Hi, I don't have spasmodic dysphonia, what I have is Oropharyngeal dysphagia, Cricopharyngeal achalasia and Paralysis of left vocal fold. There are some differences. I had some surgeries in Mayo Clinic, one of the restilane injection in the vocal chord. Sadly it didn't work for me, after that I had some fat removed from me and inyected, didn't work either. I felt really desolated. Without being able to talk nor eat I felt really isolated from the world, it was very difficult. What finally worked for me was seing a specialist. I went to Dr Milan R. Amin in NYU Languone Health (NYC) and after some consultations he suggested a surgery in which he changed my vocal chords and implanted a new one. For my dysphagia he did a ablation of my esophagus, an both have helped me a lot. After that I did speech therapy because the therapy I did before didn't work because I had no vocal chord.
Hope this helps a little bit 🙂 let me know if I can be of any additional help