**1. Introduction**

Esophagus is a muscular tube-like organ that originates from endodermal primitive gut, 25–28 cm long, approximately 2 cm in diameter, located between lower border of laryngeal part of pharynx (**Figure 1**) and cardia of stomach. Start and end points of esophagus correspond to 6th cervical vertebra and 11th thoracic vertebra topographically, and the gastroesophageal junction corresponds to xiphoid process of sternum. Five cm of esophagus is in the neck, and it descends over superior mediastinum and posterior mediastinum approximately 17–18 cm, continues for 1–1.5 cm in diaphragm, ending with 2–3 cm of esophagus in abdomen (**Figure 2**) [1, 2]. Sex, age, physical condition, and gender affect the length of esophagus. A newborn's esophagus is 18 cm long, and it begins and ends one or two vertebra higher than in adult. Esophagus lengthens to 22 cm long by age 3 years and to 27 cm by age 10 years [3, 4].
