(Newser) – Italian surgeon Sergio Canavero said in 2013 that surgery to transplant a human head would be possible soon. Now he's set to announce a project to do just that, via a keynote lecture at the American Academy of Neurological and Orthopaedic Surgeons annual conference this June. He sees the procedure as being possible as soon as 2017 and believes it should be pursued as a means of saving people with, say, multi-organ cancer, reports New Scientist. But the obstacles loom so large—spinal cord fusion among them—that most surgeons the magazine contacted dismissed the proposal altogether. "There is no evidence that the connectivity of cord and brain would lead to useful sentient or motor function," a prominent surgeon said. But earlier this month, Canavero sketched out what he considers to be a viable procedure in Surgical Neurology International:

First he'd cool the head of the recipient and the body of the donor (he intends to use a brain-dead donor) to give their cells the ability to survive longer in the absence of oxygen; then he'd dissect neck tissue and reattach major blood vessels before severing the spinal cords—and severing them sharply is key, he writes. He proposes the use of a "specially fashioned diamond microtomic snare-blade" or a "nanoknife ... with a nanometer sharp cutting edge." But the most difficult part is fusing the two ends of the spinal cord; he believes polyethylene glycol could enable that. As New Scientist puts it, "Just like hot water makes dry spaghetti stick together, polyethylene glycol encourages the fat in cell membranes to mesh." A three- to four-week induced coma would follow. He believes the patient would be able to speak in his own voice upon waking and that walking could be achieved within a year. "If society doesn't want it, I won't do it," Canavero says. "But if people don't want it in the US or Europe, that doesn't mean it won't be done somewhere else." (Soviet surgeon Vladimir Demikhov was the first to try to transplant a head—a dog's—in 1954; read about his controversial experiments.)

