Ординатура / Офтальмология / Английские материалы / Moorfields Manual of Ophthalmology_Jackson_2007

Ocular Mucous

Membrane Pemphigoid

Background Ocular mucous membrane pemphigoid (OcMMP) is a type II hypersensitivity disease with antibodies to basement membrane and subsequent conjunctival scarring. There is a female preponderance with typical onset age 60–70 years. Previously termed ocular cicatricial pemphigoid.

History A chronic red eye is often misdiagnosed as infectious conjunctivitis. Ask about topical medications associated with OcMMP including pilocarpine, epinephrine, timolol, ecothiaphate iodine, and antivirals. There may be mucosal lesions of the nose, mouth, pharynx, trachea, oesophagus, anus, urethra, and vagina. If dysphasia and dyspnoea are present refer to an ENT specialist for endoscopic examination.

Examination

■Stage 1: chronic conjunctivitis with mild conjunctival and corneal epitheliopathy. Look for subtle subepithelial conjunctival fibrosis with a meshwork of fine white striae over the tarsus. The earliest sign is often a loss of the plica semilunaris as a result of subtle scarring.

■Stage 2: shortening of the fornices with abnormal surface wetting. Corneal keratinization may occur.

■Stage 3: Symblephara (Fig. 4.4, p. 112). Cicatrization deforms the lash follicles, lacrimal and meibomian gland ductules, with resultant aqueous and oil deficiencies, and also results in trichiasis due to cicatricial entropion. Mucin deficiency may exacerbate dry eye.

■Stage 4: ankyloblepharon, corneal keratinization, and totally dry eye.

Investigations Biopsy conjunctival and buccal mucosa for direct immunofluorescence. If skin lesions are present arrange a dermatology consultation and perilesional skin biopsy. Use specialist histology services, e.g. St John’s Dermatology Unit, St Thomas’ Hospital, London SE1 7EH; Tel: 020 7188 7188. False negatives are common in ocular disease (only 60–80% are positive) although not in buccal or skin disease. A positive biopsy or indirect immunofluorescence is not mandatory before treatment of typical disease.

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Ocular mucous membrane pemphigoid

Treatment This requires specialized knowledge. For mild to moderate disease use dapsone at an initial dose of 25 mg b.d., increasing up to 150 mg per day as required. Contraindications include sulfa allergy and glucose-6-phosphate dehydrogenase deficiency; anaemia is common. Sulfasalazine, an alternative sulfonamide, may be better tolerated at 1–2 g orally daily. If the response is incomplete, add methotrexate 7.5–15 mg p.o. weekly, azathioprine 2–3 mg/kg p.o. o.d., or mycophenolate 1 g b.d. If there is no response to a sulfonamide then discontinue this and use methotrexate, azathioprine, or mycophenolate alone. For severe disease or moderate disease unresponsive to these drugs use prednisolone 1 mg/kg/day p.o. with cyclophosphamide 1–2 mg/kg/ day and taper off steroids once the inflammation is controlled; usually in 2–4 months. All these drugs require mandatory screening for side effects. Ciclosporin is not effective.

Local treatment is important. Remove any lashes abrading the cornea. Remove small numbers of lashes with electrolysis: for larger areas use a lid split and cryotherapy but beware reactivation of inflammation. Treat tear film deficiencies with punctal occlusion and preservative-free tear substitutes. Optimize meibomian gland function with warm compresses and lid massage. Bandage contact lenses may be used with caution. Keratinized tarsal conjunctiva may respond to topical retinoids. Oculoplastic surgery may be necessary to treat any lagophthalmos or reconstruct the fornices. Conjunctival or corneal surgery can trigger reactivation and patients should be effectively immunosupressed beforehand. Epithelial defects may fail to heal after surgery. Keratoprostheses are sometimes required.

Follow-up About 20% of patients have mild disease and can be reviewed annually to assess progression or more frequently if ongoing local therapy is require for surface disease. Patients on systemic drugs require blood tests to screen for toxicity, initially weekly. These can often be undertaken via the general practitioner, with 2–3 monthly ophthalmology review of treatment effect.

Subconjunctival Haemorrhage

History Most cases are idiopathic but ask about hypertension, Valsalva (coughing/constipation/heavy lifting), bleeding diathasis, anticoagulants, and trauma.

Examination Fresh haemorrhage appears as a bright red area, often over a large area (Fig. 4.18). Haemorrhage without a posterior margin may be associated with an intracranial bleed. Check BP and IOP.

Investigations Request coagulation screen and FBC only if recurrent.

Treatment None required. Reassure patients that the haemorrhage will fade over 2 weeks.

Follow-up Discharge with referral to a haematologist if a bleeding diathasis is detected, or general practitioner if hypertensive. Otherwise, no follow-up is required.

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Superior limbic keratoconjunctivitis

Superior Limbic

Keratoconjunctivitis

Background A rare inflammatory conjunctivitis that tends to affect middle-aged women.

History Patients typically describe remissions and exacerbations of burning, foreign body sensation, mild photophobia, mucoid discharge, and tearing. Ask about contact lens wear, ocular surgery, and symptoms of thyroid dysfunction.

Examination Signs are usually bilateral but asymmetrical, and less severe than symptoms. Look for papillae (evert lids), conjunctival hyperaemia and thickening, most intense at the superior limbus, and fading towards the fornix, ± conjunctival keratinization. There is superior, superficial punctate keratitis (best seen with rose bengal) (Fig. 4.19) and micropannus, with filamentary keratopathy in 33% of cases. Tear deficiency may be present.

Investigations Thyroid function tests (50% have associated thyroid dysfunction).

Treatment Treat any thyroid dysfunction. G. acetyl cysteine 5% q.d.s. reduces filaments. Offer tear substitutes as required. Bandage contact lenses may help. In severe cases consider surgical resection of the superior limbal conjunctiva. Courses of topical corticosteroids can be useful for treatment of severe disease. The disease often remits after 2–4 years

Miscellaneous Conditions of

the Conjunctiva

Pingueculum A yellowish raised area of bulbar conjunctiva in the palpebral aperture along the horizontal meridian (Fig. 4.20). May gradually thicken or become inflamed but often asymptomatic, and only noticed when the background conjunctiva becomes red, e.g. conjunctivitis. No treatment is usually required but if the area becomes inflamed consider topical lubricants or weak topical steroid, e.g. G. fluoromethalone (FML) t.d.s. reducing over 3 weeks. Excision biopsy is occasionally needed for symptomatic relief.

Oncocytoma (oxyphilic adenoma) Rare, 2–5 mm cystic yellow-tan caruncular mass presenting in older patients. Usually asymptomatic. May occur in the lacrimal gland, conjunctiva, and extraocular sites. No treatment is required for caruncular lesions but they can be excised if cosmetically embarrassing. Extracarunclar lesions may become malignant.

Kawasaki disease A rare condition occurring most commonly in girls aged 2 months to 9 years. Carries a 1–2% mortality rate. Produces conjunctivitis that does not require treatment, but this may be the presenting feature of the disease and hence requires urgent paediatric referral for management of extraocular features. These include cervical lymphadenopathy, dry

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Miscellaneous conditions of the conjunctiva

lips, ‘strawberry’ tongue, arthralgia, arthritis, palmar erythema, and desquamation of fingertip skin.

Oculoglandular syndrome Also called cat-scratch fever and Parinaud’s conjunctivits. Caused by a reaction to a cat scratch or more rarely pathogens such as M. tuberculosis, T. pallidum, and C. trachomatis. Produces grossly visible preauricular lymphadenopathy, low-grade fever, and unilateral conjunctival granulomata with focal necrosis ± ulceration. Consider cat-scratch disease skin test ± conjunctival biopsy. Resolves spontaneously over 2–3 months. Excision of solitary granulomata may be curative. A course of oral tetracyclines speeds resolution of catscratch disease.

Chemical Injury

Background Compounds include alkalis, acids, solvents, and detergents. Alkalis penetrate ocular tissue and are the most harmful, e.g. ammonia, lye in drain cleaner, caustic potash, Mg(OH)2 from ‘sparklers’, lime in wet plaster, cement, and mortar. Acids usually produce more superficial damage but concentrated acids may produce effects that are indistinguishable from alkali injury.

Treat as an emergency, even before vision testing.

Immediate treatment Measure the pH of both eyes (normal: 7.3–7.6). Instil topical anaesthetic and eyelid speculum and irrigate the eye(s) copiously with saline or Ringer’s lactate solution delivered via i.v. tubing for at least 30 minutes. Avoid acidic solutions to neutralize alkalis or vice versa. Pull down the lower lid and double-evert the upper lid to irrigate the fornices and remove any particulate matter. This may rarely require a general anaesthetic. Five minutes after ceasing irrigation, retest the pH. Continue irrigating until neutral. Persistently elevated pH suggests retained material.

History Document the chemical, time, nature of exposure, and any first aid measures. If available, examine the chemical container labels and test its pH. Contact a poisons centre for more information if required (p. 710).

Examination Record VA, facial injuries, and IOP. Apply fluorescein and systematically note:

■Lids: may be burned or oedematous.

■Conjunctiva: extent of epithelial loss, chemosis, and haemorrhage. Grade any limbal ischaemia:

I = little or none.

II = < 50% of the limbus (Fig. 4.21).

III = 50–100% limbal ischaemia, but proximal conjunctiva preserved.

IV = 50–100% limbal ischaemia and loss of proximal conjunctiva. Severe ischaemia may produce a deceptively white eye.

■Cornea: clarity, size and depth of any defects. Total epithelial defects may be easy to miss. Bowman’s layer is slow to take up fluorescein compared with the stroma and basement membrane.

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grade II. Grade III and IV epithelial defects persist. The degree of ischaemia may initially be underor overestimated so reassess. Continue ascorbate and citrate until the epithelium has healed. Taper off corticosteroids to promote repair, replacing with progestational steroids (e.g. medroxyprogesterone 1% from i.v. preparation 4–6 times daily) or NSAIDs (e.g. G. diclofenac 0.1% t.d.s). Once the epithelium has closed, topical corticosteroid may be restarted if necessary. Doxycyclin 100 mg o.d. p.o. may be useful for its anticollaginase activity.

3.Late repair phase (from day 21) Grade II injuries may heal with conjunctival epithelium in the ischaemic sector. Grade III injuries may also re-epithelialize from the conjunctiva with associated superficial and deep stromal vascularization, persistence of goblet cells in the epithelium, and poor epithelial basement membrane adhesion. Grade IV injuries fail to re-epithelialize and require surgical intervention. In more severe chemical injuries corneal inflammation, collagen synthesis, and collagenase activity peak at this time. Continue treatment to minimize inflammation and collagenase activity. Correct any tear deficiency.

Surgical interventions An amniotic membrane patch sutured over the entire ocular surface, and secured to the skin and fornices, may aid healing in severe disease unresponsive to conservative measures in 10–14 days. Tissue glue is useful for impending or small (<1 mm) perforations (p. 156). Tectonic keratoplasty may be required for larger perforations. The success of future surgical interventions, e.g. penetrating keratoplasty, is dependent upon an adequate tear film and the population of limbal stem cells. These may be harvested from the contralateral eye in uniocular injuries, or as an allograft. Keratoprosthesis may be required for severe bilateral chemical injuries.

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Optometry and general practice guidelines

Optometry and General

Practice Guidelines

General comments

The commonest external eye disease seen in primary care is conjunctivitis. The symptoms, pattern of redness, and type of discharge usually suggests the diagnosis. Diffuse conjunctival injection is typical, whereas perilimbal injection, intraocular pain, and photophobia suggest uveitis or corneal disease. Ask about contact with conjunctivitis. Purulent discharge and surface irritation is typical of bacterial infection. A watery discharge and systemic viral features suggests viral conjunctivitis. A personal or family history of atopy and ocular itch suggest allergic conjunctivitis. There is no specific treatment for adenoviral conjunctivitis but it spontaneously resolves in 2–3 weeks. Provide appropriate advice about cross-infection and offer topical hypromellose q.d.s. p.r.n. It is commonplace to prescribe antibiotics (e.g. G. chloramphenicol q.d.s.) for presumed bacterial conjunctivitis although it will often resolve without treatment. Avoid protracted (>7 days) antibiotics that commonly cause drop hypersensitivity (look for periocular skin redness, papillae, and itch.). Treat allergic conjunctivitis by mast cell stabilizers, e.g. G. nedocromil sodium b.d. for 1 month, and consider antigen avoidance (avoid house pets if possible and maintain a hypoallergenic bedroom and domestic environment as

for asthma protocols). Most cases of conjunctivitis can be treated in primary care. Swabs are not necessary for typical cases but send viral, bacterial, and chlamydial swabs if there is no improvement in 5 days. Refer if there is no improvements in 2 weeks or if the vision changes at any time. The commonest findings on referral are adenoviral conjunctivitis, blepharitis, drop hypersensitivity, and dry eye.

General practice

Do not prescribe steroid eyedrops without specialist review. A single episode of subconjunctival haemorrhage does not routinely require investigation or referral but ask about bleeding/bruising/ anticoagulants and check BP. Refer unexplained, recurrent subconjunctival haemorrhage.