Intrasphincteric botulinum toxin versus pneumatic balloon dilation for treatment of primary achalasia

Despite a high success rate, pneumatic dilatation for achalasia is accompanied by a significant risk of esophageal perforation. Injection of botulinum toxin (botox) into the lower esophageal sphincter (LES) can lead to improvement in symptoms with reduced risk of complications. Direct comparisons of the two techniques are needed to define their role in clinical management.

We compared pneumatic dilatation to botox for patients with achalasia using a double blind, randomized study design. Patients underwent clinical, manometric, radiographic and endoscopic evaluation to confirm primary achalasia. They were randomized to receive either 80 units of botox into the LES or Witzel balloon dilatation. Patients also received sham dilatation or injection, respectively. The patients and investigators assessing symptom response were blinded to therapy. Symptoms and esophageal function were assessed at 3 weeks, 3 months and 1 year after therapy. Treatment failure was defined as the lack of decrease in symptom grade more than 1 or recurrence of symptoms. Patients with treatment failure crossed over to the alternative treatment.

Thirty four patients were studied, and 31 completed the trial. Of the 18 patients randomized to Witzel dilatation, 16 (89%) of 18 remained in clinical remission. Of the two patients with treatment failure, one responded to botox injection. Of the 16 patients randomized to botox, (38%) 6 of 16 remained in clinical remission. Four patients had initial failure, and 6 relapsed at a mean of 4 months after therapy. Of the nine patients who crossed over to dilatation, seven responded well, but two required surgical management of perforation. Although both treatments had excellent initial clinical improvement, patients randomized to Witzel dilatation had superior long-term success ( < 0.01).

Initial therapy with Witzel dilatation is associated with better long-term outcome than a single injection of botox. Because of the risk of endoscopic perforation, botox remains a viable alternative to dilatation.