Conjunctival goblet cells secrete mucin, vital for tear film stability. Dysfunction can cause tear film issues and lead to diseases like dry eye. Imaging these cells is crucial for diagnosis and treatment. 0.5% moxifloxacin eye drops, an FDA-approved antibiotic, are used to treat bacterial eye infections and prevent infections before surgeries. The investigators developed a non-invasive imaging method for goblet cells, validated in animals, and now plan to test it in humans for diagnosing and treating ocular surface diseases.

Conjunctival goblet cells secrete mucin on the ocular surface, playing a role in forming the mucin layer of the tear film. The mucin layer is crucial for maintaining tear film stability, and dysfunction of conjunctival goblet cells can lead to instability of the mucin layer, causing problems in the tear film. Because various ocular surface diseases stem from tear film instability, imaging of conjunctival goblet cells is essential for diagnosing and treating conditions such as dry eye.

0.5% moxifloxacin eye drops are FDA-approved antibiotics belonging to the quinolone class, widely used to treat bacterial infections in various ocular diseases. Clinically, 0.5% moxifloxacin eye drops are commonly used for purposes such as secondary infection prevention in cases of corneal epithelial defects or perforations caused by ocular surface diseases, as well as for prophylaxis prior to various ophthalmic surgeries, including cataract surgery.

The investigators have previously pioneered non-invasive, high-speed, high-contrast imaging of conjunctival goblet cells. Previous studies have validated the performance and safety of this method by imaging conjunctival goblet cells in mice and rabbit animal models after the instillation of moxifloxacin and illuminating with a 405nm light source using confocal fluorescence microscopy. Furthermore, in this study, the investigators plan to conduct a study involving human subjects to apply our developed conjunctival goblet cell imaging technique for the diagnosis and evaluation of treatment outcomes in ocular surface diseases.

Inclusion Criteria:

• Adult patients aged 19 years or older.
• Patients who are currently using or scheduled to use 0.5% moxifloxacin eye drops for ophthalmic surgery (control group) or for ocular surface diseases (patient group: dry eye, Sjogren's syndrome, Stevens-Johnson syndrome, graft versus host disease).
• Patients who have agreed to understand and comply with the clinical trial protocol's plans for medical examinations and follow-up observations.

Exclusion Criteria:

• Pregnant or planning to become pregnant, and lactating women.
• Patients with intellectual disabilities and other psychiatric disorders who, at the discretion of the investigator, are deemed ineligible for participation in the clinical trial.
• Patients with hypersensitivity reactions to 0.5% moxifloxacin eye drops, or patients for whom administration is contraindicated.
• Patients for whom participation in the study is deemed impractical based on the judgment of other medical staff and neutral observers (excluding specified selection/exclusion criteria, based on medical reasons, ethical considerations, low compliance, and understanding of the study).