•Inflammatory disease of the peripheral cornea: peripheral stromal infiltrates with epithelial defect and ulceration. •Associated with the presence of blepharoconjunctivitis. Due to an inflammatory response against S. aureus antigens. Etiology: •Symptomatic Staphylococcal blepharitis/conjunctivitis, or asymptomatic Staphylococcal colonization of the eyelid. Pathophysiology: •The presence of bacterial antigens in the peripheral area of the cornea triggers a type III hypersensitivity reaction, in which immunocomplexes are formed and deposited in the peripheral corneal stroma. •There is a complement pathway activation and neutrophil attraction, with the formation of a peripheral stromal opacity also called catarrhal infiltrate. •This lesion may evolve with epithelial damage, forming a marginal ulcer. •The lesions usually appear in direct contact with the peripheral cornea and eyelid margin. Risk Factors: •Longstanding blepharitis, conjunctivitis, or meibomitis. Signs: •1 or more stromal infiltrates in the peripheral cornea, typically in the points of intersection between the eyelid margin and the limbus (i.e. 2, 4, 8, and 10 o’clock positions). •Located 1-2mm parallel to the limbus, with a clear margin of healthy cornea between them. •Spread and coalesce circumferentially, with little tendency to grow centrally or peripherally. •With prolonged inflammation, there can be an epithelial defect, leading to the formation of a marginal ulcer. •Erythema and edema of the eyelid margin with telangiectasias. •Eyelash changes: madarosis, poliosis, trichiasis, and the presence of hard scales in the base of eyelashes, are more specific findings of the long-standing S. aureus blepharitis. •In severe cases: removal of these scales from the eyelid margin can cause ulceration. Diagnosis: •Slit lamp examination. •Corneal scraping. D/D: •Herpetic stromal keratitis •PUK •Mooren’s Ulcer Management: •Topical corticosteroids: in peripheral stromal infilwithout epithelial defects along with topical broad spectrum antibiotics. •Treatment for blepharitis: adequate eyelid hygiene, topical antibiotic ointments, oral antibiotics(doxycycline, tetracycline). www.ophthalmobytes.com Image from Rajan Eye Care Hospital #ophthalmology#ophthal#doctor#health#medical#vision#education#optometry#medicalstudent#optometrist#medicine#eye#ophtho#ophthalmologist#ophthalmo#med#medicaleducation#ophthalmologyresident#ophthalmologyresidency#oftalmologia#surgery#surgeon#apaoyo #cornea #keratitis#marginalkeratitis