What is typically seen on exam in preseptal cellulitis that distinguishes it from orbital cellulitis?

Preseptal cellulitis, an infection of the eyelid and periorbital tissues, primarily results in localized swelling and inflammation of the eyelid without directly affecting the underlying structures of the orbit. One of the hallmark clinical findings that helps to distinguish preseptal cellulitis from orbital cellulitis is the swelling of the eyelid. In preseptal cellulitis, this swelling can be pronounced, while signs of more severe involvement, such as those seen in orbital cellulitis, might manifest as pain with ocular movement, visual changes, or potentially altered ocular discharge.

The eyelid swelling in preseptal cellulitis is usually unilateral and localized to the eyelid, sparing the eye itself from the more serious complications associated with orbital involvement. This difference in presentation is crucial for clinicians as it informs the appropriate treatment and management strategies. Understanding these distinctions aids in ensuring timely and proper interventions to prevent progression to more severe conditions, such as orbital cellulitis, which can lead to serious complications including vision loss.