Periorbital cellulitis (not to be confused with orbital cellulitis, which is posterior to the orbital septum), is an inflammation and infection of the eyelid and portions of skin around the eye anterior to the orbital septum. It may be caused by breaks in the skin around the eye, and subsequent spread to the eyelid; infection of the sinuses around the nose (sinusitis); or from spread of an infection elsewhere through the blood. [Source: Wikipedia 
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