Botulinum toxin can unfold into a length of thirty–forty five mm from the injected muscles on the adjacent muscles, whether or not these muscles are divided by fasciae. Neck muscles are liable to diffusion of botulinum toxin, and paralysis of the incorrect muscles leads to dysphonia, dysphagia or dystonia. https://botulinumtoxins20741.blue-blogs.com/43136521/the-basic-principles-of-botulinum-toxins-mechanism-of-action