[zadig]

I'm feeling incredibly bearish on this one. The central nervous system is not meant to be trifled with.

There are way too many questions here. What's the evidence for this? Two papers by two of his collaborators? How are neurons that have already degenerated in the brainstem due to the Werdnig-Hoffmann Disease going to be rescued? How is he going to reconnect different pathways between the brain and spinal cord if they have a different spatial distribution? So is the patient going to have the immune system of the donor body - if so, what does that mean for the head? What evidence is there that the visceral organs are going to be correctly modulated by the brain? What's going to happen to his collaborator's monkeys in a couple years?

[x5n1]

I don't see how this is suppose to work when we can not fix quadriplegic people. At the end of the day the only problem that they have is that the nerve connections are damaged. So if we can't fix that how do we move on to something so much more complex like this.

edit: Answer is here under Gemini, which claims to use a unique procedure to fuse the severed nerve bundle together, after doing a very clean cut.

http://surgicalneurologyint.com/surgicalint_articles/heaven-...

[serf]

> don't see how this is suppose to work when we can not fix quadriplegic people.

folks with spinal cord injuries are often that way not due to injury caused by trauma itself, but due to their bodies reaction after that trauma. Swelling and inflammation near the damage leads to contusion of nervous tissue and the formation of scar-tissue like plaques that reduce the effectiveness of myelin as an electrical material. We can't repair that form of damage yet, only hope to limit it through quick response after trauma.

The HEAVEN paper goes through the steps they are going to take to make sure that the body is not allowed to react in such a way. A very sharp blade is used and a chemical, PEG, is used to refuse the nervous tissue within a small very small time-frame, along with chilling the patient and other protocols.

tl;dr : a spinal cord injury is tricky because the overall amount of bandwidth between the brain and the nervous system is reduced (so-far) irreversibly.

This surgery is tricky (amongst a zillion other reasons) because rather than dealing with a reduction in bandwidth, it's hoped that the brain is plastic enough to be able to deal with the different spatial characteristics of the patients nervous tissue and matching body.

even shorter tl;dr : it's easier to manage an injury you made than one you were handed.

(p.s. tetra/quad/para-plegia are symptoms, not diseases. the causes are numerous and plentiful. i'm only using spinal cord injury as an example because I am more familiar with it than other diseases that cause paralysis)

[Camillo]

In that case, could you make two ultra-precise cuts above and below the lesion, and connect the stumps with a piece of the spinal cord of a brain-dead patient, similarly cut? Would that not be worth trying first?

[rayiner]

I assume that's the point of the diamond nanoblade: to be able to cut the spinal chords without the sort of extensive, uncontrolled, tissue damage you might see in a quadriplegic.

[DougN7]

I came here to say exactly that.