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Head and neck surgery
Published in Mark Davenport, James D. Geiger, Nigel J. Hall, Steven S. Rothenberg, Operative Pediatric Surgery, 2020
The thyroid gland develops as a median thickening of the floor of the pharynx at the level of the second branchial arch (tuberculum impar), during the fourth week of gestation. It descends to its final position in the neck, leaving the thyroglossal duct extending caudally from the foramen cecum of the tongue to the pyramidal lobe of the thyroid, passing anteriorly through or posterior to the hyoid bone. Early in the fifth week of gestation, the attenuated duct loses its lumen and shortly afterwards breaks into fragments. Thyroid remnants may be found along the course of the thyroglossal duct.
Congenital neck lumps
Published in Neeraj Sethi, R. James A. England, Neil de Zoysa, Head, Neck and Thyroid Surgery, 2020
The diagnosis of a thyroglossal duct cyst is usually made clinically; however, imaging is essential to ensure thyroid tissue is present in the normal location. Ultrasonography is commonly used and non-invasive (see Figure 4.2). Radionucleotide thyroid imaging was previously routinely advocated and may assist in cases of diagnostic uncertainty.
Surgical Anatomy of the Thyroid
Published in Madan Laxman Kapre, Thyroid Surgery, 2020
Ashutosh Mangalgiri, Deven Mahore
An endodermal diverticulum descends in the form of primordium of the thyroid gland. The thyroid diverticulum descends as the thyroglossal duct from the foramen cecum of the tongue. The thyroglossal duct follows a particular pathway during its descent. First, it passes through the tongue, then descends anterior to the hyoid, winding round the inferior border of the hyoid, until it reaches behind the hyoid. Finally, it descends in the neck. In the neck, the thyroglossal duct forms a bi-lobed structure, which finally attains a definitive shape of the thyroid gland. The fifth pharyngeal arch contributes as ultimobranchial body. C-cells of the thyroid gland are believed to be originating from neural crest cells. In the neck, the two lobes are connected by the isthmus. Many anomalous presentations have been described in the literature, like the absence of one of the lobes, the absence of the isthmus, two lobes connected from below, and the presence of a pyramidal lobe unilaterally or bilaterally. One of the rare forms is the presence of the isthmus above the cricoid cartilage [1].
Submandibular ectopic thyroid tissue and concurrent thyroid hemiagenesis
Published in Acta Oto-Laryngologica Case Reports, 2021
Marie-Louise Uhre Hansen, Thomas Vedtofte, Irene Wessel, Mikkel Kaltoft
The thyroid gland is the first endocrine organ to develop during embryogenesis and is visible from day 20 of fetal life [1]. The Thyroid gland originates from two structures; the medial anlage derives from the primitive pharynx and the lateral anlage from the neural crest. The medial anlage has its origin at the second branchial arch level and contains the thyroxine-producing follicular cells. It is uncertain whether it arises as a paired organ or a single organ that divides into the two lobes. The lateral anlage arises from the fourth pharyngeal pouch’s ventral portion and fuses with the medial anlage at the tubercle of Zuckerkandl. The lateral anlage contains the parafollicular calcitonin-producing C-cells, explaining why these are not seen in the isthmus. The gland descends along the thyroglossal duct to its destination at the second to fourth tracheal rings, where the duct dissolves [2].
Thyroglossal duct cysts in children: a 30-year survey with emphasis on clinical presentation, surgical treatment, and outcome
Published in Acta Chirurgica Belgica, 2019
Tom Danau, Guy Verfaillie, Frans Gordts, Thomas Rose, Antoine De Backer
Thyroglossal duct cysts (TGDC) are one of the most common congenital midline deformities found in the anterior neck region in children [1]. Most of the patients are diagnosed before reaching the age of ten years [2], but TGDC can be diagnosed at any age. TGDC seem to strike both sexes almost equally [3] and appear to occur in 7% of the total population [4]. A TGDC finds its origin in the embryological development of the thyroid gland. When an embryo is 3 to 4 weeks old, a midline endodermal thickening in the primitive pharynx will occur. This thickening will evolve into a diverticulum, also known as the foramen cecum linguae. On its turn, this bilobed structure will protrude into the mesenchymal structure between the first two pharyngeal pouches. An epithelial fistula connects the foramen cecum linguae with the pharynx which is called the thyroglossal duct. During caudal projection, this duct will pass anteriorly from the mesodermal structures which will form the hyoid bone and will mount itself between the hyoid bone and the thyroid membrane. Within normal embryological development, this structure should obliterate around the tenth gestational week. However, during the descent of the duct, some epithelial structures may remain within the inferior border of the hyoid bone for unknown reasons, which can later cause the formation of a TGDC [5].
The efficacy of OK-432 sclerotherapy on thyroglossal duct cyst and the influence on a subsequent surgical procedure
Published in Acta Oto-Laryngologica, 2019
Tomoyasu Tachibana, Shin Kariya, Yorihisa Orita, Takuma Makino, Takenori Haruna, Yuko Matsuyama, Yasutoshi Komatsubara, Yuto Naoi, Michihiro Nakada, Yoji Wani, Soichiro Fushimi, Machiko Hotta, Katsuya Haruna, Tami Nagatani, Yasuharu Sato, Kazunori Nishizaki
OK-432 (Picibanil® Chugai Pharmaceutical Co., Tokyo, Japan) is a lyophilized streptococcal preparation made from the Su strain of A-group Streptococcus pyogenes incubated with penicillin [1,2]. This has been initially used as an immunotherapy agent for various malignant tumors [3]. The first line of treatment for benign non-thyroid cystic neck mass including thyroglossal duct cyst (TDC) is surgery [2]. Recently, OK-432 has also been applied to various otolaryngological cystic diseases, as a minimally invasive therapy [1,4]. Ohta et al. summarized the benefits of OK-432 therapy over the other surgical procedures as follows: (1) No hospitalization is required. (2) The treatment is painless and the time required for the procedure is brief. (3) No local anesthesia is required during the procedure. (4) Nerve injury and cosmetic problems are avoided. (5) Secondary infection and hemorrhage are rare. (6) Recurrences are less frequent [1,4].