70. Thyroglossal cyst and Fistula: Cysts and fistulae found along the midline of the neck usually develop from remnants of thyroglossal duct. Generally, thyroglossal cysts maybe found at any point along the course of the thyroglossal duct but it is usually found at the level of the hyoid bone and the thyroid cartilage. Mandibulofacial Dysostosis or Treacher Collins Syndrome: This results from failure or incomplete migration of the neural crest cells to the facial region. The zygomatic bone is severely hypoplastic . The face appears to be drooping, and the ears are usually malformed. The lower border of the mandible appears concave, and cleft palate is occasionally seen.