Has anyone had nerve biopsy to determine type and cause of neuropathy?

I’m not sure if this will answer your inquiry re testing for viability of nerves, presumably for PN in the feet.

I had a ‘perfusion study’ where neurologist uses an electric pin pricking device across the bottom of the feet.
While it’s not comfortable it’s tolerable. I would do it again without reservation.

I would not guess that there’s a systemic biopsy because of the branching and localization issues, e.g. nerve problems in feet may not affect the hands, head, eyes, et al.🤷🏼

I’ve had a skin punch biopsy, which ruled out Parkinson’s and indicated small fiber neuropathy. I have an appointment in April at John Hopkins neurology dept to confirm if it’s SFN and if so, what’s causing it. I think the biopsy is well worth it. The doctor cleared it with Medicare, and the covered it.

I read an article regarding genetic testing and gene therapy for neuropathy. Has anyone tried this and what effects did it have? I'd like to bring this up with my neurologist.

Thank you for your response. I had the above test done last summer. And yes, it is not uncomfortable. Nothing showed up then, but my symptoms have worsened and the neurologist suggested a skin punch biopsy.

Thank you for your comment. What does the biopsy entail? I scheduled one for the spring.
I just recovered from a bout of COVID and found it to have amped up my symptoms. I'm hoping they diminish. Our freezing cold temps are not helping either.

The procedure doesn't take much time. There's no prep required, and the doctor does it in their office. You get a topical numbing agent, and then there are three spots where the doctor takes a tissue sample. The pain is about the equivalent of getting a shot or having blood taken. Mine healed up quickly, and I got the results in 3 weeks. Thanks to the answers provided by the test results, my neurologist and I were able to figure out which specialist I should see. I finally feel as if I'm not just running in circles!