Use of high-resolution endoscopic ultrasonography to assess esophageal wall damage after pneumatic dilation and botulinum toxin injection to treat achalasia.

OBJECTIVE: The purpose of this study was to utilize high-resolution endoscopic ultrasonography to assess esophageal wall damage in patients with achalasia treated by either pneumatic dilation or botulinum toxin injection and to compare their symptomatic response.
METHODS: Twenty-nine patients were treated with pneumatic dilation (11) or botulinum toxin injection (18) in a nonrandomized, controlled manner. An achalasia balloon dilator inflated at the gastroesophageal junction was used for dilation. Botulinum toxin was injected during endoscopy into the gastroesophageal junction. Endoscopic ultrasonography was performed at the level of the diaphragm before, immediately after, and 24 hours after treatment. Symptoms were assessed before and 7, 30, 60, and 90 days after therapy.
RESULTS: The mucosal-submucosal thickness increased significantly immediately after pneumatic dilation, but normalized by 24 hours. No significant change in mucosal-submucosal thickness occurred after botulinum toxin injection. No significant alteration in muscularis propria thickness was observed after either procedure. Dysphagia and regurgitation improved significantly at 7, 30, 60, and 90 days after both procedures.
CONCLUSIONS: Pneumatic dilation produced transient thickening of the mucosa-submucosa, but no thickening or breaks in the muscularis propria. This transient wall damage suggestive of edema was not seen after botulinum toxin injection. Over a 3-month period, botulinum toxin was equivalent to pneumatic dilation in relieving dysphagia and regurgitation in patients with achalasia.