- Austin and Lee burr hole system. USA. 1956. The basic design consisted of a device mounted on a burr hole in the skull. It allowed guidance at various angular adjustments. By passing the needle through the trephine after attaching the socket, AP and lateral x-rays were taken and angular adjustments of the ball were made to direct the probe to the target and to calculate the length of insertion. After the needle was passed to the target, repeat x-rays were taken to confirm the position in the target. The plastic version weighed two ounces and cost thirty-seven dollars. It was a popular instrument used to treat Parkinsonism.