Brain abscess (or cerebral abscess) is an abscess caused by inflammation and collection of infected material, coming from local (ear infection, dental abscess, infection of paranasal sinuses, infection of the mastoid air cells of the temporal bone, epidural abscess) or remote (lung, heart, kidney, etc.) infectious sources, within the brain tissue. The infection may also be introduced through a skull fracture following head trauma or surgical procedures. Brain abscess is usually associated with congenital heart disease in young children. It may occur at any age but is most frequent in the third decade of life. Although brain abscess is relatively rare, it is a complication encountered increasingly in patients whose immune systems have been suppressed either through therapy or disease.