The effects of botulinum toxin injections into the cricopharyngeus muscle of patients with cricopharyngeus dysfunction associated with pharyngo-laryngeal weakness

Abstract

This prospective, open study was carried out in order to assess changes in the swallowing and dietary status after injection of Botulinum toxin A (BoNT-A) into the upper esophageal sphincter (UES) in a series of patients with cricopharyngeus (CP) muscle dysfunction associated with pharyngo-laryngeal weakness during at least 1 year follow-up after treatment. Patients who had a cricopharyngeus (CP) muscle dysfunction associated with pharyngo-laryngeal weakness and who were at risk for aspiration were included in the study. The upper border of the cricoid cartilage was identified and the CP muscle localized using a standard electromyogram (EMG). The dose of BoNT-A was determined depending on the results of EMG performed just before the injection. Outcomes were assessed by the penetration-aspiration scale (PAS), the level of residue in the pyriform sinus and the National Institute of Health-Swallow Safety Scale (NIH-SSS) on a video fluoroscopic swallowing (VFSS) assessment, the patient's subjective impressions of their ability to swallow by the Deglutition Handicap Index (DHI), and changes in dietary status by the Functional Oral Intake Scale. Eleven patients underwent the complete assessment of swallowing function at 1, 3, 6, and 12 months. After the first set of treatment, seven patients had a good response and four did not respond. A significant decrease in the PAS score (p = 0.03), the amount of residue (p = 0.04) and the NIH-SSS score (p = 0.03) was observed 3 months after the injection in comparison with the first VFSS before the treatment. A relapse of dysphagia occurred in 3 out of the 11 treated patients; at 3 and 4 months for 2 patients with a Wallenberg syndrome, and at 11 months for a patient with cranial nerve paralysis after a surgery for a glomus tumor. Two of them underwent a second injection. One patient had a good response and remained stable for at least 1 year. The second did not respond either to the second injection or to a myotomy of the cricopharyngeal muscle. The third one is waiting for further surgery (myotomy). Therefore, at the end of the study and after a follow-up of at least 12 months, 5 patients out of the 11 enrolled had a good result. Percutaneous injection of BoNT-A into the UES can be a useful solution to improve cricopharyngeal dysfunction, despite the underlying pharyngo-laryngeal weakness.

Cricopharyngeal dysfunction: A systematic review comparing outcomes of dilatation, botulinum toxin injection, and myotomy

“…27 Although Terre et al recommended BoT injections for patients who had incomplete relaxation of the CP muscle with a certain degree of pharyngeal propulsion, Woisard-Bassols et al reported good outcomes in patients with CP dysfunction and pharyngolaryngeal weakness. 29 Our review found that BoT injections are not as successful as myotomy, and as the invasiveness of the procedure increased (BoT 5 low, dilatation 5 medium, myotomy 5 high), there was a statistically significant trend favoring increased success rates.…”

“…1). Twelve studies 4,8,22,[24][25][26][27][28][29][30][31][32] were prospective and 20 2,5,6,9,10,14,18,21,[33][34][35][36][37][38][39][40][41][42][43][44] were retrospective. All of the publications were observational studies, with a level of evidence of IV; with the exception of one prospective cohort study (IIb) ( Table II).…”

Botulinum toxin injection for hypercontractile or spastic esophageal motility disorders: may high-resolution manometry help to select cases?

“…This may explain the lack of effect of BTX treatment in some patients and maybe also the side effects. Electromyography guidance for BTX injection has been shown useful in pharyngeal dysfunction, but this cannot be applied to LES or esophageal body muscular layer . Endoscopic ultrasound (EUS) guidance has been proposed for esophageal BTX injection into the LES to treat achalasia, with good results .…”

“…However, drug therapies are often limited because of side effects or lack of efficacy . Surgical or more recently endoscopic esophageal myotomy has been proposed for the most severe cases …”

High Dose of Botulinum Toxin Type A (NT-201) for the Treatment of Dysphagia due to Severe Spasticity of Upper Oesophageal Sphincter: A Case Report

“…Myotomy of CM is the treatment of choice for the hyperactivity of the UES due to neurologic disorders [5], but it is generally suggested when other interventions have failed. BoNT-A has been widely reported as efficacious therapeutic medical tool for the treatment of dysphagia due to the spasticity of CM [6][7][8]. However, when using BoNT-A for the treatment of dysphagia, the doses that are commonly injected could result ineffective.…”