Pyriform fistula is a relatively common congenital disorder of the neck in children. Its formation is mainly due to incomplete degeneration of the 3rd or 4th gill organ during embryonic development. It manifests as a cyst, sinus tract or fistula. Often we also refer to this as a third gill fistula or cyst. There are three types of gill slit fistulas according to what is seen clinically: 1. those with openings at both intra- and extra-pharyngeal ends are called fistulas; 2. those with openings at only one end are called incomplete fistulas (or sinus tracts); and 3. if there are no openings at either end, there are only epithelial lacunae left in the tissue, which are called cysts because of the secretions stored in them. The three lesions can be interchangeable. The external opening of the pyriform fistula is usually located in the lower anterior part of the anterior border of the sternocleidomastoid muscle, and travels up the carotid sheath via the deep surface of the broad carotid muscle, along the vagus nerve, over the hypoglossal nerve, under the glossopharyngeal nerve or stem pharyngeal muscle, bypassing the internal carotid artery and crossing the thyroglossal membrane between the hyoid bone and the superior laryngeal nerve, with the internal opening in the pyriform fossa. The disease occurs in children in equal proportions of both sexes and is mostly located on the left side. The disease is often acute and presents with painful redness and swelling of one side of the neck (often located in the anterior cervical triangle), occasionally with diffuse enlargement of the neck, and may be accompanied by enlargement of the cervical lymph nodes. Occasionally, vocal cord paralysis and regional sympathetic nerve damage may occur due to inflammation of the local laryngeal nerve. The inflammation progresses to form a local abscess, which is relieved by self-rupture or incision and drainage. The infection can also form a retropharyngeal abscess, which may even extend to the mediastinum, causing a mediastinal abscess and an abscess thorax. In the neonatal period, it may manifest as a progressively enlarging mass in the neck, with or without respiratory distress. It is prone to recurrent infections, recurrence due to improper diagnosis and treatment, and scar adhesions due to secondary or multiple surgeries, which makes surgery more difficult and more difficult to cure, causing pain to the patient and may lead to anxiety and other psychological discomfort. Clinically, the possibility of pear-shaped fistula should be considered when there is an inflammatory mass on the left side of the neck, especially if it is recurrent, repeatedly ruptured by itself or drained by incision, and when the pus culture shows streptococci or diplococci. Ultrasound or CT is useful in the diagnosis of pear fistula but the positive rate is not high. Endoscopic finding of the pyriform fossa opening is the primary method of diagnosing this disease. However, preoperative fiberoptic or electron microscopy usually does not reveal the fistula in many cases. Treatment is divided into 2 main areas: 1. Acute infection phase: anti-infective treatment should be given with broad-spectrum antibiotics including inhibition of anaerobic bacteria or sensitive antibiotics based on bacterial culture results. When an abscess is formed, some cases can break down naturally or should be promptly incised and drained, and the symptoms can mostly be relieved after the abscess subsides. After the infection subsides, complete fistula removal is usually possible after 2 weeks to avoid reinfection. Surgical removal of the fistula: Complete removal of the fistula is the key to avoid recurrence. In many cases, it is not easy to find the fistula because it is deep, small, and variable in its course, and most of them are recurrent or repeatedly infected and drained. How to find the fistula accurately and remove it completely is the key to ensure no recurrence.