While the sight of drills, saws and knives can bring a grimace to even the most tempered face, it is this very macabre fascination that likely fuels the passion of many collectors. Trepanation, or the drilling of a hole in the skull, is one of the oldest surgical procedures, some trepanned skulls even dating back to 3000 B.C. The oldest skulls have been found in the Danube Basin, but trepanned skulls have been found in virtually every country, even in America, with the highest concentration found in Peru and Bolivia. The word trepanation is derived from the Greek, meaning "auger or borer". More specifically, trepanation means "an opening made by a circular saw of any type". Trepanation has been performed over the centuries for various reasons, including a means to liberate the demons or spirits from the heads possessed. Trepanation was also performed for therapeutic reasons, such as for epilepsy, headaches, infections, insanity, and a whole range of maladies. A third reason for trepanning is religious, where the rondelles, or disks of bone from the skulls, were collected and used for charms and talismans which were believed to have power to protect the wearer from illness and accidents. Nowadays the procedure is believed to help the individual expand his or her consciousness, and initiate a spiritual awakening that leaves the trepanned individual forever changed.
Keeping in mind that anesthesia would not be developed until the late 19th century, it is hard to imagine anyone volunteering to have their head wedged between the knees of the surgeon and their skull sawed open, and records indicate that very few survived. For that reason, many of the advances and developments in such surgeries and instruments were achieved at the grave expense of patients who had been committed to insane asylums and had little choice in the matter. Surgeons also employed various skull saws, most often convex in shape with serrations on both sides of the central handle. These saws with varying degrees of curve and design were known as Heys saws named after their inventor and were used to saw through the cranium.
Most neurological instruments are found in boxed sets with earlier and rarer 16th- and 17th- century examples being more ornate than later models. A typical neurosurgery set might include a set of skull saws, at least two trephines of varying diameter, scalpel, elevator for raising the bone after it has been cut, a brush for removing small skull particles, cranium forceps and a lenticular for depressing the brain.
