Ans. is 'a' i.e. Barium swallow H/O of dysphagia with more to liquids than solids suggests achalasia cardia. In all other obstructive causes of esophagus, dysphagia for solids is seen firstDiagnosis of Esophageal diseaseAny esophageal disease is first diagnosed by radiographic evaluation.Schwartz says that "The first diagnostic test in patients with suspected esophageal disease should be a barium swallow including full assessment of the stomach and duodenum"Diagnostic modalities for esophagusDiagnostic procedures to detect structural abnormalities of esophagus: -Radiographic evaluation EndoscopyTests to detect functional anomalies: -Stationary manometry 24 hour ambulatory manometry Video and cineradiography Esophageal transit scintigraphyTests to detect increased exposure to Gastric juice - 24hr. ambulatory pH monitoring- 24hr. ambulatory bile monitoring - Standard acid reflux test.Imp. Radiological findings of OesophagusBirds beak appearance*- Achalasia cardiaCork screw esophagus- Diffuse esophageal spasmCurling esophagus*- Diffuse esophageal spasmRat tailed appearance*- Achalasia cardia