<正> Objective: To assess the clinical value of trans-abdominal ultrasonography for the diagnosis of achalasia. Methods: The subjects were divided into 3 groups

with 8 patients suffering from achalasia as the patient group

10 normal individuals and 8 patients with cardiac carcinoma as controls. Real-time trans-abdominal ultrasonography （TAUS） was employed to investigate the lower esophagus and cardia of all subjects through water provocative test

and the sonographic findings were compared. After treated by administration of drugs

pneumatic balloon dilation or intrasphincteric injection of botulinum toxin

the 8 patients with achalasia were re-examined by TAUS for longitudinal comparison. Results: （1） The normal subjects had no dilation of cardia and lower esophagus before drinking water

but their cardias opened rapidly in accordance with the drinking action to allow water enter the stomach. （2） All the patients with achalasia were found to have dilation of lower esophagus before taking water. During a 1