By Anja Burcak
While organ transplants are not uncommon, one scientist is pushing the transplant idea to a new extreme. Italian neuroscientist Dr. Sergio Canavero of the Turin Advanced Neuromodulation Group is hoping to successfully perform a human head transplant. That’s right, an entire head! Since his paper detailing the proposed surgical procedure was released in Surgical Neurology International, many people in the medical community have been debating the possibility of such a surgery being successful and the ethical nature of the proposal. The project titled HEAVEN/GEMINI is planned to be performed in the next two years.
A similar surgery has been performed before, just not on humans. In 1970, a head transplant was performed by Dr. Silver and Dr. White on a rhesus monkey. However, since doctors have yet to successfully connect the spinal cords of the transplant head to the donor body, the animal remained paralyzed. The monkey died several days later, suffering from extreme pain until its death. According to Silver, "it was just awful. I don't think it should ever be done again."
The plan consists of the HEAVEN process and the GEMINI process. The HEAVEN portion involves cooling the recipient’s head to a “hypothermia mode”, preventing neurological damage. The GEMINI portion involves cutting the spinal cords and connecting the head to the donor body. Canavero’s paper states that the most complicated part of the procedure lies in the connection of the donor’s and recipient’s spinal cords. He claims that today’s technology allows for the linkage to be done and details the technology for the procedure. A clean cut is key to disconnecting and connecting at the spine, needed for the fusion of the severed axons. Adhesives, such as polyethylene glycol (PEG) are to fuse the head and spine together. PEG has been used previously in dogs and guinea pigs to fuse spinal cords. Canavero argues that clean cuts could allow for the body to also naturally repair the nerves.
So, could this really happen? Silver has stated “to sever a head and even contemplate the possibility of gluing axons back properly across the lesion to their neighbors is pure and utter fantasy”. There are many complexities to consider, such as the human brain can only survive without oxygen for one hour. If such a procedure, however, were in fact possible, it is estimated to cost 12.6 million dollars, involve the participation of 100 surgeons and take 36 hours to complete. The targeted benefactors of such a procedure would be ill individuals, such as those with muscular dystrophies. One day not so far in the future, head transplants may be more than a just a story of science fiction.