A contact-lens wearer wakes with severe eye pain and pus — bacterial corneal ulcer; fortified antibiotics hourly. Bacterial keratitis (contact lens overwear, trauma — severe pain, redness, corneal opacity, hypopyon — pus in anterior chamber): corneal scraping for culture, then fortified antibiotics hourly — the cornea melts fast. Fungal (vegetative trauma — feathery edges, natamycin). Viral HSV (dendritic branching ulcer — fluorescein; acyclovir; steroids worsen — contraindicated). Corneal transplant/keratoplasty (scarred cornea — eye donation after death; sutured graft; rejection — steroids). The painful white spot is the ulcer — scrape, culture, treat hourly.