The Development of Synkinesis after Facial Nerve Paralysis

Abstract

In this study, the development of clinical synkinesis after facial nerve paralysis (FP) and its relationship to electrophysiological findings were investigated. Thirty-four patients who were examined within the first 5 days after onset of FP and who could also be followed up for at least 4 months were included in the study. Electrophysiological investigations consisted of: (1) recording of the direct responses by facial nerve stimulation at the stylomastoid fossa; (2) recording of the ‘synkinetic spread’ of the supraorbital nerve reflex to the lower facial muscles; (3) recording of the ‘lateral spread responses’ by stimulating the mandible and zygomatic branches of the facial nerve. Clinical synkinesis developed in 14 of 18 patients (78%) with a direct response ratio (DRr) of less than 40%. Among the 16 patients with a DRr of 40% or more, synkinesis was observed in 3 cases (18.7%) only. The DRr provided reliable information concerning the development of synkinesis. Forty percent seemed to be a reasonable limit to distinguish the high-risk group for the development of clinical synkinesis.

Prognostic factors of Bell's palsy: Multivariate analysis of electrophysiological findings

“…The number of sequelae is more frequent and higher in subjects with residual paresis. 15,29 Neuropraxic lesions, which usually evolve to a complete recovery, can be distinguished from axonotmesis/neurotmesis lesions, 30 which may evolve to residua, 31 by using electrophysiological testing.…”

Therapeutic Strategies in Post–Facial Paralysis Synkinesis in Adult Patients

“…Celik et al 8 applied facial nerve stimulation in 34 patients within the first 5 days after the onset of facial palsy. Facial movement responses, the appearance and spread of synkinetic movements, were recorded clinically and electrophysiologically.…”

Current considerations in the management of facial nerve palsy

“…Following recovery from Bell's palsy, 15-20% of patients develop facial synkinesis [35,36], stemming from aberrant nerve regeneration. Facial synkinesis is characterized by findings such as eyelid closure and epiphora with mastication, as well as aberrant facial and neck contraction with volitional movements.…”