Ultrasound-guided, open-source microneurography: Approaches to improve recordings from peripheral nerves in man

Objective Microneurography is the only method for recording from single neurons in intact human nerves. It is challenging - requiring technical expertise, investment in specialised equipment and has sparse data yields. Methods We assessed whether ultrasound guidance in combination with an ‘open access’ amplifier and data capture system (Open-Ephys) would simplify and expand the scope of microneurographic recordings in humans. Results In 32 healthy consenting volunteers, ultrasound-guidance improved success rates for obtaining cutaneous C-fibres and reduced “Skin to Nerve” times from 28.5 minutes to 4.5 minutes for recordings of the peroneal nerve (P<0.0001). We illustrate the potential utility of ultrasound-guided microneurography for difficult to access nerves with phrenic nerve recording during a Valsalva manoeuvre. We show that Open Ephys is a viable alternative to commercially available recording systems and offers advantages in terms of cost and software customisability. Conclusions Ultrasound guidance for microneurography with Open Ephys facilitates cutaneous C nociceptor recordings and allows recordings to be made from nerves previously considered inaccessible. Significance We anticipate that the adoption of these techniques will improve microneurography experimental efficiency, adds an important visual learning aid and increases the generalisability of the approach.