cardiac sphincter

1. A ring of muscle, the cardiac sphincter, surrounds the esophagus at this point.
   此处有一肌肉环即贲门括约肌围绕着食道。
2. Bjective: Observation of the artery trend on the inferior thoracic and abdominal segment of the esophagus, especially for the cardiac sphincter region.
   目的：观察成人食管下胸段及腹段血管走向。重点观察食管下括约肌（LES）区血管走向及与下胸段血管吻合关系。

noun

1. the valve between the distal end of the esophagus and the stomach