Contributor. Gordon K. Klintworth
Edema results from any disorder that causes an imbalance between with the perfusion pressures and osmotic pressures that interfer with the normal transit of fluid to and from the circulation. Edema may be localized or generalized. Within the ocular tissues edema may affect several specific parts of the eye [edema - conjunctiva, edema - cornea, edema - optic disc, edema - eyelid, edema - macula, edema - orbit]. Edema may be localized to several non-ocular tissues, such as the brain [edema - cerebral]. Important generalized causes of edema include congestive heart failure [heart disease], cirrhosis of the liver [cirrhosis - liver], hypoalbuminemia and the nephrotic syndrome [renal disease]. Edema can follow obstruction to the drainage of lymphatic vessels as in elephantiasis [lymphedema].