After doing much research for a project I'm working on for my insurance company, I strongly believe that the SphenoCath or Allevio cath or similar device(s) used for this treatment (neuromodulation for migraines) is considered to be Experimental/Investigational and is not, in fact. a nerve injection. In this case, it should be coded 64999, Unlisted Procedure (for the Nervous System).
The catheter is guided into the sinus cavity (often the middle turbinate) and Lidocaine is INSTILLED (not injected) into the cavity. After the procedure, the patient lies supine with their neck extended, for 10-15 minutes, so that gravity will help the Lidocaine (often viscous Lido is used) migrate deeper into the sinus. This is not necessary or required when an actual needle injection to a nerve takes place (think Novacaine at the dentist).
In that there are significantly reduced RVU's to using the Sphenocath, etc., than an actual nerve injection by needle would have, this procedure is more like instilling a medication into a bladder via a foley catheter. Patients can actually be trained to do it at home &/0r use long q-tips dipped in Lidocaine to accomplish the same thing. I certainly wouldn't attempt a nerve injection by needle at home!
If you have more specific questions that my research could help you with, please don't hesitate to message me. Because of what I do, I have to be a bit selective about what I can post.
Cindy R., BS, RN, CPC-A