When you are presented with a patient with orbital swelling, there are three questions you need to answer:
• What could this be? Is this swelling of something within the orbit (eg, thyroid eye disease)? Is it a bony problem (eg, congenital or trauma)? Could this be a more external soft tissue problem (eg, orbital cellulitis) or even not an orbital problem at all but one adjacent to it that appears to involve it (eg, dacryocystitis)?
• Am I happy to manage this or does it require referral?
• Is there any urgency?
Your assessment should answer these questions and while there are no global referral criteria, there are certainly some pointers that should lower your referral threshold. This article will focus on assessment of these patients. An overview is given of some of the possible causes (follow links for more detail) and a note will be made on referral.
Elicit the following:
• Palpable or visible mass - ask the patient what it is that he or she has noticed. This may be subtle and require them to show/guide you to it.
• Progression: note how and when this all started. Ask how the symptoms have developed over time. Conditions may be acute (eg, infection) or chronic (eg, lacrimal adenoma). Remember to ask about past trauma, however trivial it seemed at the time. Surgical trauma is important to know about too (complications from the anaesthesia can (rarely) cause orbital swellings).
• Proptosis: this refers to the globe protruding (see the separate article on Exophthalmos). It is a common feature in orbital swelling:
o Related to this is how the vision is doing: establish whether the cornea might be compromised by exposure due to proptosis.
o Establish whether there is double vision (diplopia). This suggests that the eyeball is not only protruding but deviating too, either as a result of mechanical pressure of the swelling or involvement of the extraocular muscles.
o Ask specifically about any change in colour perception. Mention of things looking 'washed out' (especially red objects) may be the first warning that the optic nerve is stressed and potentially compromised. This is not a good symptom - see 'Referral', below.
Very rarely, enophthalmos might be misconstrued as orbital swelling if it is subtle.
• Pain: this important symptom may arise from inflammation, infection, acute pressure changes (such as haemorrhage) and bony or neural invasion. It may also be referred from neighbouring structures such as the sinuses in sinusitis.
• Periorbital abnormalities such as sensory change or numbness, redness, tenderness, watering (epiphora) and lid abnormalities (eg, ptosis).
• Past medical history, particularly of sinusitis, thyroid problems (hyperthyroidism and hypothyroidism) and malignancy.
There are several simple tests that can be very useful in assessing these patients in a primary care setting. You will find details of how to perform these tests in the separate article on Examination of the Eye.
• General inspection of the patient. Look at area of trauma or for facial scars, asymmetry, masses, redness, evidence of dysthyroid status, etc. For a rough estimate of any proptosis, look at the patient from above (sit the patient on a chair and stand behind, looking down): note whether it is visible. Note whether the globe appears deviated.
• Assess the optic nerve function of both eyes - this will be important in guiding referral. Check:
o Visual acuity.
o Brightness sensitivity.
o Relative afferent pupillary defect (RAPD).
o Confrontational visual field - perform an assessment.
• Palpate the orbital rim, soft tissues, masses (note location, shape and size).
• Check for a globe pulsation or thrill (with the bell of the stethoscope over the closed eye).
• Check eye movements.
• Examine the globe, front to back, as much as your instruments allow you to.
• The extent of any further periorbital or systemic examination can be guided by your initial findings but consider:
o Skin around the orbit.
o Lid position.
Regional lymph nodes.
o Cranial nerve assessment.
o Any fullness of periorbital regions, nose, etc.
To a certain extent, the number of investigations carried out in a general practice setting are limited in that if the condition warrants imaging, the patient will probably need to be referred, as there is a limit as to what can usefully be done with imaging results. Outlined below are the sorts of investigations that can lead to useful diagnoses but no detail is included of specific findings in specific conditions.
General tests are useful if you are considering infection (FBC, inflammatory markers), malignancy (add liver and renal function tests) or thyroid problems (TFTs). Autoimmune screens are helpful in various inflammatory disorders. Be guided by what you suspect. These tests may be enough to reassure you or, conversely, speed up referral and act as very useful 'starting point' figures as the disease progresses.
Plain X-rays may be useful in suspected fractures (although a blowout fracture is easily missed); however, beyond that, CT remains the first-line imaging modality for orbital disease. Contrast is helpful particularly where malignancy is suspected (but cannot be used in patients with iodine allergy, dehydration, cardiac failure, hyperthyroidism and renal impairment).
MRI scanning tends to be used for diseases at the orbitocranial junction (eg, optic sheath tumours). Ultrasound can be helpful in assessing vascular lesions (using Doppler flow studies) as well as helping to diagnose certain tumours.
In the Eye Unit, patients can be assessed in more detail with regards to their optic nerve function (eg, formal visual field tests), any proptosis (using a painless instrument called an exophthalmometer), ocular motility (with the help of orthoptists) and a more detailed ocular examination, which can be made with the slit lamp.
When considering the causes, work through the surgical sieve as usual. Outlined below are some of the more common or serious causes.
• Dermoid and epidermoid cysts. These are benign collections of normal tissue in an abnormal place. Epidermoid cysts contain keratin, whereas dermoid cysts may include other components of the dermis such as hairs or sebaceous glands. These cysts may have intra-orbital and extra-orbital components with a stalk of tissue connecting them across the bone. Clinically, look for a firm, non-tender, mobile lump, usually seen soon after birth. Deeper lesions may not become evident until adulthood. They require careful, non-urgent excision. CT scanning may be required prior to surgery, to assess their extent fully.
• Dermolipoma. This is the equivalent of a dermoid cyst but it occurs on the ocular surface (typically, the upper outer quadrant). It may present as an irritating lump or with poor cosmesis. Look for a firm, pale, pink-yellow immobile mass on the surface of the globe. It can be surgically excised.
• See the separate article on Eye Trauma.
• Note that apparently trivial injuries with little lacerations may lead to lid swelling and an infection associated with a retained foreign body.
• See the separate article on Orbital and Preseptal Cellulitis (this includes details on the less serious condition of preseptal cellulitis).
• 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.
Disorders of soft tissues and extraocular muscles
• Graves' disease. See the separate article on Thyroid Eye Disease.
• Orbital myositis. This is an idiopathic inflammation of the extraocular muscles, characterised by a periorbital ache exacerbated by eye movement, followed 2-3 days later by diplopia. There may be associated proptosis, redness over the area of muscle insertion on the globe and lid malposition. Classic cases are treated with prednisolone but if there is doubt or a poor response to treatment, a biopsy may be required to exclude other diagnoses such as metastases or lymphoproliferative disease.
These may include:
• Orbital vasculitis
• Sjögren's syndrome
• Wegener's granulomatosis
• Systemic lupus erythematosus
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, arteriovenous fistulae and venous varices.
• Carotico-cavernous fistula:
o This occurs when the arterial circulation connects with the venous circulation in the cavernous sinus.
o Causes include blunt head trauma (80% of cases), post-surgery (eg, septorhinoplasty), carotid aneurysm rupture with reflux of blood into the cavernous sinus or it can occur spontaneously (especially in hypertensive patients).
o There is engorgement of the eye vessels with lid and conjunctival oedema. Vision may be blurred.
o Look for a (usually unilateral) proptosis, severe conjunctival oedema (chemosis) and limited eye movement caused by a combination of cranial nerve palsy and physical limitation of movement. Also note an exophthalmos which may be pulsatile, with a loud bruit over the eye and sometimes tinnitus.
o These patients need to be admitted for an urgent ophthalmological review, ultrasound and CT/MRI.
o Some fistulae (particularly indirect ones) may close spontaneously but conservative management includes protection of the cornea with lubricants. Any associated rise in intraocular pressure will be treated with ocular hypotensives.
o Treatment of choice for a symptomatic carotico-cavernous fistula is intervention radiology using a balloon catheter via the femoral artery. Direct surgery via the superior ophthalmic vein may be required for embolisation.
o Rarely, severely refractory fistulae require surgical or endovascular occlusion of the internal carotid artery.
• Orbital varices. These are irregular venous dilatations which enlarge during Valsalva's manoeuvre. They may ache or cause pain and proptosis if they bleed. If they get too problematic, they can be operated on but there is a risk of postoperative bleeding and recurrence.
• Haemangiomas. These develop in the first months of life and then gradually resolve (the vast majority by 10 years of age. Superficial dermal ones are 'strawberry naevi' and account for 90% of lesions. Although they are benign, large ones may secondarily cause ptosis or astigmatism, both of which can lead to amblyopia or ocular motility problems. Very large lesions may be associated with red blood cell or platelet sequestration and circulatory problems. Such large or problematic lesions must be carefully monitored and may need treatment with intralesional corticosteroids ± excision (although there is a risk of haemorrhage).
• Orbital wall infarction. This is a rare but serious cause of lid swelling associated with restricted ocular movement. A possible cause is the vaso-occlusive crises brought about by sickle cell disease.
See the separate article on Eye and Optic Nerve Tumours. Other relevant separate articles include Retinoblastoma and Rhabdomyosarcoma.
Other tumours occurring in the orbit include:
• Lacrimal adenomas. Locally invasive tumours of the lacrimal gland. These occur in middle age and slightly more often in males. There is gradual, painless proptosis over months or years with a palpable tumour in the superior temporal quadrant of the orbit. Treatment is excision of the tumour and the lacrimal gland, with an excellent prognosis if the removal is complete. Malignant transformation occurs in 10% of tumours over 10 years.
• Lacrimal carcinoma. A rare malignant tumour of the lacrimal gland, usually occurring in middle age or elderly people. They grow rapidly, causing more rapid proptosis than adenomas, associated with ophthalmoplegia due to perineural spread, and pain. If diagnosed early, surgical removal may be attempted (usually followed by radiotherapy) but the prognosis is very poor.
• Neuroblastoma. This is one of the most common of childhood malignancies. It arises from the primitive neuroblasts of the sympathetic chain, most commonly in the abdomen. Orbital metastases may be unilateral/bilateral and usually present with abrupt proptosis associated with a superior orbital mass. Prognosis is very poor.
o In children the orbit may be the site of secondary deposits from neuroblastoma or acute leukaemia.
o In adults, breast or lung carcinoma may give secondary deposits in the orbit.
• Lymphomas (eg, Burkitt's lymphoma). These may form orbital deposits (therefore, examine the liver, spleen and lymph nodes, and check FBC).
• Nasopharyngeal tumours and mucoceles and pyoceles of the ethmoid and frontal sinuses. These occasionally invade the orbit. A frontal mucocele 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. Maxillary carcinoma, ethmoidal carcinoma and nasopharyngeal carcinoma may invade the orbit. See the separate article on Pharyngeal Cancer.
Idiopathic orbital inflammatory disease
This condition, previously known as 'orbital pseudotumour', is not a diagnosis but rather the description of an inflammatory response in the orbit, in response to trauma, infection, tissue necrosis, ischaemia, toxins and so on. It is a diagnosis of exclusion which can involve any of the orbital tissues. Its cause is not known.
• It can affect one or both eyes of relatively young patients (less than 50 years old).
• Inflammation may be diffuse, anterior, apical, around the optic nerve or selectively affecting the lacrimal gland.
• Typically it 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.
• A full blood screen is done to look for evidence of infection, inflammation or autoimmune disease.
• Ultrasound and CT scans typically show an infiltration of the orbit, and an inflammation of the sclera and optic nerve.
• Any underlying cause should be managed and the inflammation itself may respond to non-steroidal anti-inflammatory drugs. Failure to respond may prompt a diagnostic biopsy ± systemic steroids. Refractory cases may also be treated with radiotherapy.