Peripheral corneal changes and alterations

Dellen

  • Localized, saucer-like thinning (compacted stroma) of the peripheral cornea.

  • Due to tear film instability.

  • Affects the limbal cornea adjacent to a raised lesion (pingueculum, pterygium, episcleritis nodule, dermoid cyst, surgery, CL wear, dryness).

Treatment

  • Remove/treat the cause.

  • Non-preserved lubricants.

Marginal Keratitis

  • Common hypersensitivity to Staph toxins (usually from chronic adnexal disease).

Signs/Symptoms

  • Irritation/pain, redness, photophobia, lacrimation.

  • Peripheral, sterile sub-epithelial infiltrates with no overlying epi defect.

  • Circumferential spread.

  • Little staining.

  • Clear cornea to the limbus.

  • Vascularization across the limbus.

Treatment

  • Topical 0.5% chloramphenicol gutt AND 0.5% prednisolone gutt (or fluorometholone acetate 0.1%), both q6h, should lead to a resolution within 10 days.

  • Stringent attention to the eyelid margin disease.

  • Oral doxycycline 100mg for three months.

Rosacea Keratitis

  • Rosacea: long-term skin condition that typically affects the face.

  • More common in middle-aged women (but possible at any age).

  • Cheek and forehead flush (masked with makeup).

  • Rhinophyma in men.

  • Worsened by spicy food, alcohol, sun, emotional stress, and hot weather.

  • Ocular involvement: 18% of cases (blepharoconjunctivitis and keratitis (10%)).

Signs/Symptoms

  • Punctate epithelial keratopathy.

  • Inferior peripheral neovascularization.

  • Recurrent erosions.

  • Corneal thinning and perforation (rare).

Treatment

  • Weak topical steroid and short course of broad-spectrum antibiotic for blepharitis.

  • Systemic tetracycline (doxycycline).

  • 0.05% cyclosporine for ocular rosacea.

  • not curative → focused on management

Rhinophyma

Phlyctenular Disease

  • Delayed hypersensitivity reaction to bacterial antigens.

  • Developed world: mostly in children, Staph blepharitis.

  • Developing world: helminth and TB.

  • More frequent in children and young adults.

Signs/Symptoms

  • Pinkish/yellow (then grey/white) inflammatory lesion just inside the limbus (or on, or outside).

  • Bridging localized vascularization.

  • Photophobia, lacrimation, irritation.

Treatment

  • Eradicate causative organism.

  • Topical steroid (FML acetate 0.1%).

  • Staph coverage with ciprofloxacin.

  • Systemic doxycycline if Staph phlyctens are persistent.

  • If the patient has visited an area where TB is endemic, they should be referred for a chest X-ray and Mantoux test.

Terrien’s Marginal Degeneration

  • Uncommon.

  • Most cases are male, usually over 40.

  • Bilateral, slow progression.

Signs/Symptoms

  • Superior nasal (usual) thinning of the peripheral corneal stroma with an intact epithelium.

  • Upper corneal punctate stromal opacities, mild vascularization, gutter formation, circumferential spread.

  • Vision loss from irregular astigmatism.

  • Typically patients are asymptomatic.

Treatment

  • Rigid CLs for irregular astigmatism.

  • Inflammatory episodes can be managed with prednisolone acetate or lotemax (loteprednol - significant IOP rise less common).