Orbital Swellings

Lesions in the bony orbit typically present with proptosis (synonym exophthalmos) which means protrusion of orbital contents. There may be deviation of the eyeball with or without diplopia. Orbital pain usually arises from neighbouring structures (e.g. sinusitis). Conditions may be acute (e.g. infection) or chronic (e.g. lacrimal adenoma) and may affect any one of the structures within the orbit.

Depends on underlying cause but may include:

• Proptosis: protrusion of the eye out of the orbit due to a space occupying lesion in the orbit.
• Eye pain, which is often worse with eye movement.
• Diplopia occurs as a result of muscles being affected and is therefore associated with limitation of movement of the eye.
• Visual acuity: affected when the nerve is involved, when the macula is distorted (e.g. posterior space occupying lesion) or when there is an exposure keratopathy due to a proptosis of the eye.

Trauma

• Apparently trivial injuries with little lacerations may lead to lid swelling and an infection associated with a retained foreign body.

Infective

• Orbital cellulitis:
  • Preseptal cellulitis also presents with orbital swelling but is much less serious than orbital cellulitis. Preseptal cellulitis is discussed in the article on Orbital Cellulitis.
  • Orbital cellulitis usually results from spread of infection from adjacent structures, e.g. sinuses, eyelid or teeth. May also result from trauma.
  • Most often occurs in children.
  • Presents with with sudden onset of swollen eyelids and proptosis, fever and reduced eye mobility.
  • Causes of infection include Staphylococci and Streptococci.
  • Urgent admission and intravenous antibiotics are required.
  • The infection may extend to the meninges and cavernous sinus.
  • Treatment of orbital cellulitis is with systemic antibiotics.
  • Cavernous sinus thrombosis may occur as a complication of orbital cellulitis and presents with bilateral proptosis, venous engorgement and total paralysis of ocular movements.
  • Blindness may occur following orbital cellulitis, because of pressure on the optic nerve or thrombosis of the optic vessels vessels.^1,2
• Hydatid cyst:
  • In parts of Africa, particularly northern Kenya, hydatid disease is common, and it may cause proptosis.
  • Very careful surgical excision can be performed, but it is important not to rupture the cyst.

Thyroid eye disease

• Eye disease due to hyperthyroidism usually causes bilateral but sometimes unilateral proptosis. It is more common in middle-aged women.
• Besides signs of thyroid dysfunction there may be lid retraction and limitation of ocular movements.
• If the patient is thyrotoxic, this should be treated.
• If the proptosis threatens vision then systemic steroids may be used and, if this fails, an operation to decompress the orbit can be performed.

Inflammatory disorders

• Sarcoidosis, ocular myositis, scleritis, orbital vasculitis, Sjogren's disease, and Wegener's granulomatosis.

Vascular disorders

• Carotico-cavernous fistula:
  • Vascular abnormalities of the orbit may be present at birth, develop during childhood or appear for the first time in adults. They include cavernous and capillary haemangiomas, arterio-venous fistulae and venous varices.
  • Carotico-cavernous fistula are usually due to carotid aneurysm rupture with reflux of blood into the cavernous sinus.
  • May be spontaneous or due to trauma or post-septorhinoplasty. There is engorgement of the eye vessels with lid and conjunctival oedema.
  • Exophthalmos may be pulsatile, with a loud bruit over the eye and sometimes tinnitus.
  • Some fistulae may close spontaneously but conservative management includes protection of the cornea with lubricants.
  • Treatment of choice for a symptomatic carotico-cavernous fistulas is intervention radiology using a balloon catheter via the femoral artery. Direct surgery via the superior ophthalmic vein may be required for embolisation.
  • Rarely, severely refractory fistulas require surgical or endovascular occlusion of the internal carotid artery.
• Orbital varices
• Haemangiomas

Orbital tumours

• Primary neoplasms are rare but include angioma, dermoids, meningioma or glioma of the optic nerve, and lacrimal adenoma or carcinoma.
• Retinoblastomas:
  • Retinoblastomas are malignant tumours of the retina which may be familial and may be bilateral. They occur most often in infants and young children.
  • The first sign can be a squint, followed by a white/yellow reflex in the pupil. Early enucleation of the eye or radiotherapy may save the child's life.
  • If left untreated, the tumour spreads along the optic nerve causing proptosis. The prognosis at this stage is very poor.
• Meningiomas:
  • Benign, slowly growing tumours which may affect the sphenoid bone or the optic nerve.
  • There is gradual proptosis, paralysis of eye movements and loss of vision.
  • Diagnosis can usually be made on the x-ray showing sclerotic appearances.
  • There is no effective treatment.
• Optic gliomas: slow growing benign tumours of the optic nerve. There is loss of vision with optic atrophy and then unilateral proptosis. Treatment is usually not indicated.
• Lacrimal adenomas: benign but locally invasive tumours of the lacrimal gland. There is gradual proptosis over months or years with a palpable tumour in the superior-temporal quadrant of the orbit. Treatment is total excision of the tumour and the lacrimal gland.
• Lacrimal carcinoma: rare malignant tumour of the lacrimal gland usually occurring in elderly people. If diagnosed early surgical removal may be attempted, but the prognosis is poor.
• Rhabdomyosarcoma:
  • Malignant sarcoma
  • Most often occurs in childhood and most often affects head and neck
• Metastases:
  • In children the orbit may be the site of secondary deposits from neuroblastoma or acute leukaemia.
  • In adults breast or lung carcinoma may give secondary deposits in the orbit.
• Lymphomas, e.g. Burkitt's lymphoma, may form orbital deposits (therefore examine the liver, spleen and lymph nodes, and check full blood count).
• Neuroblastoma: in children unilateral proptosis may be the first sign of a neuroblastoma.
• Nasopharyngeal tumours and mucocoeles and pyocoeles of the ethmoid and frontal sinuses occasionally invade the orbit. A frontal mucocoele is a cystic swelling originating from the frontal sinus. There is slowly progressive proptosis with a palpable tumour in the superior-nasal quadrant of the orbit. Treatment is by surgical drainage.
• Benign tumours, e.g. dermoid cyst.

Orbital pseudotumour

• Condition of unknown cause which can affect one or both eyes of relatively young patients (less than 50 years old).
• Also called idiopathic orbital inflammation.³
• Inflammation may be diffuse, anterior, apical, around the optic nerve or selectively affecting the lacrimal gland.
• Typically presents with the rapid development of pain, unilateral or bilateral proptosis with or without paralysis of the extra-ocular muscles, and swelling around the eye and orbit.
• The ESR may be raised.
• Ultrasound and CT scans typically shows an infiltration of the orbit, and an inflammation of the sclera and optic nerve.
• The condition responds to high dose systemic steroids which can be tailed off over 4 weeks, although a maintenance dose of prednisolone 5 mg/day may be required for 3-6 months.