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Lesion - Definition

In medical jargon, the lesion is a term that brings together all the abnormal biological tissue changes. It may be just a cut, a burn, a wound. It may also result from the action of a pathogen such as parasite or infection as well as metabolic, physiological or immune disorder.
In all cases, the lesion is any tissue damage. Note that some lesions may be caused in order to treat a disease. For example, surgical removal of part of the brain was performed in some patients with epilepsy.