title: In the diagnosis of achalasia, "classic" might be "atypical".
authors.forename: Donald O
authors.initials: DO
authors.lastname: Castell
mesh_terms: D003937:Diagnosis, Differential; D004931:Esophageal Achalasia / Q000175:diagnosis* / Q000473:pathology*; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000473:pathology; D006801:Humans; D008365:Manometry / Q000379:methods