Ancient civilisations practised surprisingly advanced neurosurgery in Peru. We get inside the head of the matter

If you take a flight northwards up the Peruvian coast, the imposing enormity of South American geography makes itself clear. The Pacific ocean laps against the arid, dusty coastline. Further inland, the craggy, relentless peaks of the Andes protrude from the scudding clouds and beyond this the green, expansive mass of the Amazon stretches on for infinity.

Down below, civilisation has made its mark with sporadic towns lining the coastline. Yet these habitations mask previous lives of intrigue hidden away in the scrub. Only a few centuries ago, an area the size of Western Europe was playground to the Moche and Inca civilisations. When these indigenous communities were ransacked by Spanish conquistadores in the late 1500s, their cultural legacy became as scattered as desert sand blowing in the wind.

Detail of Trepanation, from the History of Medicine in Mexico, fresco painted by Diego Riviera, 1953: Child having his skull trepanned

Archaeologists have been working hard

Fortunately, archaeologists have been hard at work. Among the tombs of the decorated dead, they uncovered archives of war and evidence of extensive medical activity. The apparent sophistication of the treatments is staggering when compared with the level of technology in this period. In particular, brain surgery was so widely practised that a 15th century equivalent to a centre of excellence was created. One modern day neurosurgeon summed up this finding with a surprisingly humbling comparison: "I would assume that the ancient warrior realised very early on that it was easiest to annihilate his opponent with a blow to the head. Therefore, the concept of head injury remains as ancient as the powers of solicitation of the opposite sex. It has often been said that the two oldest professions are prostitution and neurosurgery."¹

Yet, there was more to this than dealing with the carnage of an occasional rock bashing episode on a distant plain. Skulls were intentionally deformed to give members of the nobility a more distinct identity. There was a great keenness in performing craniectomies. Sucking the brain out through the occipital bone was a necessary step in obtaining that ultimate trophy of war--the dried, shrunken skull.

Nevertheless, the delicacy with which the surgeons performed lifesaving operations is patently clear. They would preserve crucial intracranial ridges,² having learnt from previous mistakes. Further studies of skulls have revealed low infection rates--most likely due to the use of herbal antiseptics passed down through the ages. Healing and recovery was found to have occurred in up to 70% of cases. Putting this in context, cranial trephination (skull puncture) in 18th century Europe yielded 100% fatality rates.

An ancient Peruvian trepanned skull with an example of the knife used to do it

The tools challenged today's kit

The array of tools was enough to challenge any current day surgeon's tray of kit. Knives made of volcanic crystal cut bone, and chisels of bronze accompanied copper forceps and suturing needles in the armoury. Wool tourniquets helped provide haemostasis and cotton bandages absorbed any ooze. What was used as an anaesthetic is less clear. Various theories about coca (the plant from which cocaine is derived) have been aired, but no concrete evidence exists. The more likely explanation is that the ancient Peruvians underwent a similar method to every other individual who was ever in pain before the discovery of chloroform--they got very, very drunk.

Despite the apparent dexterity and pragmatism of these surgeons, would you want to be one of their patients? In 1944, a couple of Peruvian surgeons decided to take ethical jurisprudence to the boundaries of credibility.³ They found a "suitable" subject--a 22 year old girl who had been walking along when a tree fell on her head. She suffered a depressed cranial fracture, Jacksonian epilepsy and dysphasia. Applying dubious standards that would have our national press baying for slaughter, they implemented their management plan. Only pre-Columbian surgical implements would be used, but they allowed some comforting, 20th century ice chips to reduce the

postoperative swelling. After hours in theatre battling with their new found toys, success seemed imminent. They had applied a tourniquet made from llama wool and opened the skull with an obsidian silex chisel. A few sulphur crystals were slipped inside in place of antibiotics and the wound was sewed up with a special Incan needle. She was apparently "perfectly well after the procedure and had a good recovery."

As if the Incan gods bore a grudge against this hijacking of their culture, she died of a bronchopulmonary infection seven days later. The nurses pointed out that she had been sucking the ice chips from her head pack during the night, believing it was ice cream. The source of infection became clear and the irony hit home.