Skulls from ancient graves show that trepanning was practiced in many pre-civilization cultures including Egypt, Celtic cultures, China, India and Polynesia. But most skull finds come from the South American civilizations (Aztec, Mayan and Inca). During historic times it was practiced in Bolivia and Peru.
Inca surgeons often inserted a silver plate to close the hole. The degree to which the skull bone covered the plate is a good indication for the patient's life span after the operation.
In 1962, a Peruvian neurosurgeon performed the technique using Aztecan tools in a modern setting on a head-trauma victim. The patient survived.