Causes
Lesions are caused by any process that damages tissues. Lesions can also be caused by metabolic processes, like an ulcer or autoimmune activity, as in the case with many forms of arthritis.
Lesions are sometimes intentionally inflicted during neurosurgery, such as the carefully placed brain lesion used to treat epilepsy and other brain disorders. (See Ablative brain surgery.)
Note that lesions are not limited to animals or humans; damaged plants are said to have lesions.
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