text: Achalasia is caused by insufficient lower esophageal sphincter (LES) relaxation causing obstruction at gastro-esophageal junction.  It leads to absent peristalsis and stasis of food in esophagus.   To perform an X ray with barium swallow, the patient swallows a barium solution, which fails to pass smoothly through the lower esophageal sphincter. An air-fluid margin is seen over the barium column due to the lack of peristalsis. Narrowing is observed at the level of the gastroesophageal junction ("bird's beak" or "rat tail" appearance of the lower esophagus). Esophageal dilation is present in varying degrees as the esophagus is gradually stretched by retained food. A five-minute timed barium swallow is useful to measure the effectiveness of treatment.
option_0: Achalasia x ray
option_1: Achalasia CT
option_2: Achalasia MRI
option_3: Zenker's diverticulum x ray
option_4: Achalasia physical examination
option_5: Achalasia ultrasound
option_6: Barrett's esophagus physical examination
option_7: Diffuse esophageal spasm CT scan