Ординатура / Офтальмология / Английские материалы / Moorfields Manual of Ophthalmology_Jackson_2007

A

B

Fig. 3.6: Thyroid eye disease: axial (A) and coronal (B) CT scans showing marked right inferior rectus and left medial rectus enlargement.

Conservative : ocular lubricants, elevation of head at night, and sunglasses.

Immunosuppression : Consider steroids if active inflammation coexists with: optic neuropathy; sight-threatening exposure keratopathy; significant soft tissue signs; or ocular dysmotility. Start with enteric-coated prednisolone 1 mg/kg/day but reduce dose if less severe. Consider ranitidine 150 mg b.d. p.o. For optic neuropathy review at 1 week and if responding reduce to 20 mg/day over 2–3 weeks and refer for urgent orbital radiotherapy; if not responding, arrange urgent surgical decompression. For marked soft tissue disease or diplopia, reduce from 1 mg/kg/day to 20 mg/day over 2 weeks and review; if responding, refer for nonurgent radiotherapy; if not, consider decompression. Gradually reduce steroids over 1–3

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Thyroid eye disease

months depending on presentation and response. Note baseline tests, side effects, and monitoring required for patients on oral steroids (p. 343). Consider steroid-sparing agents (e.g. azathioprine, ciclosporin) if steroid intolerant or contraindications, and co-manage with physicians. Consider admission and methylprednisolone i.v. for severe sightthreatening disease not responding to oral steroids.

Radiotherapy (XRT) : The evidence base is uncertain, but consider low dose (20–24 Gy) lens-sparing orbital irradiation in cases of sight-threatening disease or significant soft tissue inflammation, including ocular dysmotility. For adjunctive use with immunosuppression, maintain prednisolone at approximately 20 mg/day.

Surgery : Orbital decompression should precede any planned strabismus surgery, which should precede lid surgery.

Orbital decompression should be considered when TED is inactive and stable, unless the sight is threatened. The main indication is facially disfiguring, non-sight-threatening proptosis. Bony decompression for >24 mm proptosis involves three walls (medial and lateral walls, floor) or two and a half walls (only medial half of floor) if <24 mm. Benefit : mean 7–8 mm of globe retroplacement. Risks : visual loss (<1 : 1000), new diplopia ( ≈15%), other risks are low (permanent infraorbital nerve numbness, haemorrhage, infection, late overcorrection or ‘imploding antrum syndrome’, troublesome scar, redo surgery). Fat decompression may be considered, but is less effective and probably associated with an increased risk of restrictive motility disorder.

Strabismus surgery generally involves recessions, once orthoptically stable for ≥ 6 months.

Lid surgery :

Upper lid retraction : retractor recessions are often required and may use a spacer (e.g. auricular cartilage, hard palate mucosa, Alloderm). Consider tarsorrhaphy if this fails.

True lower lid retraction (as opposed to displacement from proptosis): retractor release with spacer.

Cellulitis

Background Preseptal and orbital cellulitis constitute a medical emergency, requiring immediate administration of highdose, broad-spectrum systemic antibiotics before imaging or referral to an orbital specialist. Orbital cellulitis may be lifethreatening if it spreads to the intracranial space. Possible sources of infection include paranasal sinuses, oropharynx, skin, foreign bodies, trauma (including iatrogenic), and haematogenous spread. Bacteria are the commonest cause, especially, streptococci, staphylococci and Haemophilus influenzae. Anaerobes and other Gram-negative organisms are less common. Consider rare causes in immunocompromised patients, especially mucormycosis, aspergillosis, tuberculosis, and viruses, e.g. herpes zoster.

Clinical features Preseptal cellulitis produces fever, pain, swelling, ptosis, tenderness and redness (Fig. 3.7). Orbital cellulitis is similar but with chemosis, reduced eye movements ± diplopia, vision loss, RAPD, and proptosis.

History and examination Ask about sinus disease, trauma, surgery, skin infection, immunocompromise, and diabetes. Perform exophthalmometry, and check temperature, general status (hydration, etc.), eye movements, colour vision, confrontation fields, RAPD, and full ocular examination noting optic disc appearance. Mark the extent of skin inflammation to determine if it is subsequently improving or worsening.

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Cellulitis

Investigations Investigate all cases except mild preseptal cellulitis responding to treatment. Request CT (sinus disease, orbital or intracranial abscess), MRI if suspected organic foreign body, FBC (neutrophilia), blood culture if systemically septic, and blood glucose. Swab any sources of pus for microbiology.

Management Start treatment immediately. Doses given are for adults.

■ Preseptal cellulitis

Mild : Co-amoxiclav 500/125 mg p.o. t.d.s. or flucloxacillin

500 mg p.o. q.d.s., both for 10 days. Review daily until there is a definite improvement, then every 2–7 days until complete resolution. Treat as severe (see below) if the patient fails to respond, or is ≤5 years old, septic, or potentially noncompliant.

Severe : Admit for ceftriaxone 1–2 g i.v. daily in divided doses until responding (1–2 days), then treat as for mild.

■Orbital cellulitis

Admit : Monitor orbital and visual functions 2–3 times daily.

Give ceftriaxone 1–4 g i.v. daily plus flucloxacillin 1–2 g i.v. q.d.s. (beware cholestatic jaundice). In adults (>10 years old) with chronic sinonasal disease add metronidazole 500 mg i.v. t.

d.s. Continue i.v. treatment for 3–5 days, provided condition improves. Request CT, blood glucose, FBC, ± blood culture (if septic). Refer to ENT if sinus disease is detected. Repeat CT to exclude abscess if any deterioration occurs. Arrange urgent neurosurgical referral if there is neurologic deterioration or intracranial abscess. Change to oral antibiotic (see Preseptal cellulitis above) when there is definite improvement. Review every 2–5 days after discharge until complete resolution.

■Orbital abscess

Drain if patient >10 years old or clinical/visual deterioration or failed medical therapy. Consider surgical decompression if the orbit is very tense or not responding to antibiotics. Consider systemic steroids if visual loss occurs despite the above measures.

Idiopathic Orbital

Inflammatory Disease

Background Inflammation is not a diagnosis, but a tissue response to trauma, infection, tumour necrosis, ischaemia, toxins, allergy, etc. Idiopathic orbital inflammatory disease (IOID) is, by definition, a diagnosis of exclusion and in most cases a biopsy is required. Avoid the term ‘pseudotumour’ which implies a diagnosis. Any orbital tissue can be involved and presentation varies from acute to chronic.

Corticosteroids alter both the clinical course and histopathologic findings in a number of inflammatory processes, including IOID, lymphoma, and metastatic carcinoma. Use steroids only after a tissue diagnosis is established, with the following exceptions:

■Superior orbital fissure (Tolosa-Hunt) syndrome,

■Classic orbital myositis,

■Classic thyroid eye disease, or

■Sight-threatening orbital inflammatory disease awaiting urgent biopsy.

Clinical features Inflammation produces:

■Rubor: redness of lids, conjunctiva, and extraocular muscle insertions.

■Dolor: pain on eye movement ± tenderness.

■Calor: warmth.

■Tumor: lid swelling, mass or enlarged lacrimal gland.

■Loss of function: ptosis, diplopia and restricted eye movement, visual loss, sensory loss.

Take a careful general medical history for underlying systemic diseases and arrange full medical examination as required.

Differential diagnoses includes infective cellulitis; haematologic or lymphoproliferative disorders (leukaemia, lymphoma); sinus disease; autoimmune disease, including thyroid eye disease, sarcoidosis and Wegener’s granulomatosis; caroticocavernous fistula; primary or secondary orbital malignancy.

Investigations Arrange orbital CT (or MRI). Consider the following tests: FBC; ESR; CRP; U&E; autoantibodies; sACE; Ca2+; CXR; CT chest.

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Idiopathic orbital inflammatory disease

Management Attempt to determine the underlying aetiology. See the following pages for management of specific inflammatory conditions (dacryoadenitis, p. 89, orbital myositis, p. 90, superior orbital fissure syndrome, p. 91). Consider referral to a physician or oncologist. In the absence of a classic presentation of orbital myositis or superior orbital fissure syndrome, consider NSAIDs, e.g. flurbiprofen 100 mg p.o. t.d.s. for 2 weeks, then 50 mg t.d.s. for 1–2 months; warn of side effects including GI upset and bleeding, and consider prophylaxis with omeprazole 20 mg p.o. daily, or ranitidine 150 mg p.o. b.d. If no response to NSAIDs, arrange orbitotomy (‘opening of the septum’) and biopsy for histopathology ± microbiology. Systemic steroids (typically prednisolone up to 1 mg/kg/day) may be commenced after biopsy. Taper over 1–3 months, monitoring for response. Be aware of steroid side effects and required monitoring (page 343). If inflammation recurs, repeat the biopsy before increasing prednisolone. Low-dose, lens-sparing orbital radiotherapy (20 Gy per orbit) may be considered in refractory cases after a negative biopsy.

Dacryoadenitis

Background Lacrimal gland inflammation is most commonly idiopathic, but may be associated with infection (mostly viral, e.g. mumps, Epstein Barr virus, cytomegalovirus, varicella-zoster), sarcoidosis, Sjögren’s syndrome, and lymphoproliferation. Persistent lacrimal gland inflammation should raise the suspicion of carcinoma.

Clinical features Typically, pain, erythema, swelling ± ptosis of lateral upper lid, and disturbed tear production (Fig. 3.8). Sensory loss or paraesthesiae are rare and if present suspect carcinoma.

Differential diagnosis Consider lacrimal gland carcinoma (p. 98). Consider sarcoidosis if: bilateral; respiratory disturbance; rash; hilar lymphadenopathy on CXR; raised serum Ca2+ and ACE.

Investigations CT for symptoms >2–3 weeks. Biopsy is indicated if there is a poor response after several weeks treatment, >3–4 weeks of pain, or a persistent lacrimal fossa mass at 4 months.

Management Treat as idiopathic orbital inflammatory disease (p. 87)

Follow-up for 6 months then discharge if there is complete resolution and no suspicious features (persistent pain or mass; sensory disturbance).

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Orbital myositis

Orbital Myositis

Background Idiopathic inflammation of the extraocular muscles.

Clinical features Prodrome of periorbital ache exacerbated by eye movement, followed 2–3 days later by diplopia. Symptoms are worst looking away from the field of action of the affected extraocular muscle (EOM). Patients may have proptosis, redness over EOM insertions, upper or lower lid retraction, or ptosis. Repeated attacks may cause fibrosis and a permanent squint.

Investigations CT shows EOM enlargement, classically (but not reliably) involving the insertion (thyroid eye disease classically spares the EOM insertion) (Fig. 3.9).

Differential diagnosis Includes metastasis, vascular malformation, and lymphoproliferative disease. Typically only one EOM is affected; if >2 consider thyroid eye disease (p. 81), which may overlap, as may idiopathic orbital inflammatory disease (p. 87).

Management For classic presentation, prednisolone up to 1 mg/kg/day usually produces a response within 24 hours. Gradually taper over 2–4 weeks. Biopsy if there is a poor response to treatment or recurrence. Radiotherapy is helpful if

cases are recurrent, chronic, or for failed medical treatment with ‘negative’ (i.e. inflammatory change only) biopsy.

Superior Orbital

Fissure Syndrome

(Tolosa-Hunt Syndrome)

Background Idiopathic inflammation involving the superior orbital fissures (SOF) region. May also involve the cavernous sinus.

Clinical features May include retrobulbar ache, ophthalmoplegia, periorbital sensory loss/disturbance (V1 & V2), and visual loss.

Investigations CT shows an infiltrative mass at the orbital apex and loss of the normal fat pad at the SOF (applies to any infiltration at the SOF).

Differential diagnosis Exclude intracranial spread and lymphoma. Trauma may produce similar signs (see page 103), as may tumours and granulomus at the orbital apex.

Management Treat with high-dose prednisolone 1 mg/kg/day if tolerated, tapering according to response. Expect a rapid and good response. Biopsy in recurrent or suspicious cases carries high risk of visual loss, permanent ophthalmoplegia, or sensory loss. Radiotherapy may be appropriate.

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Orbital vascular lesions

Orbital Vascular Lesions

Classification

■Proliferations are usually absent at birth, and result from endothelial proliferation followed sometimes by involution. They are well circumscribed, may cause mass effect, and connect to otherwise normal vascular channels.

■Malformations are present at birth but may be subclinical. They are classified further by their haemodynamics: high flow (arterial/arteriovenous), low flow (venous, a.k.a. ‘varices’) and ‘no flow’ (lymphatic a.k.a. ‘lymphangioma’). These lesions grow commensurately with the patient.

■Shunts are abnormal communications between arterial and venous circulations. They may be congenital (including malformations) or acquired (e.g. traumatic).