P1-5-02. Evaluation of facial muscle elasticity with real-time tissue elastography – Examination in cases with synkinesis following peripheral facial nerve paresis

Abstract

The study was performed to clarify the relationship between facial muscle elasticity measured by real-time tissue elastography (RTE) and the clinical phenotypes of peripheral facial nerve paresis (PFP). We examined the orbicularis oculi muscles of nine PFP patients with synkinesis by RTE. The strain ratio (SR) of the muscle to an acoustic coupler was calculated as an index of muscle elasticity. We also recorded and integrated electromyograms of left and right orbicularis oculi muscles, respectively. The value on the affected side was divided by that on the healthy side. The value obtained in the resting state was defined as Contracture Index (CI), and that in the whistling state was defined as Synkinesis Index (SI). We studied the correlation between SR and various clinical phenotypes including CI, SI, age, the degree of paralysis, the duration of therapy, the degree of facial asymmetry, and the degree of synkinesis. The degree of paralysis was negatively correlated with SR ( ρ = −0.86, p