Many conditions can cause swelling of the eye, mainly including inflammatory and non-inflammatory factors.
The former is a local cause, mainly due to inflammation of the eyelid or nearby tissues, and can be accompanied by redness, swelling of the eyelid skin, increased local skin temperature and pressure pain, and in severe cases, swollen lymph nodes, chills and fever.
In the latter case, the return of blood or lymphatic fluid is obstructed and manifests as pale, swollen eyelid skin with or without ocular symptoms.