Conjunctiva 5

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  • 1.Ophthalmia nodosa
    • Nodular conjunctivitis due to irritation caused by caterpillar hairs
  • Small semitranslucent, reddish or yellowish-grey nodules are formed on the conjunctiva, cornea and sometimes in the iris
  • Microscopic examination shows hairs surrounded by giant cells and lymphocytes
  • Treatment : excision of conj nodules containing the hairs, antibiotics, cyclopegics

2. Allergic catarrhal conjunctivitis

  • Most common form of ocular and nasal allergy
  • Cinical subtypes:
  • 1.Acute allergic conjunctivitis : immediate reaction to allergens
  • 2. Seasonal allergic rhinoconjunctivitis : conjunctivitis part of hay fever, during the summer common allergens are pollens or certain flowers (primula, etc) elevated IgE levels in plasma and tears.
  • 3. Perennial allergic rhinoconjunctivitis : causes symptoms throughout the year with exacerbation in the autumn when exposure to dust mites and fungal allergens is greatest.
  • Other allergens: animals (horses, cats), chemicals, cosmetics, eyelash dyes , drugs (atropine, brimonidine allergy)

3. Acute allergic catarrhal conjunctivitis

  • Presentation : transient, acute attacks of redness, watering and itching associated with sneezing and nasal discharge. (hyperemia is less marked, watery secretion not purulent, containing eosinophils, tendency for subacute recurrences on renewed contact with the allergen)
  • Signs :
  • - lid edema
  • - conj has milky or pinkish appearance due to edema and injection
  • - small papillae may be present on upper tarsal conj.
  • Treatment :
  • - Removal of allergen from the environment
  • - Desensitization by course of injections
  • - topical mast cell stabilizers (nedocromil, Iodoxamide, ketotifen)
  • - topical antihistamines ( levocabastine, azelastine, emedastine)
  • - both antihistamine and mast cell stabilizer (Olopatadine 0.1% BD)
  • - Topical steroids short course (Loteprednol etabonate 0.5% QID)

4. Acute allergic catarrhal conjunctivitis 5. Acute allergic catarrhal conjunctivitis 6. Vernal keratoconjunctivitis (spring catarrh)

  • Recurrent, bilateral, external ocular inflammation, primarily affecting boys and young adults living in warm,dry climates
  • Occurs with the onset of hot weather (summer), rather than a spring complaint
  • Family history of atopy is common
  • Patients may develop asthma and eczema in infancy
  • Type I hypersensitivity reaction to pollen and other atmospheric exogenous allergens mediated by IgE (eosinophilia).
  • Onset is usually after the age of 5 years and condition resolves around puberty.
  • May occur on a seasonal basis/ may persist year round

7. Vernal keratoconjunctivitis (spring catarrh)

  • Symptoms : intense ocular itching, lacrimation, photophobia, foreign body sensation, burning, white ropy discharge
  • 3 main clinical types :
  • 1. Palpebral VKC:
  • 2. Limbal VKC
  • 3. Mixed VKC

8. Vernal keratoconjunctivitis (spring catarrh)

  • 1.Palpebral VKC:
  • Difuse papillary hypertrophy, most marked on the superior tarsus
  • Papillae enlarge and have a flat-topped polygonal appearance reminiscent of cobblestone (made of dense fibrous tissue with overlying thickened epithelium giving milky hue, infiltration with eosinophils, lymphocytes, plasma cells, macrophages, basophils)
  • Severe cases: connective tissue septa rupture, giving rise to giant papillae, coated by copious mucus
  • As inflammation settles, the papillae shrink, become more seperated but do not disappear
  • 2. Limbal VKC:
  • Mucoid nodules scattered around the limbus (gelatinous thickening of limbus) with discrete white superficial spots (Horner - Tranta dots)composed predominantly of eosinophils and epithelial debris at the apices of the lesions.
  • 3. Mixed VKC

9. Vernal keratoconjunctivitis (spring catarrh) 10. Vernal keratoconjunctivitis (spring catarrh)

  • Keratopathy :
  • 1. Punctate epithelial erosions : superior cornea
  • 2. Shield ulceration : are sterile ulcers which occur in superior cornea due to cobblestone papillae rubbing on cornea, look like a shield because inferior edge is pointed, may also result from chemical damage to the epithelial surface by mediators released from mast cells and eosinophils, are indolent and may take months to re-epitheliaze, may be complicated by bacterial keratitis, rarely perforation
  • 3. Plaque formation: occurs when the base of the ulcer becomes coated with desiccated mucus results in defective wetting by tears, prevents re-epithelialization, and predisposes to subepithelial scarring and vascularization
  • 4. Pseudogerontoxon : resembles arcus senilis, cupids bow outline in a previously inflammed segment of the limbus.

11. Vernal keratoconjunctivitis (spring catarrh) 12. Vernal keratoconjunctivitis (spring catarrh)

  • Treatment :Purely symptomatic
  • Topical :
  • a. Steroids : mainly for keratopathy, severe discomfort with only conj involvement, 4-6 hourly.
  • - Flourometholone has weaker ocular hypertensive effect than dexamethasone and prednisolone.
  • - treat exacerbations vigorously with high doses, taper to small dose as quickly as possible, discontinue between attacks
  • b. Mast cell stabilizers : Nedocromil 4% BD, Iodoxamide QID, can be used for prolonged periods, not effective in controlling acute exacerbations
  • c. Antihistamines : levocabastine, Olopatadine BD
  • d. Acetylcysteine 0.5% - has mucolytic properties (controls excess mucus), treatment for plaque formation
  • e. Cyclosporine 2% : useful in steroid resistant cases

13. Vernal keratoconjunctivitis (spring catarrh)

  • 2. Supratarsal steroid injection : of betamethasone or triamcinolone for severe disease not responsive to conventional therapy
  • 3. Surgical Treatment : required for severe shield ulcers resistant to medical therapy debridement, supericial keratectomy, excimer laser phototherapeutic keratectomy, amniotic membrane transplantation
  • 4. Others :
  • - Cold compresses : relieves irritation
  • - Tinted glasses to provide comfort
  • - Patient dissuaded from rubbing the eyes as this induces
  • mast cell degranulation with release of histamine

14. Giant papillary conjunctivitis

  • Causes : soft hydrophilic contact lens use, protruding suture ends, ocular prosthesis, after several years of rigid contact lens use
  • Mechanism : types I and IV hypersensitivity reaction
  • Symptoms : itching, watering, foreign body sensation, blurring of vision
  • Signs : conjunctival congestion predominantly in upper palpebral region with large polygonal papillae on suprior tarsal conj.
  • Macropapillae: 0.3 1.0 mm in size
  • Giant papillae : 1 2 mm in size

15. Giant papillary conjunctivitis 16. Giant papillary conjunctivitis

  • Treatment :
  • - discontinue contact lens use
  • - remove offending sutures
  • - cleaning and polishing ocular prosthesis/ replacing one
  • coated with biocoat (biocompatible material)
  • - topical mast cell stabilizers ( cromolyn sodium 6 hourly /
  • olopatadine 12 hourly)
  • - topical antihistamines
  • - decongestants
  • - artificial tears
  • - topical steroids for short terms if needed
  • - subtarsal long -acting steroid injection in severe cases

17. Phlyctenular conjunctivitis

  • Aetiology : non specific delayed hypersensitivity reaction to endogenous bacterial proteins (most commonly tuberculo-protein, staphylococcal, chlamydia) or rarely in mild, long-standing infections of tonsils/adenoids. Many patients also have associated blepharitis
  • Rare today perhaps due to improved hygiene and control of milk infected by bovine tuberculosis
  • Symptoms : discomfort, irritation, reflex lacrimation, pain and photophobia (reflex blepharospasm) if cornea is involved or mucopurulent complication.

18. Phlyctenular conjunctivitis

  • Signs : one or more small (1 mm), round, grey or yellow nodules, slightly raised above the surface, are seen on the bulbar conjunctiva, near the limbus, congestion of the vessels is limited to near the area around the phlyctens.
  • - In later stages : epithelium over the surface becomes necrotic and small ulcers are formed on conj heals rapidly without scar
  • - can be complicated by mucopurulent conjunctivitis
  • - becomes serious when cornea is involved : usually occur near the corneal margin involving only epithelium and superficial layers
  • - corneal phlycten is a grey nodule, slightly raised above the surface, may form yellow ulcer if epithelium breaks down becomes infected usually by staph