Orbital Cellulitis (Eye Socket Infection)

What is an orbital cellulitis?

The eye socket, or orbit, is made up of the bones and tissue that surround the eye. A layer of tissue called the orbital septum separates the contents of the eye socket from the eyelids. If an infection spreads behind the orbital septum it is called orbital cellulitis.

How does it occur?

Orbital cellulitis can occur in several ways:

• From a sinus infection. The infection can spread from the sinuses into the orbit through the thin bones that separate the eye socket from the sinuses. This is the most common cause.
• From the spread of infection of the skin around the eye and eyelids (preseptal cellulitis).
• From injury or surgery that allows bacteria into the eye socket.
• Rarely, from an infection that starts somewhere else in the body and spreads through the bloodstream.

Orbital cellulitis is usually caused by bacteria. Most commonly, they are the same bacteria that cause sinus infections. However, people with diabetes, people receiving chemotherapy and people with HIV or other problems with their immune system may have orbital cellulitis caused by fungus.

What are the symptoms?

Symptoms of orbital cellulitis include:

• decreased vision
• double vision
• pain in and around the eye
• discharge
• fever

You may have sinus symptoms, such as runny nose and congestion before or during the same time as these symptoms.

Signs of orbital cellulitis include:

• swelling and redness of the eyelids and soft tissue around the eye
• swelling of the lining of the eyeball (called conjunctival chemosis)
• problems moving the eye in one or more directions
• the eye may appear to bulge forward compared to the other eye (called proptosis)
• increased pressure in the eye

How is it diagnosed?

Your healthcare provider will ask about your symptoms, do a physical exam, and perform tests. Tests you may have are:

• an exam using a special microscope (a slit lamp) to look closely at your eye
• an exam with drops and special lenses to look into the back of your eye (a dilated exam)
• measurements to look at the position of the affected eye compared with the normal eye
• an imaging scan to look at the bones and tissues of the eye socket and the sinuses (either a computed tomography/CT scan or with a magnetic resonance imaging/MRI scan)
• cultures of discharge from the eye
• blood tests to check for an elevated white blood cell count (a sign of infection) and to check for bacteria in the blood.

How is it treated?

Orbital cellulitis is an emergency that can cause permanent blindness if not treated immediately. When it is diagnosed, you may be admitted to the hospital and started on intravenous antibiotics (antibiotics given through a vein). Based on the results of your exam and your CT scan or MRI, your healthcare provider may recommend surgery to drain the infection from your eye socket and sinuses.

How long will the effects last?

If the infection is found and treated quickly, you may have no permanent effects from orbital cellulitis. Loss of vision can result from pressure on the optic nerve or from problems with blood flow to the eye. This can be permanent.

How can I prevent orbital cellulitis?

If you develop an infection of the skin around the eye or of the eyelids you should contact your healthcare provider right away. If you have a history of sinus infections and develop any of the above symptoms, you should also seek immediate medical attention.