PNS - Nerve block study

  • Research type

    Research Study

  • Full title

    Determination of feasibility of reversible conduction block generated using StimWave Peripheral nerve stimulator in treatment of focal spasticity and the stimulation parameters for the same.

  • IRAS ID

    307879

  • Contact name

    Deepti Bhargava

  • Contact email

    deepti.bhargava@thewaltoncentre.nhs.uk

  • Sponsor organisation

    Walton Centre NHS Foundation Trust

  • Duration of Study in the UK

    0 years, 3 months, 31 days

  • Research summary

    Dysregulated neural activity is responsible for many ailments: spasticity, reflex incontinence, etc. Current treatment options are suboptimal and include ablative procedures like neurectomy. Neurectomy leads to loss of function. Modulated electrical conduction block can help control this activity without causing additional loss of function and has immense potential in treatment of these conditions. Animal experiments have suggested that such a block is feasible. While safety ranges for delivery of current to human peripheral nerves are known and stimulation parameters for activation of nerves well established, further data is needed to assess the parameters for clinically useful conduction block.
    Peripheral neurectomy is used for treating focal spasticity. The procedure is performed under neurophysiology monitoring. Intra-operatively, the nerve is exposed and motor activity is recorded spontaneously and with direct bipolar stimulation with help of EMG electrodes placed in the territory of the nerve. Tetanic response obtained upon stimulation indicates spasticity. The nerve is cut and further testing done by stimulating proximal and distal to the cut. Lack of tetanic response after proximal stimulation indicates adequacy of procedure.
    We propose to briefly apply kilohertz frequency alternating current (used in SCS and PNS) via PNS device placed next to the isolated nerve in 2 patients undergoing neurectomy, just before cutting the nerve. So, after the nerve is exposed and tetanic stimulation confirmed, a high frequency blocking current will be applied where a cut is to be made. Proximal and distal stimulation will be done and response to stimulation checked as above. The PNSelectrode will be removed from surgical field and proximal stimulation done to confirm reversal of block. nerve will be severed, and further proximal and distal stimulation testing done as routine. The results will be compared to see if high frequency conduction block can physiologically mimic neurectomy; and obtain parameters of stimulation required for that.

  • REC name

    North West - Haydock Research Ethics Committee

  • REC reference

    22/NW/0038

  • Date of REC Opinion

    16 Feb 2022

  • REC opinion

    Favourable Opinion