacy and safety of gold-silver cuprous oxide composite nanogels combined with photothermal therapy system in the treatment of severe drug-resistant bacterial keratitis ineffective by traditional antibiotic treatment in human eyes, and to provide translational applications. Based on the clinical evidence, a more effective and safe innovative treatment plan for corneal diseases has been developed.

Inclusion Criteria:

1. The monocular cases of severe infectious keratitis admitted to our center were diagnosed as fungal keratitis according to their medical history, physical signs and surface secretions smear examination of corneal ulcer lesions (severe was defined as subjects with visual acuity < 0.15, deep stromal infiltration or involvement diameter >2mm, with extensive infiltration around or with extensive suppuration)
2. After more than 2 weeks of active treatment with antibiotics, there was no effect
3. The researchers communicated with the subjects in detail, and the subjects cooperated well and they voluntarily participated and signed informed consent

Exclusion Criteria:

1. Allergic to the drug in this test.
2. Pregnant and lactating women.
3. The medical history suggests serious heart, lung, liver, kidney dysfunction.
4. Patients with other factors that would affect the results of this result.
5. No signed informed consent.