Role of Perinasal Musculature in Ipsilateral Nasal Obstruction During Synkinesis Progression.

Facial synkinesis can lead to unintended activation of perinasal muscles, contributing to dynamic nasal obstruction. To determine whether targeted botulinum toxin injections, compared to no treatment, reduce new ipsilateral nasal obstruction symptoms in patients with facial synkinesis, as measured by patient-reported outcomes and the Nasal Obstruction Symptom Evaluation (NOSE) scale. A retrospective review was conducted of patients presenting with ipsilateral nasal obstruction and synkinesis at a multidisciplinary facial nerve clinic. Botulinum toxin (2-2.5 units) was injected into the supra-alar nasalis and depressor septi muscles. Symptom improvement was assessed at 4 weeks using patient-reported outcomes and the NOSE scale. Of 99 treated synkinetic patients, 23 (23.5%) reported new-onset nasal obstruction. Following chemodenervation, 74% experienced symptom relief, 4% had no improvement, and 22% were indeterminate. NOSE scores significantly improved from a mean of 44.86 to 28.93, with a mean difference of 15.93 (95% confidence interval: 2.86-29.00). Botulinum toxin injections targeting the perinasal musculature significantly improved nasal obstruction symptoms in patients with facial synkinesis.