Optical Quantification of the Effect of Surface Electrical Stimulation to prevent Denervation Muscle Atrophy in 15 Patients with Facial Paralysis

Few studies show therapeutic potentials of functional electrical stimulation (ES) patients with facial palsy so far. Using 2D and 3D-fotographic documentation, we aimed to investigate whether ES would lead to morphologic changes towards facial symmetry. Only patients with one-sided peripheral complete facial paralysis confirmed by needle-electromyography (EMG) were included and underwent ES twice a day for 20 min until the event of reinnervation or for a maximum of 1 year. ES-parameters were set during the first visit and confirmed/adapted every month thereafter. At each visit, patients underwent EMG, 2D-fotographic documentation and 3D-videos. In total 15 patients were recruited (mean 53 years, min. 25, max. 78; 8 female, 7 male, median time of denervation 123 d). Following the ES protocol, they underwent ES for a mean of 201 d (min. 56, max. 377) without serious adverse events. While no ES being performed, smile angle in resting state (SA) decreased in patients with recent event of denervation. This effect could not be detected in patients being denervated ≥ 1 year. We could detect positive effects of ES on mouth corners height deviation immediately after ES. On long term, ES increased SA after 3 months. A positive short-term effect of ES on facial symmetry in patients with total paralysis could be shown. After decreasing while no ES being performed, SA increased under ES leading to improvement of symmetry of denervated faces. The improvement of optical appearance during ES represents a promising, easily accessible marker for effect quantification. Improving facial symmetry by ES might also be linked to preventing facial muscle atrophy.

DFG GU-463/12-1, MED-EL und IZKF

Publication History

Article published online:
12 May 2023