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Orbital Cellulitis


Richard C. Allen

, MD, PhD, University of Texas at Austin Dell Medical School

Reviewed/Revised Oct 2022
Topic Resources

Orbital cellulitis is infection affecting the tissue within the orbit and around and behind the eye.

  • Infection can spread to the orbit from sources such as the sinuses around the nose.

  • Symptoms include pain, swelling, red eye, fever, a bulging eye, impaired vision, and impaired eye movements.

  • Usually, computed tomography or magnetic resonance imaging of the orbits is done.

  • Antibiotics are given by vein and the person is admitted to the hospital.

Both orbital cellulitis and preseptal cellulitis Preseptal Cellulitis Preseptal cellulitis is infection of the eyelid and of the skin and tissues around the front of the eye. (See also Introduction to Eye Socket Disorders.) Both preseptal cellulitis and orbital... read more Preseptal Cellulitis are more common among children. Preseptal cellulitis is far more common than orbital cellulitis. However, orbital cellulitis is more dangerous.

Orbital cellulitis usually is caused by spread of an infection to the orbit from the sinuses around the nose (nasal sinuses) but can also be spread from infection of the teeth or bloodstream. An animal or insect bite or another wound to the eyelids can also spread infection and lead to orbital cellulitis. A foreign body in the orbit, particularly if organic (for example, wood), can also cause orbital cellulitis.

Without adequate treatment, orbital cellulitis can lead to blindness as well as to severe illness. Infection can spread to the brain (meningitis Meningitis ) and spinal cord. Blood clots can form and spread from the veins around the eye to involve a large vein at the base of the brain (the cavernous sinus) and result in a serious disorder called cavernous sinus thrombosis Cavernous Sinus Thrombosis Cavernous sinus thrombosis is a very rare disorder in which a blood clot (thrombosis) forms in the cavernous sinus (a large vein at the base of the skull). Cavernous sinus thrombosis is usually... read more .

Symptoms of Orbital Cellulitis

Diagnosis of Orbital Cellulitis

  • Computed tomography or magnetic resonance imaging

  • Cultures of blood and samples from nasal sinus

Often, doctors obtain samples from the nasal sinuses as well as blood samples and send them to a laboratory for testing. The samples are cultured Diagnosis of Infectious Disease Infectious diseases are caused by microorganisms, such as bacteria, viruses, fungi, and parasites. Doctors suspect an infection based on the person's symptoms, physical examination results,... read more (to grow microorganisms) to determine what bacteria are causing the infection, which areas are infected, and which antibiotic should be used. A person with orbital cellulitis undergoes a more detailed examination by an ophthalmologist (a medical doctor who specializes in eye disorders).

Treatment of Orbital Cellulitis

  • Antibiotics

  • Surgery

People with orbital cellulitis are typically admitted to the hospital. Antibiotics are started as soon as possible, before the results of the laboratory testing are known. Antibiotics are given by vein. The antibiotic used at first may be changed if the culture results suggest that another antibiotic would be more effective. Sometimes surgery is needed if vision is impaired, to drain a collection of pus (abscess) or an infected nasal sinus, to remove a foreign body, or to help treat the infection if antibiotics alone are not effective.

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