title: Endoscopic ultrasonography in achalasia.
authors.affiliation: Harvard Medical School, Boston, Massachusetts.
authors.forename: J
authors.initials: J
authors.lastname: Van Dam
mesh_terms: D003937:Diagnosis, Differential; D004931:Esophageal Achalasia / Q000000981:diagnostic imaging* / Q000473:pathology*; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D004945:Esophagoscopy; D006801:Humans; D018084:Ultrasonography, Interventional