Palatogenesis is a complex and intricate process involving the formation of the palate through various morphogenetic events highly dependent on the surrounding context. These events comprise outgrowth of palatal shelves from embryonic maxillary prominences, their elevation from a vertical to a horizontal position above the tongue, and their subsequent adhesion and fusion at the midline to separate oral and nasal cavities. Disruptions in any of these processes can result in cleft palate, a common congenital abnormality that significantly affects patient’s quality of life, despite surgical intervention. Although many genes involved in palatogenesis have been identified through studies on genetically modified mice and human genetics, the precise roles of these genes and their products in signaling networks that regulate palatogenesis remain elusive. Recent investigations have revealed that palatal shelf growth, patterning, adhesion, and fusion are intricately regulated by numerous transcription factors and signaling pathways, including Sonic hedgehog (Shh), bone morphogenetic protein (Bmp), fibroblast growth factor (Fgf), transforming growth factor beta (Tgf-β), Wnt signaling, and others. These studies have also identified a significant number of genes that are essential for palate development. Integrated information from these studies offers novel insights into gene regulatory networks and dynamic cellular processes underlying palatal shelf elevation, contact, and fusion, deepening our understanding of palatogenesis, and facilitating the development of more efficacious treatments for cleft palate.

BACKGROUND AND PURPOSE: The Zuckerkandl tubercle is located at the posteromedial border of the thyroid lobe, and it may be confused with a neoplasm or other mass. This study was performed to clarify the position and morphologic characteristics of the Zuckerkandl tubercle by dissecting cadavers and to compare the findings with the corresponding CT images obtained in the same cadavers. MATERIALS AND METHODS: One hundred thyroid lobes from 50 fresh cadavers were dissected for this study (20 males and 30 females; mean age at death, 77.3 ± 11.5 years). CT scans were obtained in 10 of the cadavers by using a 128-channel multidetector row CT scanner before dissection. RESULTS: The Zuckerkandl tubercle of the thyroid gland was observed in 83% of the specimens. It was mostly located at the posteromedial border of the thyroid lobe and within the middle two quarters (2nd and 3rd) of the thyroid lobe. The Zuckerkandl tubercle was classified into 3 types based on its direction of extension: posteromedial in 64% of the specimens, posteromedial and superior in 13%, and posteromedial and inferior in 6%. On axial CT, the Zuckerkandl tubercle was usually continuous with the posteromedial part of the thyroid lobe and extended posteromedially to the esophagus. The parts of the Zuckerkandl tubercle that protrude posteromedially and superiorly or posteromedially and inferiorly from the thyroid lobe appeared separated from the thyroid gland by a thin, low-density string on axial CT. CONCLUSIONS: Zuckerkandl tubercles that protrude toward the posteromedial and superior or inferior direction could cause confusion due to their separation when performing diagnoses with CT images.