title: Esophageal achalasia: intrasphincteric injection of botulinum toxin A versus balloon dilation.
abstract: OBJECTIVE
  In patients with esophageal achalasia, pneumatic dilation is the treatment of choice, but it bears the risk of perforation in about 4% of cases. A new nonsurgical method, intrasphincteric injection of botulinum toxin A, has shown promising initial results, and we thus undertook this study to compare the long-term outcome of these two methods.
  
  
  METHODS
  In a prospective randomized study, 24 patients with definitive esophageal achalasia were divided into two equal groups and underwent either balloon dilation or injection of botulinum toxin (20 U injected into each of the four quadrants in the lower esophageal sphincter). The outcome was assessed on the basis of a symptom score documented before treatment and at regular intervals for two and a half years thereafter. Complications associated with the two techniques were also documented.
  
  
  RESULTS
  No relevant complication occurred in either of the treatment groups. Initially, dilation was successful in 10 of 12 patients (83%), and botulinum toxin injection in 9 of 12 patients (75%). The symptom scores showed no significant differences between the two groups before and one month after treatment. Over the two and a half year follow-up, however, all nine successfully treated patients in the botulinum toxin group experienced recurrence of symptoms, but only four of the ten patients (40%) in the dilation group.
  
  
  CONCLUSIONS
  The two treatment methods initially had equal success rates, but in the long term the effect of the botulinum toxin injection was statistically significantly shorter than that of balloon dilation. As fewer risks are associated with the injection treatment, studies should be undertaken either to identify patient subgroups in whom botulinum toxin can be effective long-term or to test substances with longer-lasting effects.
authors.affiliation: Department of Medicine I and Medical Informatics, Biometry and Epidemiology, University of Erlangen-Nuremberg, Erlangen, Germany. steffen.muehldorfer@med1.med.uni-erlangen.de
authors.forename: S M
authors.initials: SM
authors.lastname: Muehldorfer
authors.forename: T H
authors.initials: TH
authors.lastname: Schneider
authors.forename: J
authors.initials: J
authors.lastname: Hochberger
authors.forename: P
authors.initials: P
authors.lastname: Martus
authors.forename: E G
authors.initials: EG
authors.lastname: Hahn
authors.forename: C
authors.initials: C
authors.lastname: Ell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000627:therapeutic use*; D002404:Catheterization; D004931:Esophageal Achalasia / Q000628:therapy*; D005260:Female; D006801:Humans; D015552:Injections, Intralesional; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D011446:Prospective Studies; D012008:Recurrence; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A