Mixed Methods Investigation of Chronic Facial Paralysis in Individuals With Synkinesis: Study of Outcomes Before and After Treatment

Facial nerve paralysis is a devastating event that in up to 30% of cases may result in chronic weakness and/or the disfiguring condition of synkinesis, a long-lasting muscle discoordination of facial movement caused by aberrant facial nerve regeneration after facial nerve paralysis. This is believed to have a detrimental effect on social interactions, mental health, and quality of life.

Neuromuscular retraining therapy and ipsilateral chemodenervation into discoordinated muscles by injection (onabotulinumtoxinA/Botox, Allergan or incobotulinumtoxinA/Xeomin, Merz) are two common treatments for the abnormal muscle movements found in synkinesis. No study has compared the effectiveness of these treatment modalities for synkinesis. Retrospective data including our series at the University of Wisconsin Facial Nerve Clinic show significant benefit of retraining therapy using clinician- and patient-reported outcome measures. However, the manner in which this therapy may be optimized for use in treatment of the sequelae of facial paralysis is unclear. While literature shows beneficial improvement in outcomes with chemodenervation in prospective studies, no study has explored the effectiveness of physical therapy for synkinesis in a controlled, prospective manner. Further, the efficacy of therapy has not been shown to improve recognition and emotional information interpretation, both thought to be impaired in synkinesis.

This study has 3 specific aims:

AIM 1: Determine the effect of neuromuscular retraining or chemodenervation on clinician-reported and patient-reported outcomes. The primary outcome measure after four and eight months of treatment will be the clinician-reported Sunnybrook Facial Grading System (SFGS) scored on participant videos by blinded reviewers. Further, the investigators seek to measure the efficacy of treatment with existing patient-reported instruments. A correlation of clinician-reported outcome measure changes to changes in patient-reported instruments with treatment will be calculated, including the widely utilized disease specific Synkinesis Assessment Questionnaire (SAQ) and Facial Clinimetric Evaluation Scale (FaCE), and with two disease non-specific instruments, the Hospital Anxiety and Depression Scale (HADS), and Brief-Illness Perception Questionnaire (BIPQ). The efficacy of our clinical intervention will be measured with social-perceptual and mental health outcome measurement before and after treatment (AIM 3).

AIM 2: Determine the social, emotional, and functional burden of synkinesis, not captured in current patient-reported outcome measures as well as effect of treatment. Qualitative interviews with individual participants collected before treatment, after four months of treatment, and after eight months of treatment will be analyzed to study the burden of disease, experience with treatment, and potential differences in both treatments. The primary outcome is to identify the domains that may be missing from existing patient-reported measures collected in AIM 1. To do this, findings to assessment domains (i.e. decreased engagement, negative mood, etc.) in the FaCE, SAQ, and the two disease non-specific instruments, HADS and BIPQ will be compared. The investigators will then evaluate their findings based on domains in Patient-Reported Outcomes Measurement Information System (PROMIS) measures, an NIH-supported collection of validated and standardized scales.