Findings
The BaSw demonstrates a dilated esophagus with tertiary contractions and a bird beak appearance to the lower esophageal sphincter characteristic of achalasia.
Discussion
Primary/idiopathic achalasia results in failure of relaxation of the lower esophageal sphincter with secondary disruption of esophageal peristalsis. It is treated by dilatation. Secondary achalasia is caused by a lesion of the brain, vagus nerve, or esophageal wall that results in failure of relaxation of the lower esophageal sphincter. Differentials for secondary achalasia include multiple sclerosis, cancer of the lower esophagus or gastric fundus, and infection with the parasite trypanosoma cruzi (Chagas disease).


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