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

Abstract

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 min to 4.5 min 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.

Keywords: C-fibre; Microneurography; Nociceptor; Open-source; Pain; Ultrasound.