The procedure, which is called a craniotomy in medical terminology, involves the removal of a piece of bone from the skull. It has been performed since prehistoric times: the oldest trepanned skull, found at a neolithic burial site of Ensisheim in France, is more than 7,000 years old, and trepanation was practised by the Ancient Egyptians, Chinese, Indians, Romans, Greeks and the early Mesoamerican civilizations. The procedure is still performed today, for both medical and non-medical reasons.
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