Orbital cellulitis is the inflammation of eye tissues behind the orbital septum. It most commonly refers to an acute spread of infection in the eye socket from either the adjacent sinuses or through blood.
It is a major infection of the eye. It involves the soft tissues of the eye socket (such as the eyeball, muscles, fascia etc) posterior to the orbital septum (eyelids). This is different from the pre-septal cellulitis, which affects the soft tissues of the eyelids, although both conditions could occur at the same time.
It can affect both children and adults. However, it is more common among children, affecting twice as many boys as opposed to girls. There is an increased incidence of the disease during the rainy season due to increased risks of respiratory infections associated with the weather.
Orbital cellulitis is usually caused by three main processes.
Irrespective of the cause, orbital cellulitis may be associated with very serious complications, such as blindness, glaucoma, optic neuritis etc. It could even spread to the brain and cause meningitis. Therefore, prompt identification of its symptoms is essential.
Orbital cellulitis usually presents with swelling, warmth, pain in the eye with movement and reduced eye movement. They are usually unable to open the eye and if they can, they have double vision. There is bulging out of the eye beyond its margin, redness of the eye and eyelids with fever. In some patients, there is usually a preceding history of sinusitis or respiratory tract infection that helps to point to the cause.
Once orbital cellulitis is suspected, prompt admission to the hospital is mandatory for extensive evaluation. As infants and young children are prone to resist, patients and caregivers are advised not to forcefully try to open the affected eye to examine or to attempt to put medication or any concoction as it could traumatise the eye further and worsen the condition.
Physical examination usually reveals a marked swelling and bulging of the eye (proptosis) with conjunctival cheilosis (the eye looks wet and gelatinous). There is pain and tenderness of the surrounding orbit and in young children, this could make examination difficult. Vision could also be affected.
Although diagnosing orbital cellulitis can be achieved clinically, investigations are essential to determining the cause and extent of the infection/inflammation. Nasal sinus and eye swabs are done and sent to the lab for testing to reveal the offending agent. A blood culture and a complete blood count could also be done. Although they rarely yield any sign of the offending agent but may show signs of systemic involvement. It is advisable to take the lab specimen before commencing empirical antibiotics. An MRI or CT scan should be done to determine the extent of the infection and if surgical intervention would be required.
The mainstay of treatment involves the use of intravenous antibiotics, of which most patients respond adequately. The antibiotic regimen is targeted at pathogens most commonly implicated in sinusitis, such as strepPneumonia,staph aureus or non-typeable H. Influenza. This involves using a second or third generation cephalosporin for 14 days, followed by two or three weeks of oral antibiotics. If the orbital cellulitis is due to direct trauma, broad-spectrum antibiotics should be considered with good gram positive and negative coverage and it should be taken till there are clear signs of improvement.
Surgical intervention is necessitated if there is a failure to respond to the appropriate antibiotics after 24 to 48 hours of administration.
Orbital cellulitis is a largely underestimated condition that if not properly managed could compromise the health and wellbeing of your child. Vigilance and early identification of its key features so that prompt management is commenced cannot be overemphasised