Removal of tissue fragments for diagnostic purposes. There are many procedures for performing a biopsy and they can vary depending on the location of the disease. In general, a biopsy can be done by inserting a special type of needle through the skin. In some cases, this insertion can be guided by imaging examinations such as ultrasound, mammography, and tomography, among others. Generally, the biopsy procedure does not require hospitalization and is done under local anesthesia.