Cricopharyngeal Botox injection: indications and technique.

PURPOSE OF REVIEW: Botulinum injection is a widespread technique for treating oropharyngeal dysphagia although there are no standards or guidelines. Based on the literature review we try to make some recommendations.

RECENT FINDINGS: In the last 12 months molecular and pharmacological research has reported the working mechanism of the various botulinum toxin types which tries to explain former clinical observations such as variable response rate and therefore dosage, and toxin type specific resistance. Recent dose-ranging studies or comparisons of different toxin preparations or types rarely focus on oropharyngeal dysphagia.

SUMMARY: Injection of botulinum toxin A should be considered in cases of relative hypertonicity of the cricopharyngeal muscle and has an onset around day 7 and an offset of at least 4 months. The technique is simple and the complication rate is extremely low (7/100). There are some conditions for success: injection in the horizontal part of the cricopharyngeal muscle, and a high enough start dose. Botulinum injection may be preferred over surgical myotomy because of the low risk, low cost and effectiveness of the procedure. Only in cases of BoNT/A resistance should other toxin types be used.