Cricopharyngeal myotomy and toxin botulinum injection for the treatment of upper esophageal sphincter disorders: a narrative review

To assess the indications, safety, and results of cricopharyngeal myotomy (CPM) and toxin botulinum injection (TBI) for the treatment of upper esophageal sphincter (UES) abnormalities. The UES disorders can provoke overwhelming consequences such as bronchopulmonary aspiration, malnutrition, impaired quality of life or even death. The best treatment modality for UES disorders remains unclear. The purpose of this review was to assess indications and outcomes of CPM and TBI for the treatment of UES abnormalities. We performed a review of the literature regarding the outcomes of CPM and TBI for UES disorders. All articles between 1990 and 2020 describing CPM, TBI, or those comparing both techniques were analyzed. Treatment indications, safety, and outcomes of both procedures were evaluated as primary endpoints. Quality of life improvement was evaluated as a secondary endpoint. Outcomes after CPM and TBI for UES disorders are heterogeneously reported. Data suggest that both surgical and endoscopic CPM are safe and have encouraging long-lasting results in terms of symptoms relief and quality of life improvement. TBI is also a safe procedure, with good but temporary postoperative results. Current data are heterogeneous and show that both CPM and TBI are safe and effective treatment modalities for UES disorders. Better long-lasting effects, however, seem to be achieved with CPM.