The first human head transplant is due to take place in 2017. Photo: IC

 

Thirty-year-old Russian computer scientist, Valeri Spiridonov, has made a bold decision. He will allow his head to be cut off and attached to another body. If everything goes smoothly, he will live with a different healthy body, instead of his own. He has been suffering from incurable muscular atrophy, which has gradually paralyzed his whole body.

"My decision is final, and I do not plan to change my mind," Spiridonov told the Daily Mail on September 9. "I want the chance of a new body before I die."

To give Spiridonov another chance at life, a neuroscientist from the University of Turin, Sergio Canavero, has been working hard to realize this dream.

Canavero, who is set to lead the transplant team, visited China last month to consult with another expert, Ren Xiaoping at Harbin Medical University in Heilongjiang Province. The famous microsurgeon has also been doing research for years in this seemingly unbelievable field. The pair discussed the plan of conducting the first human head transplant surgery.

According to the Daily Mail, Canavero announced at a science conference themed "Frontier Science" in Harbin, that he would form a medical team with Ren on Spriridonov's case to try and give him a new, healthy body. The surgery is set to be done by 2017 in the Affiliated Hospital to Harbin Medical University.

"Now the technology for head transplantation is still being developed," Ren told China Newsweek on September 11. "If everything goes smoothly, the surgery will be carried out in December, 2017."

Head transplants, also known as allogeneic head and body reconstruction, means transplanting one person's head to another person's body. Canavero and Spiridonov's case will be the first head transplant surgery between humans, and they face high risks and great technological and ethical challenges.

Intricate procedure

Canavero calls head transplant surgery "heaven surgery," which comes from its scientific name "head anastomosis venture." As early as 2013, Canavero announced that the surgery could save patients who suffer from incurable diseases such as cancer and general paralysis.

At almost the same time, Spiridonov heard about the crazy yet magical surgery of head transplantation for the first time. He immediately made contact with Canavero, and told him that he wanted to be the first human volunteer for the surgery.

On April 8 this year, he officially announced his decision to "entrust" his head to Canavero and his team to be transplanted to a potential donated body. He would accept the result, no matter how it turned out, he said.

The reason for Spiridonov opting for a seemingly impossible surgery is that he has been living in pain his whole life. He suffers from Werdnig-Hoffman muscle wasting disease. Patients experience the atrophy of all their muscles, even the respiratory ones.

Although Spiridonov is very lucky to have survived this long, his body is in an extreme state of atrophy and he can not take care of himself, with the result his quality of life is extremely poor.

"I hope I can get a healthy, young and strong body, but I know it's a gamble," said Spiridonov at the science conference in Harbin. "I know the risks and I am not insane."

The issue of a potential donor body has also sparked controversy. According to a xinhuanet.com report on September 12, permission will be asked from the relatives of a person in a persistent vegetative state, or a prisoner facing the death penalty will be asked to donate his body.

In one paper Canavero published in the Journal of Neurosurgery in February, he described the key points of head transplant surgery.

An extremely sharp knife, which can be specially made from a diamond, or a nano-scale thin blade made from silicon nitride, is needed. The sharp blade is needed to ensure a clean cut from both bodies, to make it easier to attach the head to the donated body.

The head must be severed quickly and cooled down to 10-15 C. The whole surgery must be completed within one hour - including stitching up the muscles and connecting the blood vessels and nerves and fusing the spinal cord with a special glue of polyethylene glycol.

According to a TED speech delivered by Canavero in April 2014, the spinal cord's connection will be the most difficult and important.

After the surgery, the patient will be put in an induced coma in a low temperature environment for about four weeks, while the head and body heal together and autonomous respiration and heartbeats appear.

Surgery of the future

This operation sounds more like science fiction than reality to many, however, surgeons believe the transplant is really possible in the near future. Research into head transplants is constantly evolving.

"The reason a head transplant has been viewed as impossible, is because of the difficulties of central nerve system regeneration, immunological rejection and ischemia reperfusion injury, but now we are able to resolve these problems," said Ren in a people.cn report in July.

Ren also stressed the great significance of a head transplant. "It is absolutely needed in clinical medicine to help cure incurable patients with systemic disease but a relatively healthy brain, and it will play a positive role in global medical science development."

Since 2013, Ren has transplanted the heads of over 1,000 lab rats. To date, the longest surviving record is about one day.

According to Ren's paper published in the medical journal CNS Neuroscience and Therapeutics in 2014, many rats could breathe and blink with steady heartbeats after undergoing head transplants. They did not show any body stiffness caused by spiral cord injury. In the paper Ren also mentioned that primate animal tests will be done after more positive effects are seen in lab rats, an announcement that has attracted much global media attention.

"Humankind dreamed of flying, and thought it was impossible, but now we have made it real, even flying to the moon," Ren told the China Newsweek. "Many impossible things today are possible tomorrow, including head transplants."

Experimental research

Actually, many years before Ren and Canavero, scientists were already studying head transplants.

According to a Southern Weekly report in July, as early as 1908, a doctor in the US named Charles Guthrie did the first head transplant surgery on two dogs.

He cut one dog's head off and transplanted it on another dog's neck, stitching up the blood vessels and muscles, giving the dog two heads.

According to Guthrie's records, the transplanted head showed pupillary constriction and could even stick its tongue out, but lost its vital signs after a few minutes, and the transplant failed.

In the 1950s, with the transplant technology advancing, another doctor Vladimir Demikhov from the former Soviet Union, did similar head transplant surgeries on 40 dogs. The heads survived for an average of two to six days, and the longest survived 29 days.

Demikhov's head transplant experiments contributed greatly to the science of organ transplantation. Since then, organ transplant technologies have advanced considerably and immuno-suppressants have made it possible to transplant organs such as hearts, kidneys, and livers.

In 1970, Robert J. White, a neurosurgery professor in the US conducted head transplant surgery on two monkeys. He cut off their heads and transplanted one head to the other's body. After the surgery, the monkey was able to open its eyes, drink liquid, and even tried to bite the researcher, but it was paralyzed below the neck.

In 2001, White conducted 20 more surgeries and the longest survival time of the recipient monkey was eight days.

Ethical issues

Compared with other organ transplants, head transplants have more severe ethical challenges.

According to the Southern Weekly report, a doctor cutting off a living person's head may be considered to have committed murder. Even if it is legal and the transplant is successful, after the surgery, the patient will be faced with an identity dilemma.

In the 1970s, after White conducted head transplants on monkeys, he was criticized and condemned by the public. Some animal rights campaigners threatened to kill him, his research funding was suspended, and people likened his head transplantation surgery to the science fiction work, seen in Frankenstein (1931).

In the movie the crazy scientist sewed different body parts together and created a monster.

Today, Canavero and Ren's head transplant plans are also being condemned. It is highly likely that this surgery could lead to death, and the surgery will be strictly censored by the ethics committees of related countries.

According to Ren, transplantation is always a controversial topic. "Twenty years ago when we studied hand transplantation, we were criticized but we insisted on doing it," said Ren.

"After we succeeded, people accepted it. Head transplantation is a much bigger issue, and is sure to face even more resistance."

But Ren is adamant that the development of medical science will not stop because of ethical disputes. "There are always twists and turns in the development of modern medical science, but clinical medicine will take the ethical concerns into account," said Ren. "I am ready to accept the risk of failure, for I have to bear world-class risk if I want to challenge a world-class topic."

Global Times - Agencies