Corneal Stromal Abscesses

These flashcards cover key concepts related to corneal stromal abscesses, including definitions, pathogenesis, clinical signs, treatment options, and goals of therapy.

What are corneal stromal abscesses characterized by?

White to yellow opacities within the cornea resulting from the accumulation of inflammatory cells and products.

What is the pathogenesis of stromal abscesses?

Micropuncture traumatizes the corneal stroma, inoculating it with microbes or foreign bodies.

What triggers epithelial cell migration over a defect in the cornea?

The formation of an abscess after the absence of epithelial cells over the defect.

What is a key differential diagnosis for corneal stromal abscesses?

Uveitis, especially severe cases that obscure focal opacity in the cornea.

What are common clinical signs of corneal stromal abscesses?

Corneal opacity, edema, vascularization, and signs of uveitis, among others.

What types of organisms are commonly associated with stromal abscesses?

Fungal agents, foreign material, bacteria, and immune-mediated reactions.

What is the recommended medical treatment for stromal abscesses involving antifungals?

Topical antimicrobials, specifically antifungals like natamycin and azoles.

When should medical treatment for corneal stromal abscesses be discontinued?

When there is a change in corneal coloration, resolution of uveitis signs, and retreat of corneal blood vessels after 4-6 weeks.

Why is surgery indicated for some corneal stromal abscesses?

If the abscess persists or progresses despite medical therapy, or if there is severe uveitis threatening vision.

What is the goal of therapy for corneal stromal abscesses?

To control uveitis, improve comfort, clear the cornea, and return vision and function.

Which clinical signs indicate secondary reflex uveitis in abscess cases?

Miosis (constricted pupil), aqueous flare, and decreased intraocular pressure.

What ocular behaviors often point toward a stromal abscess?

Blepharospasm (squinting), epiphora (excessive tearing), and photophobia (light sensitivity).

What role does topical atropine (1\%) play in managing corneal stromal abscesses?

It acts as a cycloplegic to reduce pain from ciliary muscle spasms and as a mydriatic to prevent posterior synechiae.

Why are systemic nonsteroidal anti-inflammatory drugs (NSAIDs) used in treatment?

To manage the intense secondary uveitis and provide systemic analgesia without the risks associated with topical steroids.

What surgical option is preferred for very deep stromal abscesses?

Deep lamellar endothelial keratoplasty (DLEK) or penetrating keratoplasty (PK).

How does the clinical appearance of the cornea change as a stromal abscess resolves?

The opacity becomes more focal and discrete, corneal edema subsides, and neovascularization begins to regress.

What determines the frequency of topical medication administration for a stromal abscess?

The severity of the abscess and the causative agent; initially, medications may be administered as often as every 1-2 hours.