Facial muscle reanimation by transcutaneous electrical stimulation for peripheral facial nerve palsy

Effect of pulse waveforms on movement amplitudes and perceived discomfort in electric muscle stimulation in unresolved facial nerve palsy

“…We recruited 11 participants (7 females, 4 males), aged 24 to 62 years (M=46, SD=11) from a pool of 14 people from our previous study investigating electrical stimulation for unresolved peripheral facial nerve palsy [16]. Three individuals from the original pool who had had either a symmetrical function of the frontalis muscle (n=2) or showed no movement response to electrical stimulation (n=1) were excluded from the study.…”

“…However, even in such cases, FES has shown potential for muscle regeneration and muscle fibre excitability [14,15]. In a peripheral facial nerve palsy the denervation may not be complete even if the muscle appears clinically paralysed and in these cases it can be possible to produce movement by electrical stimulation [16]. Currently, there is no substantial evidence on the benefits of electrical stimulation for the rehabilitation of facial nerve palsy [17], although some studies have suggested that it might be beneficial [18].…”

“…The aim of this study was to electrically stimulate the frontalis muscle of individuals with an unresolved facial nerve palsy with two different pulse waveforms, square pulse and enveloped sine pulse (sinusoidal wavelet), and investigate their effects on the muscle activation and the perceived discomfort. Due to its anatomical location, the activation of the frontalis muscle is easy to measure, and its stimulation does not significantly spread to other facial muscles [16,38] which makes it an ideal target muscle to study the effects of the stimulation.…”

Functional electrical stimulation for facial pacing: Effects of waveforms on movement intensity and ratings of discomfort

“…Transcutaneous FES could potentially also provide an alternative for chronic patients who do not want to undergo surgery. Importantly, a recent study by Mäkelä et al [13] showed that the activation of chronically paralyzed facial muscles by transcutaneous electrical stimulation was possible even in some cases where the muscles were clinically completely paretic if a subclinical innervation exists. Transcutaneous FES techniques are also needed to study the potential and possibilities of long-term use of facial FES systems.…”

The Regenerative Potential of Facial Nerve Motoneurons following Chronic Axotomy in Rats

“…Although many molecules involved in facial nerve repair have been characterized, the precise mechanisms of nerve regeneration remain unclear. Interestingly, some studies have demonstrated that electrical stimulation could promote peripheral nerve regeneration or the functional recovery of paralyzed facial nerves and nerve reinnervation of paralyzed muscles [ 24 – 26 ]. However, the mechanism by which electrical stimulation promotes nerve regeneration is unclear, and we speculate that it may be related to the electrical stimulation of the peripheral nerve, which activated the regenerative or functionally protective neural signaling pathway.…”