Non-invasive Trigeminal and Vagus Nerve Stimulation for Stroke Subjects With Chronic Upper Extremity Deficits

This pilot study proceeded in two phases: Phase I, an unblinded stage, and Phase II, a blinded stage comparing intervention and sham groups. Phase I consisted of 5 subjects, unblinded, receiving nTVNS. This phase tested the usability of the device and de-risked the use of nTVNS during rehabilitation. Visits included consent and baseline evaluation, followed by 6 weeks of treatment consisting of upper extremity rehabilitation paired with nTVNS. Rehabilitation and treatment occurred at a cadence of 3 sessions per week. Primary endpoints was collected after 6 weeks. Phase II consisted of a Prospective Randomized Open, Blinded Endpoint (PROBE) design with 11 subjects randomized to an intervention nTVNS group or a control sham stimulation group. Both groups received a stimulation tolerability assessment at the start of each session to support blinding for therapists and subjects. For the sham group, no stimulation was delivered during the priming or rehabilitation portions of the session. The same evaluations, sessions, and endpoints occurred as those in Phase 1.