Corneal Ulcer Management

10 Questions

What is one of the causes of inflammatory ulcer?

Vitamin A deficiency

What is the main symptom of an inflammatory ulcer due to exposure of the corneal nerve endings?

Neuralgic pain

What is the pathological process of an inflammatory ulcer?

Entry and adherence of organism to breached epithelium

What is a sign of an inflammatory ulcer?

Ulcer with irregular edge and necrotic floor

What is a complication of an inflammatory ulcer due to diffusion of bacterial toxins?

Anterior chamber activity

What is the characteristic of a typical inflammatory ulcer?

Central ulcer

What is a complication of an inflammatory ulcer that may cause 2ry angle closure Glaucoma?

Iris adheres to the back of the cornea

What is the fate of the iris in a complication of an inflammatory ulcer?

It prolapses through sudden large corneal perforation

What is the characteristic of the ulcer floor in an inflammatory ulcer?

Necrotic floor

What is a complication of an inflammatory ulcer that does not occur in children?

Bulging of Descemet's membrane

Study Notes

Corneal Ulcers

Causes: Leucoma adherent, Corneal staphyloma, Dense corneal opacity with iris adherent to the back of the scar
Characteristics:
- Irregular anterior chamber (AC)
- Irregular pupil
- Lost AC
- Weak ectatic corneal scar with iris adherent to the back of the cornea

Treatment

Indications for treatment:
- Large (> 1.5 mm), central ulcer
- Severe infection (hypopyon, endophthalmitis)
- Poor compliance
- Failure to improve
Treatment options:
- Broad-spectrum antibiotics (e.g., fluoroquinolone, vancomycin, ceftazidime)
- Cyclopentolate E.D, Atropine E.D to relieve ciliary body spasm (cyclitis)
- Tear substitutes (drops & gel) with preservative-free drops
- Oral vitamin A
- Aqueous suppressants (e.g., timolol E.D)
- PTK, keratoplasty
- Intravitreal antibiotics +/- vitrectomy

Corneal Perforation

Treatment options:
- Cyanoacrylate glue
  - Principle: Bridging corneal tissue gap to allow re-epithelialization and bacteriostatic effect
  - Indications: Corneal perforation (< 2 mm), corneal thinning (< 3 mm), central, concave, non-infected, progressive
  - Fate: Spontaneous dislodgement after re-epithelialization or removed gently after 6-8 weeks
- Fibrin glue:
  - Advantages: Solidify quickly, easy to apply, less discomfort
  - Disadvantages: Degrade faster, no bacteriostatic effect, risk of prion/viral diseases
- Amniotic membrane transplantation:
  - Advantages: Not invaded by blood vessels, ↓ scar tissue proliferation, no immune reaction, stimulate re-epithelialization, anti-inflammatory effects
- Conjunctival flap:
  - Advantages: Brings superficial blood vessels to promote healing, control pain, eliminate frequent medications
  - Contraindications: Active suppurative keratitis, eyes with frank perforation
- Tectonic keratoplasty:
  - Indications: Large (> 3 mm) corneal perforation
  - Timing: Delay keratoplasty for 3-5 days to allow sealing of perforation and restoration of AC

Influenza

Risk factors: Vit A deficiency, immunocompromised individuals
Pathology:
- Entry and adherence of organism to breached epithelium
- Multiplication and release of toxins and enzymes
- Epithelium casts off, giving an ulcer with irregular edge and necrotic floor
- Posterior abscess may form, causing descematocele or corneal perforation
- Diffusion of toxins causing iridocyclitis

Symptoms

Lacrimation due to corneal edema and iridocyclitis
Photophobia
Blepharospasm
Severe neuralgic pain due to exposure of corneal nerve endings

Signs

Edema
Loss of luster
Ulcer with necrotic tissue
+ve fluorescein stain
Ciliary injection
Hypopyon

Complications

Diffusion of bacterial toxins
Anterior chamber activity (cells and flare)
+/- Hypopyon
Bulging of Descemet's membrane (descematocele)
Iris adheres to the back of the cornea, causing 2ry angle closure glaucoma
Iris prolapses through sudden large corneal perforation